JP6041087B2 - Display panel manufacturing method, inspection apparatus and inspection method thereof - Google Patents

Description

  The present invention relates to a display panel manufacturing method, an inspection apparatus and an inspection method thereof, and more particularly to a method of manufacturing a display panel having a repairable organic EL element, an inspection apparatus and an inspection method thereof.

  In recent years, display panels using organic electroluminescence elements (hereinafter referred to as organic EL elements) (hereinafter referred to as organic EL display panels) have been researched and developed as display panels capable of obtaining clear images with low power consumption. Is underway.

  The organic EL display panel constitutes a display panel by arranging a plurality of organic EL elements in a matrix. In this organic EL element, an organic electronic material is sandwiched between a pair of electrodes. Specifically, electroluminescence (injected by injecting holes and electrons into a light emitting layer made of an organic electronic material) The display is performed by utilizing a light emission phenomenon. However, it is considered difficult to form the light emitting layers of all the organic EL elements in the display panel in the shape (or pattern) as designed. For example, as the display panel has a larger area and higher definition, the organic EL element structure becomes finer and thinner, and the number of light-emitting pixels increases. An electrical failure such as a short circuit or opening of the EL element occurs.

  Therefore, in the process of manufacturing the organic EL element, a means for performing a defect inspection of the light emitting layer pattern on the substrate after forming the light emitting layer on the substrate has been studied.

  Patent Document 1 discloses an optical inspection device that detects pixel defects and protrusion defects of a color filter used in a color liquid crystal display. Specifically, light emitted from a visible light source and a short wavelength light source is converted into transmitted light and reflected light using a prism, respectively, and an optical image obtained by irradiation of the transmitted light and reflected light is used as a pixel of a color filter. Detect defects and protrusion defects.

  Patent Document 2 discloses a defect inspection method for determining a color defect of a color liquid crystal panel. Specifically, a color defect is determined from three monochrome images on a black display screen obtained by irradiating three primary colors of red, green, and blue as backlights of the color liquid crystal panel.

JP-A-10-132704 JP 2007-192613 A

  The organic EL display panel expresses a desired image by arranging organic EL elements that emit light in red, green, and blue in red light emitting pixels, green light emitting pixels, and blue light emitting pixels, respectively. In order to increase the color accuracy of each light emitting pixel, a color filter is arranged for each light emitting pixel. For example, a red color filter having a characteristic of passing only a wavelength corresponding to red in visible light is disposed on the red light emitting pixel.

  However, in the pixel defect and protrusion defect detection method using the optical inspection apparatus described in Patent Document 1, the intensity of reflected light due to short wavelength irradiation may not be sufficiently obtained depending on the passage characteristics other than visible light of the color filter. is there.

  In addition, in the defect inspection method described in Patent Document 2, in order to avoid the backlight light from being attenuated as much as possible by the pass characteristic of the color filter arranged in each pixel, the wavelength having the maximum transmittance in the pass characteristic is set. A light emitting element that emits light with a central wavelength is used as a light source of backlight. For this reason, in determining the color defect of each pixel, the detection capability of minute foreign matter may be insufficient. In particular, the resolution of red pixels tends to decrease due to the characteristics of long wavelengths.

  The present invention has been made in view of the above problems, and a display panel inspection method with high detection accuracy of defective portions of light-emitting pixels having a color filter, a display panel manufacturing method including the inspection method, and an inspection thereof An object of the present invention is to provide an inspection apparatus for realizing the method.

  A display panel inspection method according to an aspect of the present invention includes a display panel having a color filter including a plurality of display pixels having different display colors and including a display color filter arranged corresponding to the display color of the display pixels. A wavelength of the inspection method, which is shorter than a wavelength indicating the maximum transmittance in the visible light wavelength region of any one of the display color filters and having a predetermined transmittance in the visible light wavelength region. Irradiating the plurality of display pixels with the first irradiation light having a peak intensity in the step of acquiring a first optical image of the plurality of display pixels at the time of the irradiation, and And a defect detection step of detecting a defect portion of a display pixel in which the display color filter is arranged from a first optical image.

  The display panel inspection method according to one embodiment of the present invention includes a red display pixel, a green display pixel, and a blue display pixel, and includes a red filter, a green filter, and a blue filter that are disposed corresponding to each color display pixel. A method for inspecting a display panel having a color filter, wherein each visible color pixel is passed through the color filter and has a wavelength shorter than a wavelength indicating a maximum transmittance in a visible light wavelength range of the red filter, and the visible light A red short wavelength acquisition step of irradiating a second irradiation light having a peak intensity at a second wavelength exhibiting a predetermined transmittance within a wavelength range, and obtaining a second optical image of each color display pixel at the time of the irradiation, and the color filter A wavelength shorter than the wavelength indicating the maximum transmittance in the visible light wavelength region of the green filter, and the visible light wavelength region Irradiating with a third irradiation light having a peak intensity at a third wavelength exhibiting the predetermined transmittance, and obtaining a third optical image of each of the color display pixels at the time of the irradiation, and the color filter In each of the color display pixels, the peak intensity at the fourth wavelength which is shorter than the wavelength indicating the maximum transmittance in the visible light wavelength region of the blue filter and exhibits the predetermined transmittance in the visible light wavelength region. From the blue short wavelength acquisition step of obtaining a fourth optical image of each color display pixel at the time of the irradiation, the second optical image, the third optical image, and the fourth optical image. A defect detection step of detecting a defect of each color display pixel.

  According to the above configuration, the display pixel in which the color filter is arranged is irradiated with irradiation light having a peak intensity at a wavelength that is shorter than the wavelength indicating the maximum transmittance in the visible light wavelength region and has a predetermined transmittance. Thus, since an optical image of each display pixel is obtained, the detection resolution of the defect portion is improved as compared with the case of irradiating irradiation light having a peak having a wavelength indicating the maximum transmittance in the visible light wavelength region. Therefore, it is possible to detect a minute defect portion with high accuracy.

It is a functional block diagram which shows the structure of the test | inspection and repair of the organic electroluminescence display panel which concerns on embodiment of this invention. It is a circuit block diagram of the normal light emission pixel which an organic electroluminescent display panel has. It is a circuit block diagram of the defective pixel which an organic electroluminescent display panel has. 1 is a schematic cross-sectional view of a display panel according to an embodiment of the present invention. 1 is a schematic cross-sectional view of a light emitting pixel mixed with foreign matter according to an embodiment of the present invention. It is a process flowchart explaining the manufacturing method of the display panel which concerns on embodiment of this invention. It is an operation | movement flowchart explaining the 1st test | inspection method of the display panel which concerns on embodiment of this invention. It is an operation | movement flowchart explaining the 2nd test | inspection method of the display panel which concerns on embodiment of this invention. It is a 1st graph showing the relationship between the wavelength of the irradiation light used with the inspection method which concerns on embodiment of this invention, and the passage characteristic of a color filter. It is a 2nd graph showing the relationship between the wavelength of the irradiation light used with the inspection method which concerns on embodiment of this invention, and the passage characteristic of a color filter. It is a figure showing the optical image acquired by the inspection method of the display panel which concerns on embodiment of this invention. It is a figure showing the optical image at the time of irradiating visible light to a light emission pixel. It is a figure showing the optical image at the time of irradiating a light emitting pixel with infrared light. It is a figure showing the lighting confirmation after laser repair. It is the cross-sectional schematic of the light emitting pixel which concerns on the 1st modification of embodiment of this invention. It is the cross-sectional schematic of the light emitting pixel which concerns on the 2nd modification of embodiment of this invention. It is an external view of the television system provided with the light emission panel by the manufacturing method of this invention.

  A display panel manufacturing method, an inspection apparatus and an inspection method thereof according to an embodiment of the present invention will be described. Each of the embodiments described below shows a preferred specific example of the present invention. The numerical values, shapes, materials, constituent elements, arrangement positions and connecting forms of the constituent elements, steps, order of steps, and the like shown in the following embodiments are merely examples, and are not intended to limit the present invention. The invention is specified by the claims. Therefore, among the constituent elements in the following embodiments, constituent elements that are not described in the independent claims indicating the highest concept of the present invention are not necessarily required to achieve the object of the present invention. It will be described as constituting a preferred form.

  A display panel inspection method according to an aspect of the present invention includes a display panel having a color filter including a plurality of display pixels having different display colors and including a display color filter arranged corresponding to the display color of the display pixels. A wavelength of the inspection method, which is shorter than a wavelength indicating the maximum transmittance in the visible light wavelength region of any one of the display color filters and having a predetermined transmittance in the visible light wavelength region. Irradiating the plurality of display pixels with the first irradiation light having a peak intensity in the step of acquiring a first optical image of the plurality of display pixels at the time of the irradiation, and And a defect detection step of detecting a defect portion of a display pixel in which the display color filter is arranged from a first optical image.

  According to this aspect, the first irradiation light having a peak intensity at a wavelength shorter than the wavelength indicating the maximum transmittance in the visible light wavelength region of the display color filter and having a predetermined transmittance in the visible light wavelength region. The display pixel is irradiated through the color filter. Thereby, the detection resolution of the defect part which the display pixel in which the said display color filter is arrange | positioned improves compared with the case where the irradiation light which has the wavelength which shows the maximum transmittance | permeability in a visible light wavelength range is peaked. Therefore, it is possible to detect a minute defect portion with high accuracy.

  Further, there are a plurality of wavelengths that are shorter than the wavelength indicating the maximum transmittance in the visible light wavelength region of any one of the display color filters and exhibit a predetermined transmittance in the visible light wavelength region. In the short wavelength acquisition step, the display pixel may be irradiated with the first irradiation light having the peak intensity at the shortest wavelength among the plurality of wavelengths.

  Depending on the pass characteristics of the display color filter, there may be a sub-pass band on the short wavelength side in the visible light region. At this time, there may be a plurality of wavelengths exhibiting a predetermined transmittance in the visible light wavelength range depending on the set value of the predetermined transmittance. In this case, the display pixel is irradiated with the irradiation light having the peak intensity at the shortest wavelength among the plurality of wavelengths as the first irradiation light. Thereby, compared with the case of irradiating irradiation light having a peak intensity at a wavelength exhibiting a predetermined transmittance in the main pass band, it is possible to irradiate light having a shorter wavelength, and thus the detection resolution of the defect portion is further improved.

  A display panel inspection method according to an aspect of the present invention includes a red display pixel, a green display pixel, and a blue display pixel, and a color filter including a red filter, a green filter, and a blue filter arranged corresponding to each color display pixel. A display panel having a wavelength shorter than a wavelength indicating a maximum transmittance in the visible light wavelength region of the red filter through the color filter and within the visible light wavelength region. The second short-wavelength acquisition step of irradiating the second irradiation light having the peak intensity at the second wavelength exhibiting a predetermined transmittance and obtaining the second optical image of each color display pixel at the time of the irradiation, and through the color filter In each of the color display pixels, the green filter has a wavelength shorter than the wavelength indicating the maximum transmittance in the visible light wavelength region, A green short wavelength acquisition step of irradiating a third irradiation light having a peak intensity at a third wavelength exhibiting a predetermined transmittance and obtaining a third optical image of each color display pixel at the time of the irradiation, through the color filter Each color display pixel has a peak intensity at a fourth wavelength which is shorter than the wavelength indicating the maximum transmittance in the visible light wavelength region of the blue filter and exhibits the predetermined transmittance in the visible light wavelength region. A blue short wavelength acquisition step of irradiating a fourth irradiation light to obtain a fourth optical image of each color display pixel at the time of the irradiation, and each color from the second optical image, the third optical image, and the fourth optical image And a defect detection step of detecting a defect of the display pixel.

  According to this aspect, each of the red filter, the green filter, and the blue filter has a peak at a wavelength that is shorter than the wavelength that exhibits the maximum transmittance in the visible light wavelength region and that exhibits the predetermined transmittance in the visible light wavelength region. By irradiating each color display pixel with irradiation light having intensity through a color filter, it becomes possible to inspect defective portions of all display pixels. In addition, the detection resolution of the defect portion is improved as compared with the case of irradiating irradiation light having a peak with a wavelength indicating the maximum transmittance in the visible light wavelength region. Therefore, it is possible to detect a minute defect portion with high accuracy over the entire display panel.

  In the red short wavelength acquisition step, when there are a plurality of the second wavelengths, the display pixel is irradiated with the second irradiation light having a peak intensity at the shortest wavelength among the plurality of the second wavelengths. In the green short wavelength acquisition step, when there are a plurality of the third wavelengths, the display pixel is irradiated with the third irradiation light having a peak intensity at the shortest wavelength among the plurality of the third wavelengths, In the blue short wavelength acquisition step, when there are a plurality of the fourth wavelengths, the display pixel may be irradiated with the fourth irradiation light having a peak intensity at the shortest wavelength among the plurality of the fourth wavelengths. Good.

  Thereby, compared with the case of irradiating irradiation light having a peak intensity at a wavelength exhibiting a predetermined transmittance in the main pass band, it is possible to irradiate light having a shorter wavelength, and thus the detection resolution of the defect portion is further improved.

  In the defect detection step, a defect of each color display pixel may be detected from an image synthesized by arbitrarily adjusting the exposure amounts of the second optical image, the third optical image, and the fourth optical image. Good.

  There may be a difference in brightness, contrast, and the like of the second optical image, the third optical image, and the fourth optical image depending on the set predetermined transmittance. In this case, by adjusting the exposure amount of each optical image arbitrarily, it is possible to detect a defective portion with high accuracy without deviation between display pixels.

  Each of the color display pixels may include an organic electroluminescence light emitting layer sandwiched between a cathode and an anode, and the defect detection step may detect the defect portion in which the cathode and the anode are short-circuited.

  According to this aspect, it is possible to detect a short-circuit defect portion occurring in the organic EL light emitting layer sandwiched between the anode and the cathode with high accuracy.

  Further, in the defect detection step, an area where the luminance value measured by the first optical image is a predetermined value or more may be determined as the defect portion.

  Further, in the defect detection step, an area where a luminance value measured by the second optical image, the third optical image, and the fourth optical image is a predetermined value or more may be determined as the defect portion. .

  A display pixel having a defective portion due to short circuit or opening causes the defective portion to have higher brightness than the normal portion due to the reflected light or scattered light due to the irradiation of the first to fourth irradiation lights. Therefore, it is possible to detect a defect with high accuracy by determining a region having a luminance value greater than or equal to a predetermined value as a defective portion from the acquired optical image.

  Note that the present invention can be realized not only as such a display panel inspection method but also as a display panel inspection apparatus that implements the characteristic steps included in the inspection method.

  Further, the present invention can be realized not only as a display panel inspection method, but also as a display panel manufacturing method using characteristic steps included in the inspection method.

  A method for manufacturing a display panel according to one aspect of the present invention includes a display panel having a color filter including a plurality of display pixels having different display colors and including a display color filter arranged corresponding to the display color of the display pixels. A display pixel forming step of forming the display pixels in a matrix on a display panel substrate and forming the color filter on the display pixels; and any one of the display color filters A first irradiation light having a peak intensity at a wavelength shorter than a wavelength indicating the maximum transmittance in the visible light wavelength region of the display color filter and exhibiting a predetermined transmittance in the visible light wavelength region; A short wavelength acquisition step of irradiating the plurality of display pixels via the first optical image and acquiring a first optical image of the plurality of display pixels at the time of the irradiation, A defect detection step of detecting a defective portion of the display pixel 示色 filter is arranged, the defect for which is detected by the defect detection step, characterized in that it comprises a repair step of performing a repair.

  In addition, a method for manufacturing a display panel according to one embodiment of the present invention includes a red display pixel, a green display pixel, and a blue display pixel, and includes a red filter, a green filter, and a blue filter that are arranged corresponding to each color display pixel. A method of manufacturing a display panel having a color filter, wherein the red display pixel, the green display pixel, and the blue display pixel are formed in a matrix on a display panel substrate, and the color display pixel is formed on each color display pixel. A display pixel forming step of forming a filter, and each color display pixel via the color filter has a wavelength shorter than the wavelength indicating the maximum transmittance in the visible light wavelength region of the red filter and within the visible light wavelength region. A second irradiation image having a peak intensity at a second wavelength exhibiting a predetermined transmittance is irradiated, and a second optical image of each color display pixel at the time of the irradiation. And obtaining each of the color display pixels via the color filter with a wavelength shorter than the wavelength indicating the maximum transmittance in the visible light wavelength region of the green filter and the predetermined wavelength within the visible light wavelength region. A green short wavelength acquisition step of irradiating a third irradiation light having a peak intensity at a third wavelength indicating the transmittance of the light to obtain a third optical image of each color display pixel at the time of the irradiation, and through the color filter Each color display pixel has a peak intensity at a fourth wavelength which is shorter than the wavelength indicating the maximum transmittance in the visible light wavelength region of the blue filter and has the predetermined transmittance within the visible light wavelength region. A blue short wavelength acquisition step of irradiating four irradiation lights and obtaining a fourth optical image of each color display pixel at the time of the irradiation, the second optical image, the third optical image, and the fourth optical image; A defect detecting step of detecting al the defect of each color display pixel, for the defective portion detected by said defect detecting step, characterized in that it comprises a repair step of performing a repair.

  According to these manufacturing methods, it is possible to detect a minute defect portion of a light emitting pixel with high accuracy by irradiating irradiation light having a peak intensity at a wavelength shorter than the wavelength exhibiting the maximum transmittance in the visible light wavelength region of the color filter. It becomes possible. This highly accurate detection of a defective portion can surely carry out repair of the defective portion, so that the manufacturing yield is improved.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. In the following description, the same or corresponding elements are denoted by the same reference numerals throughout all the drawings, and redundant description thereof is omitted.

(Embodiment)
A display panel inspection apparatus, inspection method, and manufacturing method according to an embodiment of the present invention will be described.

<System configuration>
FIG. 1 is a functional block diagram showing a configuration of inspection and repair of an organic EL display panel according to an embodiment of the present invention. The configuration of inspection and repair of the organic EL display panel shown in FIG. 1 includes an inspection device 1, a display device 2, and a repair device 3. It is to be noted that the display panel 22 is a target for carrying out the inspection method and the manufacturing method of the present invention, and the control unit 21, the data line driving circuit 23, and the scanning line driving circuit 24 included in the display device 2 are not constituent elements. May be.

  First, the display device 2 will be briefly described. The display device 2 includes a control unit 21, a display panel 22, a data line driving circuit 23, and a scanning line driving circuit 24.

  The control unit 21 converts a video signal input from the outside into a luminance signal that determines light emission of the light emitting pixels, and outputs the luminance signal to the data line driving circuit 23 in the scanning order. Further, the control unit 21 controls the timing of outputting the luminance signal output from the data line driving circuit 23 and the output timing of the scanning signal output from the scanning line driving circuit 24.

  The data line driving circuit 23 realizes light emission of the light emitting pixels corresponding to the video signal by outputting a luminance signal to each data line.

  The scanning line driving circuit 24 drives a circuit element included in the light emitting pixel at a predetermined driving timing by outputting a scanning signal to each scanning line.

  Note that the control unit 21, the data line driving circuit 23, and the scanning line driving circuit 24 may be used when supplying repaired lighting inspection data to the display panel 22 in the manufacturing method of the present invention.

  The display panel 22 has a plurality of light emitting pixels arranged in a matrix. Each of the plurality of light emitting pixels is any one of a red display pixel that displays red, a green display pixel that displays green, and a blue display pixel that displays blue. Each color display pixel includes a display color filter corresponding to each color. Is formed. Each of the plurality of light emitting pixels emits light according to the luminance signal from the data line driving circuit 23 and the scanning signal from the scanning line driving circuit 24.

  FIG. 2A is a circuit configuration diagram of a normal light emitting pixel included in the organic EL display panel. The light emitting pixel shown in the figure includes an organic EL element 221, a drive transistor 222, a selection transistor 223, and a capacitor 224. In addition, a data line 231 is disposed for each light emitting pixel column, a scanning line 241 is disposed for each light emitting pixel row, and a positive power supply line 251 and a negative power supply line 261 are disposed in common to all the light emitting pixels. The drain electrode of the selection transistor 223 is connected to the data line 231, the gate electrode of the selection transistor 223 is connected to the scanning line 241, and the source electrode of the selection transistor 223 is connected to the capacitor 224 and the gate electrode of the driving transistor 222. The drain electrode of the driving transistor 222 is connected to the positive power supply line 251, and the source electrode is connected to the anode of the organic EL element 221.

  The organic EL element 221 has a structure in which, for example, an anode, a hole injection layer, an organic light emitting layer, an electron injection layer, and a cathode are laminated in this order, holes from the anode side, electrons from the cathode side, By being injected into the organic light emitting layer and recombined, an excited state is generated and has a function of emitting light. As the organic light emitting layer, not only a low molecular weight organic material but also a light emitting polymer organic material that can be formed by a wet film forming method such as ink jet or spin coating is applied.

  In this configuration, when a scanning signal is input to the scanning line 241 and the selection transistor 223 is turned on, a luminance signal corresponding to the light emission gradation supplied through the data line 231 is written into the capacitor 224. Then, the holding voltage written in the capacitor 224 is held throughout one frame period, and the holding voltage changes the conductance of the driving transistor 222 in an analog manner, so that the driving current corresponding to the light emission gradation is applied to the organic EL element 221. Supplied to the anode. Further, the drive current supplied to the anode of the organic EL element 221 flows to the cathode of the organic EL element 221. Thereby, the organic EL element 221 emits light and is displayed as an image. At this time, a forward bias voltage is applied to the anode of the organic EL element 221.

  Note that the circuit configuration of the light emitting pixel described above is not limited to the circuit configuration illustrated in FIG. 2A. The selection transistor 223 and the drive transistor 222 are circuit components necessary for flowing a drive current corresponding to the voltage value of the luminance signal to the organic EL element 221, but are not limited to the above-described form. Further, a case where another circuit component is added to the above-described circuit components is also included in the light emitting pixel circuit of the display device according to the present invention.

  In an active matrix organic EL display panel, as the structure of a light emitting pixel is miniaturized and thinned, and as the number of light emitting pixels is increased, an anode of an organic EL element is used in a manufacturing process that requires fine processing. Electrical problems such as short-circuiting and opening between the cathodes occur.

  FIG. 2B is a circuit configuration diagram of a defective pixel included in the organic EL display panel. The circuit configuration shown in the figure represents a state where the anode and cathode of the organic EL element are short-circuited. That is, as compared with the circuit configuration shown in FIG. 2A, a difference is that a short-circuit component 422 that realizes an electrical conduction state is connected in parallel between the anode and the cathode of the organic EL element 421. Here, the state in which the organic EL element 421 is short-circuited is defined as the organic EL element 421 being in a short-circuited state when the resistance value of the short-circuit component 422 is in a low-resistance state. As an example of the case where the anode and cathode of the organic EL element 421 are short-circuited, due to the nonuniformity of the thickness of the organic light emitting layer, the hole injection layer and the electron transport layer sandwiching the organic light emitting layer are organic light emitting layers. The case where it is in point contact through the pinhole produced inside is assumed.

  When the light emitting pixel described in FIG. 2B in which the organic EL element is short-circuited is present in the display panel 22, the short-circuit component 422 is removed by a repair process in the manufacturing stage of the organic EL display panel. Is possible. As a repair process for removing the short-circuit component 422, for example, irradiating a portion where the short-circuit component 422 is present with a laser can be mentioned. This repair process will be described in a method for manufacturing an organic EL display panel described later.

  Next, the configuration and function of the inspection apparatus 1 according to the embodiment of the present invention will be described. The inspection apparatus 1 illustrated in FIG. 1 includes an irradiation unit 11, a luminance measurement unit 12, and a determination unit 13. The inspection device 1 has a function of specifying a defective pixel of the display device 2 before the repair work by the repair device 3.

  The irradiation unit 11 has a peak intensity at a wavelength shorter than a wavelength indicating the maximum transmittance in the visible light wavelength region of any one of the display color filters and exhibiting a predetermined transmittance in the visible light wavelength region. It has the function to irradiate each light emitting pixel with the 1st irradiation light which has. The irradiation unit 11 indicates the maximum transmittance in the visible light wavelength range of the red color filter disposed in the red light emitting pixel, the green color filter disposed in the green light emitting pixel, and the blue color filter disposed in the blue light emitting pixel. Each of the light emitting pixels has a function of irradiating the second irradiation light, the third irradiation light, and the fourth irradiation light having a peak intensity at a wavelength that is shorter than the wavelength and has a predetermined transmittance. The irradiation unit 11 has a function of adjusting the amount of emitted light for each irradiation light corresponding to each color filter according to the predetermined transmittance. The irradiation unit 11 includes, for example, a laser light source that emits first to fourth irradiation light. Moreover, the irradiation part 11 is provided with the LED (Light Emitting Diode) light source which radiate | emits 1st-4th irradiation light, for example.

  The luminance measuring unit 12 acquires the first to fourth optical images of the display panel 22 at the time of irradiation of the first to fourth irradiation lights, and the irradiation light corresponding to each color filter based on the optical image. Based on the image obtained by synthesizing the second to fourth optical images obtained for each, the pixel has a function of measuring the light emission luminance for each region where each light emitting pixel is subdivided. The luminance measurement unit 12 includes, for example, a CCD camera. Here, it is preferable that the luminance measurement unit 12 has a function of adjusting the exposure amount for each optical image in accordance with the predetermined transmittance and the difference in brightness and contrast for each optical image.

  The determination unit 13 has a function of determining a defective portion for each region based on the magnitude of the light emission luminance measured by the luminance measurement unit 12.

  Further, the determination unit 13 transmits the defective pixel determined to have a defective part and position information of the defective part to the repair device 3.

  The repair device 3 executes the repair work from the defective pixel obtained from the determination unit 13 and the position information of the defective part.

  According to the configuration and function of the inspection apparatus 1 for the display panel 22 described above, the irradiation unit 11 emits the irradiation light, the luminance measurement unit 12 acquires the optical image, and each light emitting pixel is captured by the optical image. Compared to the case of irradiating irradiation light having a peak intensity at a wavelength indicating the maximum transmittance in the visible light wavelength region by measuring the emission luminance for each subdivided region and determining the defect portion by the determination unit 13. Thus, the detection resolution of the defective portion is improved. Therefore, it is possible to detect a minute defect portion with high accuracy.

  Next, the structure of the light emitting pixels included in the display panel 22 will be described.

  FIG. 3A is a schematic cross-sectional view of a display panel according to an embodiment of the present invention. The display panel 22 shown in the figure is an organic functional device having an organic layer 130 including an anode, a cathode, and a light emitting layer sandwiched between the two electrodes. In the display panel 22 shown in the figure, one unit pixel formed by adjacently arranging red light emitting pixels 22R, green light emitting pixels 22G, and blue light emitting pixels 22B, which are sub-pixels, is arranged in a matrix. Yes. Each subpixel has a planarization film 111, an anode 112, a hole injection layer 113, a light emitting layer 114, a partition wall 123, an electron injection layer 115, a cathode 116, and a thin film encapsulation on a substrate 110. A layer 117, a sealing resin layer 118, a color filter 122, an adhesive layer 119, and a transparent substrate 120 are provided. In FIG. 3A, the color filter 122 corresponds to the red light emitting pixel 22R, the green light emitting pixel 22G, and the blue light emitting pixel 22B, respectively, and the red color filter 122R that preferentially transmits red in the visible light region and the visible light region, respectively. The green color filter 122G that preferentially transmits green and the blue color filter 122B that preferentially transmits blue in the visible light region are represented. A black matrix 121 is disposed between the red color filter 122R, the green color filter 122G, and the blue color filter 122B.

  The anode 112 and the cathode 116 correspond to the lower electrode layer and the upper electrode layer in the present invention, respectively. The hole injection layer 113, the light emitting layer 114, and the electron injection layer 115 correspond to the organic layers in the present invention.

  The substrate 110 and the transparent substrate 120 are substrates that protect the back surface and the light emitting surface of the display panel 22, and are, for example, transparent non-alkali glass having a thickness of 0.5 mm.

  For example, the planarization film 111 is made of an insulating organic material, and is formed on a substrate including, for example, a driving thin film transistor (TFT).

  The anode 112 is supplied with holes, that is, an anode through which an electric current flows from an external circuit, and has a structure in which a reflective electrode made of, for example, Al or silver alloy APC is laminated on the planarizing film 111. Yes. The thickness of the reflective electrode is 10 to 40 nm as an example.

  The hole injection layer 113 is a layer mainly composed of a hole injecting material. The hole injecting material is a material having a function of injecting holes injected from the anode 112 side into the light emitting layer 114 stably or by assisting generation of holes.

  The light emitting layer 114 is a layer that emits light when a voltage is applied between the anode 112 and the cathode 116. For example, α-NPD (Bis [N- (1-naphthyl) -N-phenyl] benzidine) as a lower layer, As the upper layer, Alq3 (tris- (8-hydroxyquinoline) aluminum) is laminated.

  The electron injection layer 115 is a layer mainly composed of an electron injecting material. The electron injecting material is a material having a function of injecting electrons injected from the cathode 116 into the light emitting layer 114 stably or by assisting generation of electrons.

  The cathode 116 is a cathode to which electrons are supplied, that is, a current flows out to an external circuit, and has a structure in which, for example, ITO is laminated as a transparent metal oxide. The thickness of the electrode is 10 to 40 nm as an example.

  The partition wall 123 is a wall for separating the light emitting layer 114 for each sub-pixel, and is made of, for example, a photosensitive resin.

  The thin film sealing layer 117 is made of, for example, silicon nitride and has a function of blocking the light emitting layer 114 and the cathode 116 from water vapor and oxygen. This is to prevent the light emitting layer 114 itself or the cathode 116 from being deteriorated (oxidized) by being exposed to water vapor or oxygen.

  The sealing resin layer 118 is an acrylic or epoxy resin, and joins the color filter 122 and the layer formed integrally from the planarization film 111 to the thin film sealing layer 117 formed on the substrate. Has the function of

  The color filter 122 has a red color filter 122R, which is a red filter for performing red color adjustment, and green color adjustment on the lower surface of the transparent substrate 120 and the adhesive layer 119 so as to cover each light emitting region separated by the partition wall 123. A green color filter 122G that is a green filter to be performed and a blue color filter 122B that is a blue filter that performs blue color adjustment are configured.

  The configuration of the anode 112, the light emitting layer 114, and the cathode 116 described above is a basic configuration of the organic EL element. With this configuration, when an appropriate voltage is applied between the anode 112 and the cathode 116, the anode 112 side To holes and electrons from the cathode 116 side are respectively injected into the light emitting layer 114. By the energy generated by recombination of the injected holes and electrons in the light emitting layer 114, the light emitting material of the light emitting layer 114 is excited and emits light.

  Note that the materials of the hole injection layer 113 and the electron injection layer 115 are not limited in the present invention, and a known organic material or inorganic material is used.

  Further, as a configuration of the display panel 22, a hole transport layer may be provided between the hole injection layer 113 and the light emitting layer 114, and an electron transport layer is provided between the electron injection layer 115 and the light emitting layer 114. May be. Further, a hole transport layer may be disposed instead of the hole injection layer 113, or an electron transport layer may be disposed instead of the electron injection layer 115. The hole transport layer is a layer mainly composed of a material having a hole transport property. Here, the hole transporting material has both the property of having an electron donor property and easily becoming a cation (hole) and the property of transferring the generated hole by intermolecular charge transfer reaction. It is a material having appropriateness for charge transport to the light emitting layer 114. The electron transport layer is a layer mainly composed of an electron transport material. Here, the electron transporting material has both an electron accepting property and a property of easily becoming an anion, and a property of transferring generated electrons by a charge transfer reaction between molecules, from the cathode 116 to the light emitting layer 114. A material that has suitability for charge transport.

  FIG. 3B is a schematic cross-sectional view of a luminescent pixel mixed with foreign matter according to an embodiment of the present invention. In the green light emitting pixel 22G shown in the figure, in the manufacturing process, conductive foreign matter 50 is mixed between the anode 112 and the cathode 116, and the anode 112 and the cathode 116 are short-circuited via the foreign matter 50. In the method for manufacturing a display panel according to the present invention, when the foreign substance 50 is determined to be a defective part in the determination unit 13, for example, laser irradiation is performed on the foreign substance 50 or a part of the cathode 116 around it. By increasing the resistance, the short circuit between the anode 112 and the cathode 116 short-circuited by the foreign material 50 is eliminated (repaired). The repair process for the shorted part will be described later.

<Inspection method and manufacturing method>
Next, the display panel inspection method and manufacturing method of the present invention will be described.

  FIG. 4 is a process flowchart illustrating a method for manufacturing a display panel according to an embodiment of the present invention.

  First, the display panel 22 is formed on the substrate (S10).

  Next, the light emitting pixels of the display panel 22 formed in step S10 are inspected (S20).

  Finally, the defective pixel identified in step S20 is repaired (S30).

  Hereinafter, steps S10 to S30 will be described in detail.

  First, the process for forming the display panel in step S10 will be described. Specifically, the display panel 22 shown in FIG. 3A is prepared.

  First, the planarization film 111 made of an insulating organic material is formed over the substrate 110 including the TFT, and then the anode 112 is formed over the planarization film 111. For example, the anode 112 is formed by depositing Al on the planarizing film 111 by a sputtering method to a thickness of 30 nm, and then performing a patterning process by photolithography and wet etching.

  Next, the hole injection layer 113 is formed on the anode 112 by, for example, dissolving PEDOT in a solvent made of xylene and spin-coating this PEDOT solution.

  Next, α-NPD and Alq3 are stacked on the hole injection layer 113 by, for example, a vacuum evaporation method, and the light emitting layer 114 is formed.

  Next, on the light emitting layer 114, for example, polyphenylene vinylene (PPV) is dissolved in a solvent made of xylene or chloroform and spin-coated, thereby forming the electron injection layer 115.

  Subsequently, the cathode 116 is formed without exposing the substrate on which the electron injection layer 115 is formed to the atmosphere. Specifically, the cathode 116 is formed by depositing 35 nm of ITO (Indium Tin Oxide) on the electron injection layer 115 by sputtering. At this time, the cathode 116 is in an amorphous state.

  By the manufacturing process, an organic EL element having a function as a light emitting element is formed. Note that a partition wall 123 made of a surface photosensitive resin is formed at a predetermined position between the formation process of the anode 112 and the formation process of the hole injection layer 113.

Next, 500 nm of silicon nitride is laminated on the cathode 116 by, for example, plasma CVD (Chemical Vapor Deposition) to form a thin film sealing layer 117. Since the thin film sealing layer 117 is formed in contact with the surface of the cathode 116, it is particularly preferable that the necessary condition as a protective film is made strict, and a non-oxygen-based inorganic material represented by the above-described silicon nitride is used. preferable. Further, for example, an oxygen-based inorganic material such as silicon oxide (Si _X O _Y ) or silicon oxynitride (Si _X O _Y N _Z ), or a structure in which a plurality of these inorganic materials are formed may be used. Further, the forming method is not limited to the plasma CVD method, and may be other methods such as a sputtering method using argon plasma.

  Next, a sealing resin layer 118 is applied to the surface of the thin film sealing layer 117. Thereafter, the color filter 122 is formed on the applied sealing resin layer 118.

  Next, the adhesive layer 119 and the transparent substrate 120 are disposed on the color filter 122. The thin film sealing layer 117, the sealing resin layer 118, the adhesive layer 119, and the transparent substrate 120 correspond to the protective layer in the present invention.

  Finally, the sealing resin layer 118 is cured by applying heat or energy rays while pressing the transparent substrate 120 downward from the upper surface side, and the transparent substrate 120, the adhesive layer 119, the color filter 122, and the thin film sealing layer 117. And glue.

  The display panel 22 shown in FIG. 3A is formed by the above forming method. In addition, the formation process of the anode 112, the hole injection layer 113, the light emitting layer 114, the electron injection layer 115, and the cathode 116 is not limited by this invention.

  Next, returning to the process flowchart of FIG. 4, the light emitting pixel inspection process in step S <b> 20 which is the main part of the present invention will be described. Hereinafter, the process of obtaining the process will be described before the process is specifically described.

  In the manufacturing process of the display panel 22, as shown in FIG. 2B and FIG. 3B, for example, when a foreign substance 50 or the like is mixed in the organic layer and the organic EL element has a short-circuit defect portion, a signal is sent to the organic EL element. Even when a voltage corresponding to the voltage is applied, current flows preferentially to the short-circuit defect portion. For this reason, a normal current does not flow through the organic EL element, resulting in a dark spot. Therefore, the organic EL element is required to detect a short-circuit defect portion causing the dark spot and repair the corresponding place in order to prevent the dark spot.

  Therefore, as a method for detecting the presence or absence of a defective portion in the organic EL element, the display panel 22 is irradiated with light from the transparent substrate 120 side, and reflected light or scattered light obtained through the color filter 122 is imaged with a detector. The optical image of the display panel 22 obtained by doing so may be used to determine whether or not a defective portion exists in the organic EL element.

  However, when the light source applied to the display panel 22 is visible light, the light applied to the display panel 22 passes through the color filter 122, so that the applied light is absorbed according to the transmission characteristics of the color filter 122.

  FIG. 7B is a diagram illustrating an optical image when visible light is irradiated to a light emitting pixel. The optical image shown in the figure is obtained when the red light emitting pixel 22R, the green light emitting pixel 22G, and the blue light emitting pixel 22B are irradiated with visible light through the color filter 122. As shown in FIG. 7B, when each light emitting pixel is irradiated with visible light, a defective portion is not detected particularly in the blue light emitting pixel 22B. Here, the blue light emitting pixel 22B that emits blue light is provided with a blue color filter 122B that transmits blue light. The blue color filter 122B has a characteristic of absorbing and not transmitting light according to colors other than blue in the visible light region. That is, when the blue light emitting pixel 22B is irradiated with white light (visible light), an optical image is obtained with a wavelength corresponding to blue. Here, it is generally known that the blue color filter 122B has a low blue transmittance, and the blue detection intensity (sensitivity) of a detector from which an optical image is to be acquired is low. Therefore, as shown in FIG. 7B, when visible light is irradiated to each light emitting pixel, it is difficult to obtain an optical image capable of detecting a defective portion, particularly in the blue light emitting pixel 22B.

  FIG. 7C is a diagram illustrating an optical image when infrared light is irradiated to the light emitting pixels. The optical image shown in the figure is obtained when the red light emitting pixel 22R, the green light emitting pixel 22G, and the blue light emitting pixel 22B are irradiated with infrared light through the color filter 122. As shown in FIG. 7C, when each light emitting pixel is irradiated with infrared light, if each color filter constituting the color filter 122 has a characteristic of transmitting an infrared region, a defective portion can be visually recognized in each color light emitting pixel. . However, infrared light has a longer wavelength than visible light, and the resolution of an optical image is lowered and scattered light is reduced, so that the detection rate of a minute defect portion is lowered.

  That is, as shown in FIG. 7C, in order to reduce the influence of the color filter 122, if the light source irradiated to the display panel 22 is infrared light, the detection sensitivity of the minute defect portion is lowered.

  The above-described decrease in detection accuracy of the blue light emitting pixel 22B in the visible light irradiation and the minute defect portion in the infrared light irradiation is unique when detecting the defective portion of the display panel 22 with the color filter 122 disposed, It has not been studied so far.

  As described above, through a series of studies, the present inventor applied the display panel 22 that is a substrate to be inspected to a wavelength indicating the maximum transmittance in the visible light wavelength region of any one of the red, green, and blue color filters. The detection method of irradiating irradiation light having a peak intensity at a wavelength that is shorter and has a predetermined transmittance has been achieved. In other words, using a monochromatic light source having the shortest wavelength among the wavelengths shorter than the infrared light and having a predetermined transmittance that is not the maximum transmittance of the color filter, the light emitting pixel in which the color filter is disposed is used. Detect defective parts. Thereby, the detection resolution of the defect portion is improved as compared with the case where the light emitting pixel in which the color filter is arranged is irradiated with the irradiation light having the peak intensity at the wavelength showing the maximum transmittance in the visible light wavelength region. Therefore, the detection capability of the minute defect portion is improved. In particular, in the case of a red color filter, when irradiating irradiation light whose peak wavelength is the maximum transmittance, the resolution is likely to deteriorate due to the characteristics due to the long wavelength. In addition, when the irradiation light which has peak intensity in the wavelength which shows the said predetermined transmittance | permeability is irradiated, since the said predetermined transmittance | permeability is not the maximum transmittance | permeability, attenuation | damping by a color filter is large. Therefore, it is assumed that sufficient light emission intensity cannot be obtained in the optical image. However, since the light emitting pixel that detects the defective portion by the irradiation of the irradiation light is a light emitting pixel in which a color filter having the same color as the color filter is disposed, the emitted light amount of the irradiation light and the exposure amount of the optical image are adjusted. This makes it possible to obtain sufficient light emission intensity in the optical image.

  Further, as a method for inspecting defective portions of all the light emitting pixels of the display panel 22 as well as the light emitting pixels in which the specific color filter is disposed, the red color filter is shorter than the wavelength indicating the maximum transmittance in the visible light wavelength region. Second irradiation light having a peak intensity at a wavelength with a predetermined transmittance, and third irradiation light having a peak intensity at a wavelength with a predetermined transmittance shorter than a wavelength indicating the maximum transmittance in the visible light wavelength region of the green color filter. And the 4th irradiation light which has a peak intensity in the wavelength which is shorter than the wavelength which shows the maximum transmittance | permeability in the visible light wavelength range of a blue color filter, and becomes a predetermined transmittance | permeability is each irradiated to the display panel 22. And the optical image of the red light emission pixel in the 2nd optical image acquired at the time of 2nd irradiation light irradiation, the optical image of the green light emission pixel in the 3rd optical image acquired at the time of 3rd irradiation light irradiation, and 4th irradiation light The optical image of the blue light-emitting pixel in the fourth optical image acquired at the time of irradiation can be combined with the exposure amount arbitrarily adjusted, so that even in all the light-emitting pixels, highly accurate minute defect portions can be detected. It becomes possible.

  Hereinafter, the inspection process of step 20 will be described in detail.

  FIG. 5A is an operation flowchart for explaining the first inspection method for the display panel according to the embodiment of the present invention.

  First, the irradiation unit 11 has a peak intensity at a wavelength that is shorter than a wavelength indicating the maximum transmittance in the visible light region of any one of the red, green, and blue color filters and has a predetermined transmittance. The display panel 22 is irradiated with irradiation light (S201). At this time, the irradiation unit 11 focuses the first irradiation light on the surface of the display panel 22. Here, the wavelength of the first irradiation light will be described with reference to FIG.

FIG. 6A is a first graph showing the relationship between the wavelength of irradiation light used in the inspection method according to the embodiment of the present invention and the pass characteristics of a color filter. The figure shows a first example of wavelength-transmittance characteristics for the red color filter 122R, the green color filter 122G, and the blue color filter 122B. In the red color filter 122R, the green color filter 122G, and the blue color filter 122B, the wavelengths that exhibit the maximum transmittance in the visible light region (380 nm to 800 nm) are represented by λ _PR , λ _PG , and λ _PB in FIG. 6A, respectively. Has been. Here, in any color filter, the maximum transmittance is 80% or more. For example, the predetermined transmittance is 50%, which is smaller than the maximum transmittance. In this case, the red color filter 122R, a wavelength showing 50% of a predetermined transmission rate less than lambda _PR is a lambda _LR in Figure 6A. From the above, the irradiation unit 11, in this step, when detecting a defective portion of the red light emitting pixel, selects a monochromatic light having a peak intensity at a wavelength lambda _LR as the first illumination light. Similarly, when detecting a defective portion of a green light emitting pixel, the irradiation unit 11 selects monochromatic light having a peak intensity at the wavelength λ _LG as the first irradiation light. Moreover, when detecting the defective part of a blue light emission pixel, the irradiation part 11 selects the monochromatic light which has peak intensity in wavelength (lambda) _LB as 1st irradiation light.

Thereby, when detecting the defective part of any light emitting pixel, when irradiating irradiation light having a peak intensity at a wavelength (λ _PR , λ _PG or λ _PB ) indicating the maximum transmittance in the visible light wavelength region. In comparison, since the detection resolution of the defect portion is improved, it is possible to detect a minute defect portion with high accuracy. When the predetermined transmittance is set to 50% as in the above example, for example, based on the ratio of λ _PR to λ _LR , the size is about 3/4 of the comparison target. It is possible to detect even those.

FIG. 6B is a second graph showing the relationship between the wavelength of the irradiation light used in the inspection method according to the embodiment of the present invention and the pass characteristics of the color filter. The figure shows a second example of wavelength-transmittance characteristics for the red color filter 122R, the green color filter 122G, and the blue color filter 122B. The wavelength-transmittance characteristic shown in FIG. 6B is different from the wavelength-transmittance characteristic of the first example shown in FIG. 6A in that the red color filter 122R has a wavelength λ _PR2 belonging to the purple region of 400 nm or less. This is a point having a sub-peak. Here, for example, the predetermined transmittance is set to 20% smaller than the maximum transmittance. In this case, the red color filter 122R, the shortest wavelength showing 20% of a predetermined transmission shorter than the wavelength lambda _PR1 of maximum transmittance is lambda _LR2 in Figure 6B. In this case, when the irradiation unit 11 detects a defective portion of the red light emitting pixel in this step, the irradiation unit 11 selects monochromatic light having a peak intensity at the wavelength _λLR2 as the first irradiation light. Similarly, when detecting a defective portion of the green light emitting pixel, the irradiation unit 11 selects monochromatic light having a peak intensity at the wavelength λ _LG2 as the first irradiation light. Moreover, when detecting the defective part of a blue light emission pixel, the irradiation part 11 selects the monochromatic light which has a peak intensity in wavelength (lambda _{) LB2} as 1st irradiation light.

As a result, when detecting a defective portion of any light emitting pixel, when irradiating irradiation light having a peak intensity at a wavelength (λ _PR1 , λ _PG or λ _PB ) indicating the maximum transmittance in the visible light wavelength region. In comparison, since the detection resolution of the defect portion is improved, it is possible to detect a minute defect portion with high accuracy. When the predetermined transmittance is set to 20% as in the above example, for example, based on the ratio of λ _PR1 and λ _LR2 , the size is about ½ of the comparison target. It is possible to detect even those.

  When the first irradiation light is irradiated, it is assumed that sufficient emission intensity cannot be obtained in the first optical image described in the next step because the attenuation by the color filter corresponding to the predetermined transmittance of 20% is large. Is done. However, since it is the light emitting pixel in which the color filter of the same color as the color filter is arranged that detects the defective portion by the irradiation of the first irradiation light, the first light irradiation light amount can be adjusted by adjusting the emission light amount of the first irradiation light. It is possible to obtain sufficient emission intensity in one optical image.

Next, the luminance measuring unit 12 acquires a first optical image of each light emitting pixel of the display panel 22 irradiated with the first irradiation light in step S201 by using a detector (S203). For example, a CCD camera is used as the detector. In the present step, for example, a monochromatic light of a wavelength lambda _LR which depends on the red color filter 122R and the peak wavelength in the case of the first irradiation light, for the purpose of detecting the defective portion of the red light-emitting pixel 22R The light emission luminance in the optical image of the red light emitting pixel 22R in the first optical image is measured. The luminance measuring unit 12 may adjust the exposure amount of the first optical image when measuring the emission luminance. Further, when the predetermined transmittance is set low, it is assumed that the S / N ratio in the first optical image is lowered. In this case, the luminance measurement unit 12 may include, for example, a high-sensitivity low-temperature CCD camera. Steps S201 and S203 are peaks at a wavelength shorter than the wavelength indicating the maximum transmittance in the visible light wavelength region of any one of the display color filters and exhibiting a predetermined transmittance in the visible light wavelength region. This corresponds to a short wavelength acquisition step of irradiating a plurality of display pixels with first irradiation light having intensity through a color filter and acquiring a first optical image of the plurality of display pixels at the time of the irradiation.

  Finally, the determination unit 13 identifies a defective portion of the light emitting pixel in which the color filter corresponding to the first irradiation light is arranged from the first optical image (S205). As a method for identifying a defective portion in this step, a portion showing a luminance value equal to or higher than a predetermined value in the obtained first optical image may be identified as a defective portion. In this defect portion identification method, there is a short-circuit defect portion or a defect portion having a locally thick film thickness between the anode and the cathode of the organic EL display element, and the display panel 22 is irradiated with the first irradiation light. In this case, the fact that the brightness of reflected light or scattered light from the defective portion becomes abnormally high is used. Step S205 corresponds to a defect detection step of detecting a defective portion of each color display pixel from the first optical image.

FIG. 7A is a diagram illustrating an optical image obtained by the display panel inspection method according to the embodiment of the present invention. (A), (b), and (c) of FIG. 7A were acquired in step S203 when the display panel 22 was irradiated with monochromatic light having peak intensities at wavelengths λ _LR , λ _LG , and λ _LB , respectively. It is a 1st optical image. As observed in (a) to (c) of FIG. 7A, an optical image of reflected light or scattered light of monochromatic light within the pass band of each color filter is obtained in each color light emitting pixel. Compared to the optical image generated by the visible light irradiation, it is possible to inspect the defective portion with high accuracy for each of the red light emitting pixel, the green light emitting pixel, and the blue light emitting pixel. In addition, detection of minute defects by irradiation with short wavelength light as compared with irradiation with infrared light shown in FIG. 7C and irradiation with monochromatic light having peak intensities at peak wavelengths λ _PR , λ _PG , and λ _PB . The accuracy has been improved.

  In the first inspection method, a lighting inspection by self-emission of each light emitting pixel may be performed before the defect detection by the irradiation of the first irradiation light in steps S201 to S205. As a result, the light emitting pixels that are normally lit and the abnormal light emitting pixels are discriminated, and steps S201 to S205 are performed only for the abnormal light emitting pixels, so that the inspection efficiency is improved. That is, in steps S201 to S205, only the first irradiation light corresponding to the color filter arranged in the abnormal light emitting pixel is irradiated, and only the abnormal light emitting pixel region in the acquired first optical image is measured for luminance. The first inspection method is suitable for detecting a defective portion for a specific light emitting pixel.

The first inspection method described above can be applied as an inspection method for inspecting a defective portion of any one of the red light emitting pixel, the green light emitting pixel, and the blue light emitting pixel, and the wavelengths λ _LR , λ _LG , and By combining three types of optical images obtained by irradiating the display panel 22 with monochromatic light having a peak intensity at _λLB , the defective portions of all the light-emitting pixels may be inspected. Hereinafter, the second inspection method will be described with a focus on differences from the first inspection method.

  FIG. 5B is an operation flowchart for explaining a second inspection method for the display panel according to the embodiment of the present invention.

First, the irradiation unit 11 irradiates the display panel 22 with second irradiation light having a peak intensity at a wavelength that is shorter than the wavelength indicating the maximum transmittance in the visible light region of the red color filter 122R and has a predetermined transmittance ( S202). At this time, the irradiation unit 11 focuses the second irradiation light on the surface of the display panel 22. In this step, for example, when the predetermined transmittance is set to 50%, the second irradiation light is _λLR shown in FIG.

  When the second irradiation light is irradiated, it is assumed that sufficient light emission intensity cannot be obtained in the second optical image described in the next step because the attenuation by the color filter corresponding to the predetermined transmittance is large. . However, it is possible to obtain a sufficient emission intensity in the second optical image by arbitrarily adjusting the amount of emitted light of the second irradiation light.

  Next, the luminance measuring unit 12 acquires a second optical image of each light emitting pixel of the display panel 22 irradiated with the second irradiation light in step S202 by using a detector (S204). For example, a CCD camera is used as the detector. Steps S202 and S204 show a predetermined transmittance in the visible light wavelength range, which is shorter than the wavelength indicating the maximum transmittance in the visible light wavelength range of the red color filter, to each color display pixel via the color filter. This corresponds to a red short wavelength acquisition step of irradiating the second irradiation light having the peak intensity at the second wavelength and obtaining the second optical image of each color display pixel at the time of the irradiation.

Next, the irradiation unit 11 irradiates the display panel 22 with third irradiation light having a peak intensity at a wavelength that is shorter than the wavelength indicating the maximum transmittance in the visible light region of the green color filter 122G and has a predetermined transmittance. (S206). At this time, the irradiation unit 11 focuses the third irradiation light on the surface of the display panel 22. In this step, for example, when the predetermined transmittance is set to 50%, the third irradiation light is λ _LG shown in FIG.

  In addition, when the said 3rd irradiation light is irradiated, since attenuation | damping by the color filter according to predetermined | prescribed transmittance | permeability is large, it is assumed that sufficient light emission intensity is not obtained in the 3rd optical image demonstrated at the next step. . However, it is possible to obtain sufficient light emission intensity in the third optical image by arbitrarily adjusting the amount of emitted light of the third irradiation light.

  Next, the luminance measurement unit 12 acquires a third optical image of each light emitting pixel of the display panel 22 irradiated with the third irradiation light in step S206 by using a detector (S208). For example, a CCD camera is used as the detector. Steps S206 and S208 show each color display pixel through the color filter at a wavelength shorter than the wavelength indicating the maximum transmittance in the visible light wavelength region of the green color filter and exhibit a predetermined transmittance in the visible light wavelength region. This corresponds to a green short wavelength acquisition step of irradiating the third irradiation light having the peak intensity at the third wavelength and obtaining the third optical image of each color display pixel at the time of the irradiation.

Next, the irradiation unit 11 irradiates the display panel 22 with fourth irradiation light having a peak intensity at a wavelength that is shorter than the wavelength indicating the maximum transmittance in the visible light region of the blue color filter 122B and has a predetermined transmittance. (S210). At this time, the irradiation unit 11 focuses the fourth irradiation light on the surface of the display panel 22. In this step, for example, when the predetermined transmittance is set to 50%, the fourth irradiation light is λ _LB shown in FIG.

  Note that, when the fourth irradiation light is irradiated, the attenuation due to the color filter corresponding to the predetermined transmittance is large, so that it is assumed that sufficient emission intensity cannot be obtained in the fourth optical image described in the next step. . However, it is possible to obtain a sufficient emission intensity in the fourth optical image by arbitrarily adjusting the amount of emitted light of the fourth irradiation light.

  Next, the luminance measurement unit 12 acquires a fourth optical image of each light emitting pixel of the display panel 22 irradiated with the fourth irradiation light in step S210 by using a detector (S212). For example, a CCD camera is used as the detector. Steps S210 and S212 show each color display pixel through the color filter at a wavelength shorter than the wavelength indicating the maximum transmittance in the visible light wavelength region of the blue color filter and exhibit a predetermined transmittance in the visible light wavelength region. This corresponds to a blue short wavelength acquisition step of irradiating fourth irradiation light having a peak intensity at the fourth wavelength and obtaining a fourth optical image of each color display pixel at the time of the irradiation.

  Finally, the determination unit 13 inspects all light-emitting pixels from the second optical image acquired in step S204, the third optical image acquired in step S208, and the fourth optical image acquired in step S212. Then, the defective part is specified (S214). Specifically, the determination unit 13 identifies defective portions for all the light-emitting pixels from an image obtained by combining the second optical image, the third optical image, and the fourth optical image. At this time, the luminance measurement unit 12 or the determination unit 13 corrects a difference in detection accuracy of the defective portion among the red light emitting pixel, the green light emitting pixel, and the blue light emitting pixel, and sets the predetermined transmittance and each optical image. The exposure amount of each optical image may be arbitrarily adjusted according to the brightness and contrast of the image.

  As a method for specifying a defective portion in this step, a portion showing a luminance value of a predetermined value or more in the second to fourth optical images may be specified as a defective portion. In this defect portion specifying method, a short-circuit defect portion or a defect portion having a locally thick film thickness of the light emitting layer exists between the anode and the cathode of the organic EL display element, and the display panel 22 is irradiated with the second to fourth irradiations. When light is irradiated, the fact that the brightness of reflected light or scattered light from the defect portion becomes abnormally high is used. Step S214 corresponds to a defect detection step of detecting a defective portion of each color display pixel from the first optical image.

(D) of FIG. 7A is an image obtained by synthesizing the second to fourth optical images obtained by irradiating the display panel 22 with monochromatic light having peak intensities at wavelengths λ _LR , λ _LG , and λ _LB. . As observed in (d) of FIG. 7A, an optical image of reflected light or scattered light of monochromatic light within the passband of each color filter is obtained in each color light emitting pixel, so that the visible light shown in FIG. 7B is obtained. Compared to the optical image by irradiation, it is possible to inspect the defective portion with high accuracy for each of the red light emitting pixel, the green light emitting pixel, and the blue light emitting pixel. In addition, detection of minute defects by irradiation with short wavelength light as compared with irradiation with infrared light shown in FIG. 7C and irradiation with monochromatic light having peak intensities at peak wavelengths λ _PR , λ _PG , and λ _PB . The accuracy has been improved.

  As described above, according to the first inspection method and the second inspection method for the display panel according to the embodiment of the present invention, the light-emitting pixel having the color filter is shorter than the wavelength indicating the maximum transmittance in the visible light wavelength region. The defective portion of the light-emitting pixel is specified by the optical image obtained by irradiating the irradiation light having the peak intensity at the wavelength at which the transmittance becomes. Thereby, the detection resolution of a defect part improves compared with the case where the irradiation light which has peak intensity in the wavelength which shows the maximum transmittance | permeability in a visible light wavelength range is irradiated. Therefore, it is possible to detect a minute defect portion with high accuracy.

  In the second inspection method described above, the second irradiation light irradiation and the second optical image acquisition for detecting the defective portion of the red light emitting pixel, the third irradiation light irradiation and the second optical image acquisition for detecting the defective portion of the green light emitting pixel are performed. Although an example in which the three optical images are acquired, the fourth irradiation light irradiation for detecting the defective portion of the blue light emitting pixel, and the fourth optical image acquisition is described in this order, the order of executing the three primary colors is arbitrary.

  Hereinafter, the repair process of step S30 will be described.

  In step S30, the defective device identified in step S20 is repaired by the repair device 3. The repair device 3 includes, for example, a laser oscillator, a detector, a CCD camera, illumination, and a stage. The display panel 22 is fixedly disposed on the stage. Then, for example, the laser focus is set on the cathode 116 in the vicinity of the defective portion of the display panel 22 to increase the resistance of a part of the cathode 116. The CCD camera is a monitor that observes the surface of the display panel 22 on the stage in order to adjust the height and plane direction of the stage with high accuracy. Thus, for example, a cathode region that is electrically short-circuited with a foreign material, that is, a cathode region surrounded by a part of the cathode is insulated from other cathode regions and short-circuited to the anode 112 via the foreign material. Yes. Thereby, the current path flowing between the anode 112 and the cathode 116 does not occur in the cathode region surrounded by a part of the cathode, but normally occurs in the cathode region other than the cathode region. Step S30 corresponds to a repair process for repairing the defective portion detected in step S206 or S209.

  Finally, it is confirmed whether or not the light emitting pixel having the defective portion has been recovered by the laser repair described above.

  FIG. 8 is a diagram illustrating the lighting confirmation after the laser repair. For example, when a predetermined signal voltage is supplied to a luminescent pixel in which a short-circuit defect portion due to a foreign substance exists, only the short-circuit defect portion becomes a bright spot. On the other hand, after laser repair is performed, for example, the laser repair increases the resistance of the short-circuit defect portion to become a black spot, and the light emitting region other than the short-circuit defect portion emits light. By confirming the lighting in such a light emission mode, it is possible to confirm whether or not the light emitting pixels can be restored.

  As described above, according to the manufacturing method of the display panel of the present invention, the minute defect portion of the light emitting pixel is formed by irradiating the irradiation light having the peak intensity at a wavelength shorter than the wavelength indicating the maximum transmittance in the visible light wavelength region of the color filter. It becomes possible to detect with high accuracy. This highly accurate detection of a defective portion can surely carry out repair of the defective portion, so that the manufacturing yield is improved.

  Although the display panel manufacturing method, the inspection apparatus, and the inspection method according to the present invention have been described based on the above-described embodiments, the present invention is not limited to the above-described embodiments. Another embodiment realized by combining arbitrary constituent elements in the embodiment, or modifications obtained by applying various modifications conceivable by those skilled in the art without departing from the gist of the present invention to the embodiment. Various devices incorporating the display panel according to the present invention are also included in the present invention.

  In the above embodiment, the case where the foreign substance 50 exists across the organic layer is exemplified as the defective portion of the light emitting pixel to be detected. However, the defective portion detected by the inspection apparatus and the inspection method of the present invention is not limited to this. I can't. As the defect portion, in addition to the short-circuit defect due to the foreign substance 50, for example, the aspect in which the foreign substance 50 is not present but the anode 112 and the cathode 116 are short-circuited without the organic layer interposed therebetween, or the light emitting layer 114 is locally thick. And the like. Hereinafter, the two aspects will be described with reference to the drawings.

  FIG. 9A is a schematic cross-sectional view of a light-emitting pixel according to a first modification of the embodiment of the present invention. The green light emitting pixel 22G according to this modification is different from the green light emitting pixel 22G shown in FIG. Is a point. This is because, for example, a pinhole is formed at the position of the short-circuit portion in the organic layer forming process, and then the material constituting the cathode 116 flows into the pinhole in the cathode 116 forming process to form the cathode 116. In addition, it is in direct contact in this way. Also in such an aspect, the defect part 51 is detected as an abnormal bright spot by irradiating the irradiation light having the peak intensity at a wavelength shorter than the wavelength showing the maximum transmittance in the visible light wavelength region of the color filter. Then, by increasing the resistance of the defective portion 51, it is possible to eliminate the short circuit between the shorted anode 112 and the cathode 116.

  FIG. 8B is a schematic cross-sectional view of a luminescent pixel according to a second modification of the embodiment of the present invention. The green light emitting pixel 22G according to this modification is different from the green light emitting pixel 22G described in FIG. 3B in that the light emitting layer 114 is locally thick. Also in such an aspect, the defect part 52 is detected as an abnormal bright spot by irradiating the irradiation light having the peak intensity at a wavelength shorter than the wavelength showing the maximum transmittance in the visible light wavelength region of the color filter. And it is possible to eliminate the defect by increasing the resistance of the defect portion 52.

  In the above-described embodiment, the configuration in which the lower electrode is an anode and the upper electrode is a cathode is shown, but the lower electrode may be a cathode and the upper electrode may be an anode. Further, the planarization film, anode, hole injection layer, light emitting layer, partition wall, electron injection layer, cathode, thin film sealing layer, sealing resin layer, color filter, adhesive layer and transparent substrate, which are the structures of the light emitting pixels, The material, the configuration, and the forming method are not limited to the configuration described in the above embodiment. For example, a hole transport layer may be provided between the hole injection layer and the light emitting layer, or an electron transport layer may be provided between the electron injection layer and the light emitting layer.

  Further, the laser irradiation position in the laser repair is not limited to the above-described embodiment, and may be set to a predetermined range including a foreign object or a short-circuited part, or may be set only to a foreign object or a short-circuited part. Moreover, you may set so that the circumference | surroundings of a foreign material and a short circuit part may be enclosed. Laser irradiation is not limited to the cathode and may be performed on the anode.

  Further, the present invention is suitable for manufacturing a thin flat television system including a light emitting panel according to the manufacturing method of the present invention as shown in FIG.

  Further, the inspection device 1 described in FIG. 1 may be incorporated in the display device 2. In this case, the control unit 21 of the display device 2 includes the irradiation unit 11, the luminance measurement unit 12, and the determination unit 13, and the control unit 21 executes the inspection method described in the embodiment. Also according to this aspect, it is possible to irradiate irradiation light having a peak intensity at a wavelength shorter than the wavelength exhibiting the maximum transmittance described above, thereby detecting a minute defect portion with high accuracy, and reliably repairing the defect portion. Since it can be executed, the manufacturing yield is improved.

  In the above embodiment, the visible light region is a region having a wavelength of 380 nm to 800 nm. The red color filter 122R is a filter having a red region as a main passband. The green color filter 122G is a filter having a green region as a main pass band. The blue color filter 122B is a filter having a blue region as a main pass band. Here, the red region is a region having a wavelength of 600 to 800 nm. The green region is a region having a wavelength of 500 to 600 nm. The blue region is a region having a wavelength of 380 to 500 nm. The wavelength of infrared light is 800 nm to 1 μm.

  The display panel manufacturing method, the inspection apparatus, and the inspection method according to the present invention are useful in technical fields such as a flat-screen television and a display of a personal computer that require a large screen and high resolution.

DESCRIPTION OF SYMBOLS 1 Inspection apparatus 2 Display apparatus 3 Repair apparatus 11 Irradiation part 12 Luminance measurement part 13 Judgment part 21 Control part 22 Display panel 22B Blue light emission pixel 22G Green light emission pixel 22R Red light emission pixel 23 Data line drive circuit 24 Scan line drive circuit 50 Foreign material 51 , 52 Defective part 110 Substrate 111 Planarization film 112 Anode 113 Hole injection layer 114 Light emitting layer 115 Electron injection layer 116 Cathode 117 Thin film sealing layer 118 Sealing resin layer 119 Adhesive layer 120 Transparent substrate 121 Black matrix 122 Color filter 122B Blue color filter 122G Green color filter 122R Red color filter 123 Bulkhead 130 Organic layers 221, 421 Organic EL element 222 Drive transistor 223 Select transistor 224 Capacitor 231 Data line 241 Scan line 25 A positive power supply line 261 a negative power supply line 422 shorted component

Claims (9)

A method for inspecting a display panel comprising a plurality of display pixels having different display colors and having a color filter including a display color filter arranged corresponding to the display color of the display pixels,
The display color filter has a peak intensity at a wavelength shorter than a wavelength indicating the maximum transmittance in the visible light wavelength region and having a predetermined transmittance in the visible light wavelength region. A short wavelength acquisition step of irradiating a plurality of display pixels with one irradiation light through the color filter, and acquiring a first optical image of the plurality of display pixels at the time of the irradiation;
A defect detection step of detecting a defect portion of a display pixel in which the display color filter is arranged from the first optical image,
In the defect detection step, a region where the luminance value measured by the first optical image is a predetermined value or more is determined as the defect portion ,
There are a plurality of wavelengths that are shorter than the wavelength indicating the maximum transmittance in the visible light wavelength region of the display color filter among the display color filters and exhibit a predetermined transmittance in the visible light wavelength region,
In the short wavelength acquisition step, a display panel inspection method in which the display pixel is irradiated with the first irradiation light having a peak intensity at the shortest wavelength among the plurality of wavelengths . A display panel inspection method including a red display pixel, a green display pixel, and a blue display pixel, and a color filter including a red filter, a green filter, and a blue filter arranged corresponding to each color display pixel,
In each color display pixel via the color filter, the second wavelength is shorter than the wavelength indicating the maximum transmittance in the visible light wavelength region of the red filter and exhibits a predetermined transmittance in the visible light wavelength region. A short red wavelength acquisition step of irradiating a second irradiation light having a peak intensity and obtaining a second optical image of each color display pixel at the time of the irradiation;
A third wavelength which is shorter than the wavelength indicating the maximum transmittance in the visible light wavelength region of the green filter and has the predetermined transmittance in the visible light wavelength region to each color display pixel via the color filter. Irradiating the third irradiation light having a peak intensity in the step of obtaining a green short wavelength acquisition step of obtaining a third optical image of each color display pixel at the time of the irradiation,
A fourth wavelength which is shorter than the wavelength indicating the maximum transmittance in the visible light wavelength range of the blue filter and has the predetermined transmittance in the visible light wavelength range to each color display pixel via the color filter. A blue short wavelength acquisition step of irradiating with a fourth irradiation light having a peak intensity in to obtain a fourth optical image of each color display pixel at the time of the irradiation;
A defect detection step of detecting a defect of each color display pixel from the second optical image, the third optical image, and the fourth optical image,
In the defect detection step, an area in which the luminance value measured by the second optical image, the third optical image, and the fourth optical image is a predetermined value or more is determined as the defect portion. . In the red short wavelength acquisition step, when there are a plurality of the second wavelengths, the display pixel is irradiated with the second irradiation light having a peak intensity at the shortest wavelength among the plurality of the second wavelengths,
In the green short wavelength acquisition step, when there are a plurality of the third wavelengths, the display pixel is irradiated with the third irradiation light having a peak intensity at the shortest wavelength among the plurality of the third wavelengths,
In the blue short wavelength acquisition step, when there are a plurality of the fourth wavelengths, the display pixel is irradiated with the fourth irradiation light having a peak intensity at the shortest wavelength among the plurality of the fourth wavelengths. 3. The display panel inspection method according to 2. In the defect detection step, the second optical image, to claim 2 for detecting a defect of each of the color display pixels the third optical image and an exposure amount of said fourth optical image from the image synthesized by adjusting each optionally Inspection method of display panel of description. Each color display pixel has an organic electroluminescence light emitting layer sandwiched between a cathode and an anode,
The defect in the detection step, the inspection method of a display panel according to any one of claims 1-4 for detecting said cathode and said defective portion the anode are short-circuited. A display panel including a red display pixel, a green display pixel, and a blue display pixel, and having a color filter including a red filter, a green filter, and a blue filter arranged corresponding to each color display pixel, the color filter through the color filter Each color display pixel has a second irradiation having a peak intensity at a second wavelength which is shorter than a wavelength indicating the maximum transmittance in the visible light wavelength region of the red filter and exhibits a predetermined transmittance in the visible light wavelength region. Irradiate light, and each color display pixel through the color filter has a wavelength shorter than the wavelength indicating the maximum transmittance in the visible light wavelength region of the green filter and has a predetermined transmittance in the visible light wavelength region. The third irradiating light having the peak intensity at the third wavelength shown is irradiated, and the blue color filter is applied to each color display pixel via the color filter. An irradiation unit for irradiating a fourth irradiation light having a peak intensity in the fourth wavelength exhibiting a predetermined transmittance in the visible light wavelength region by a wavelength shorter than the wavelengths showing the maximum transmittance in the visible light wavelength region of,
While the second irradiation light is irradiated from the irradiation unit, a second optical image of each color display pixel is acquired, and each color display is performed while the third irradiation light is irradiated from the irradiation unit. A luminance measuring unit that acquires a third optical image of the pixel and acquires a fourth optical image of each color display pixel while the fourth irradiation light is irradiated from the irradiation unit;
A display panel inspection apparatus comprising: a determination unit that determines, as a defective portion, a region in which a luminance value measured by the second optical image, the third optical image, and the fourth optical image is equal to or greater than a predetermined value. A method of manufacturing a display panel including a red display pixel, a green display pixel, and a blue display pixel, and having a color filter including a red filter, a green filter, and a blue filter arranged corresponding to each color display pixel,
A display pixel forming step of forming the red display pixels, the green display pixels, and the blue display pixels in a matrix on a display panel substrate, and forming the color filter on each of the color display pixels;
In each color display pixel via the color filter, the second wavelength is shorter than the wavelength indicating the maximum transmittance in the visible light wavelength region of the red filter and exhibits a predetermined transmittance in the visible light wavelength region. A short red wavelength acquisition step of irradiating a second irradiation light having a peak intensity and obtaining a second optical image of each color display pixel at the time of the irradiation;
A third wavelength which is shorter than the wavelength indicating the maximum transmittance in the visible light wavelength region of the green filter and has the predetermined transmittance in the visible light wavelength region to each color display pixel via the color filter. Irradiating the third irradiation light having a peak intensity in the step of obtaining a green short wavelength acquisition step of obtaining a third optical image of each color display pixel at the time of the irradiation,
A fourth wavelength which is shorter than the wavelength indicating the maximum transmittance in the visible light wavelength range of the blue filter and has the predetermined transmittance in the visible light wavelength range to each color display pixel via the color filter. A blue short wavelength acquisition step of irradiating with a fourth irradiation light having a peak intensity in to obtain a fourth optical image of each color display pixel at the time of the irradiation;
A defect detection step of detecting, as a defect portion, a region where the luminance value measured by the second optical image, the third optical image, and the fourth optical image is a predetermined value or more;
A repair process for repairing the defective portion detected in the defect detection process. A method for inspecting a display panel comprising a plurality of display pixels having different display colors and having a color filter including a display color filter arranged corresponding to the display color of the display pixels,
The display color filter has a peak intensity at a wavelength shorter than a wavelength indicating the maximum transmittance in the visible light wavelength region and having a predetermined transmittance in the visible light wavelength region. A short wavelength acquisition step of irradiating a plurality of display pixels with one irradiation light through the color filter, and acquiring a first optical image of the plurality of display pixels at the time of the irradiation;
A defect detection step of detecting a defect portion of a display pixel in which the display color filter is arranged from the first optical image,
There are a plurality of wavelengths that are shorter than the wavelength indicating the maximum transmittance in the visible light wavelength region of the display color filter among the display color filters and exhibit a predetermined transmittance in the visible light wavelength region,
In the short wavelength acquisition step, the display pixel is irradiated with the first irradiation light having a peak intensity at the shortest wavelength among the plurality of wavelengths. A display panel inspection method including a red display pixel, a green display pixel, and a blue display pixel, and a color filter including a red filter, a green filter, and a blue filter arranged corresponding to each color display pixel,
In each color display pixel via the color filter, the second wavelength is shorter than the wavelength indicating the maximum transmittance in the visible light wavelength region of the red filter and exhibits a predetermined transmittance in the visible light wavelength region. A short red wavelength acquisition step of irradiating a second irradiation light having a peak intensity and obtaining a second optical image of each color display pixel at the time of the irradiation;
A third wavelength which is shorter than the wavelength indicating the maximum transmittance in the visible light wavelength region of the green filter and has the predetermined transmittance in the visible light wavelength region to each color display pixel via the color filter. Irradiating the third irradiation light having a peak intensity in the step of obtaining a green short wavelength acquisition step of obtaining a third optical image of each color display pixel at the time of the irradiation,
A fourth wavelength which is shorter than the wavelength indicating the maximum transmittance in the visible light wavelength range of the blue filter and has the predetermined transmittance in the visible light wavelength range to each color display pixel via the color filter. A blue short wavelength acquisition step of irradiating with a fourth irradiation light having a peak intensity in to obtain a fourth optical image of each color display pixel at the time of the irradiation;
A defect detection step of detecting a defect of each color display pixel from the second optical image, the third optical image, and the fourth optical image,
In the red short wavelength acquisition step, when there are a plurality of the second wavelengths, the display pixel is irradiated with the second irradiation light having a peak intensity at the shortest wavelength among the plurality of the second wavelengths,
In the green short wavelength acquisition step, when there are a plurality of the third wavelengths, the display pixel is irradiated with the third irradiation light having a peak intensity at the shortest wavelength among the plurality of the third wavelengths,
In the blue short wavelength acquisition step, when there are a plurality of the fourth wavelengths, the display pixel is irradiated with the fourth irradiation light having a peak intensity at the shortest wavelength among the plurality of the fourth wavelengths. Inspection method.