JPH0317341B2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a cathode ray tube (hereinafter referred to as "CRT")
The present invention relates to an alignment device for aligning structures and parts inside a vacuum container such as a vacuum container.

Conventional Structure and Problems In conventional CRTs, the shadow mask and the phosphor surface have been aligned by a direct exposure method, in which the phosphor is coated in line with the shadow mask. In this case, there must be a one-to-one correspondence between the shadow mask and the face surface coated with the phosphor, and the process must be carried out with the shadow mask and the face surface as a pair.

On the other hand, in a flat display device, due to its structure,
The number of electrodes that must be aligned is large, making it impossible to use the direct exposure method used in conventional CRTs. Also,
This configuration has a large number of control blocks, so
Even if the containers are aligned before sealing, misalignment may occur due to differences in expansion coefficients due to temperature rise during sealing and deformation of the container after vacuuming, and the electron beam may not be placed in the correct phosphor position. I had a problem with it becoming impossible to hit.

OBJECTS OF THE INVENTION The present invention solves the above-mentioned conventional drawbacks, and an object of the present invention is to provide a positioning device that can perform positioning adjustment after evacuation.

Structure of the Invention The alignment device of the present invention has a bellows which is tightly fixed to a container filled with a vacuum or low-pressure special gas in a state that closes a hole in the container, and is made of a metal whose expansion coefficient matches that of the material of the container. and an adjusting means for moving and aligning the structure inside the container from outside the container via the bellows.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

First, a flat panel display device will be described with reference to FIGS. 1 to 3 as an example of a vacuum container in which alignment is performed using an alignment device according to an embodiment of the present invention. Conventionally, cathode ray tubes have been mainly used as display elements for displaying color television images, but conventional cathode ray tubes have a very long depth compared to the screen size, making it difficult to create thin television receivers. It was impossible. In addition, EL display elements, plasma display devices, liquid crystal display elements, etc. have recently been developed as flat display elements, but all of them have low brightness, contrast, etc.
It is insufficient in terms of performance such as color reproducibility in color display, and has not yet been put into practical use. Therefore, the aim was to create a device that could display color television images on a flat display device using electron beams, and the screen was divided vertically into multiple sections. Each section generates an electron beam, deflects each electron beam in the vertical direction to display multiple lines, and further divides it into multiple sections horizontally to display R, G, B, etc. phosphors are made to emit light in sequence, and the amount of electron beam irradiation to the R, G, B, etc. phosphors is controlled by a color video signal, and the television image as a whole is displayed. Something to display was devised. First, a basic configuration example of the image display element used here will be explained with reference to FIG. This display element includes, in order from the back to the front, a back electrode 1, a line cathode 2 as an electron beam source, vertical focusing electrodes 3, 3', a vertical deflection electrode 4, an electron beam flow control electrode 5, and a horizontal focusing electrode 6. , a horizontal deflection electrode 7, an electron beam acceleration electrode 8, and a screen plate 9 are arranged.
These are housed inside a flat glass bulb (not shown) filled with vacuum or low-pressure special gas. A line cathode 2 serving as an electron beam source is stretched horizontally so as to generate an electron beam distributed linearly in the horizontal direction. So 2
Only four (a to 2d are shown)] are provided. In this embodiment, it is assumed that 15 pieces are provided, and these are designated as 2a to 2o. These line cathodes 2
For example, it is constructed by coating an oxide cathode material on the surface of a tungsten wire with a diameter of 10 to 20 μm. Then, as described later, the upper line cathode 2a
The electron beam is controlled to be emitted sequentially for a fixed period of time. The back electrode 1 creates a potential gradient with the vertical focusing electrode 3, suppresses generation of electron beams from other line cathodes 2 other than the line cathode 2 controlled to emit electron beams for a certain period of time, and , which functions to push the generated electron beam only in the forward direction. The back electrode 1 may be formed by a coating of a conductive material applied to the inner surface of the rear wall of the glass bulb. In addition, these back electrodes 1
Instead of the linear cathode 2, a planar electron beam emitting cathode may be used.

The vertical focusing electrode 3 is composed of a conductive plate 11 having a horizontally long slit 10 facing each of the line cathodes 2a to 2o, and extracts the electron beam emitted from the line cathode 2 through the slit 10, and , vertically focused. The slit 10 may be provided with crosspieces at appropriate intervals in the middle, or may be substantially configured as a slit by a row of many through holes arranged horizontally at small intervals (nearly touching intervals). may have been done. The vertical focusing electrode 3' is also similar.

A plurality of vertical deflection electrodes 4 are arranged horizontally in the middle of each of the slits 10, and are each composed of conductors 13 and 13' provided on the upper and lower surfaces of an insulating substrate 12. has been done. And the opposing conductors 13, 13'
A vertical deflection voltage is applied between them to deflect the electron beam in the vertical direction. In this configuration example, a pair of conductors 13 and 13' deflect the electron beam from one line cathode 2 to a position corresponding to 16 lines in the direction perpendicular to the sushi. And by 16 vertical deflection electrodes 4
15 conductor pairs corresponding to each of the 15 wire cathodes 2 are constructed, and in the end, 240 conductor pairs are arranged on the screen plate 9.
The electron beam is deflected to draw a horizontal line on the book.

Next, the electron beam flow control electrodes 5 are composed of conductive plates 15 each having a vertically long slit 14, and a plurality of them are arranged in parallel in the horizontal direction at predetermined intervals. In this configuration example, 320 control electrode conductive plates 15a to 15n are provided (only 10 are shown in the figure). Each of the electron beam flow control electrodes 5 divides the electron beam horizontally into one picture element and takes out the electron beam, and controls the amount of the electron beam passing in accordance with a video signal for displaying each picture element. . Therefore, if 320 electron beam flow control electrodes 5 are provided, 320 pixels can be displayed per horizontal line. In addition, in order to display images in color, each picture element is displayed using phosphors of three colors, R, G, and B, and each electron beam flow control electrode 5 is provided with each of the R, G, and B colors. Video signals are added sequentially. Furthermore, 320 sets of video signals for one line are simultaneously applied to the 320 electron beam flow control electrodes 5, and the video for one line is displayed at one time.

The horizontal focusing electrode 6 is composed of a conductive plate 17 having a plurality of vertically long slits 16 (320 slits 16) facing the slits 14 of the electron beam flow control electrode 5, and each of the horizontally divided picture elements Each electron beam is focused horizontally into a narrow electron beam.

The horizontal deflection electrode 7 is composed of a plurality of conductive plates 18 arranged vertically in the middle of each of the slits 16, and a horizontal deflection voltage is applied between each of the conductive plates 18 for each pixel. The screen plate 9 deflects the electron beams horizontally.
Each of the R, G, and B phosphors is sequentially irradiated on the top to emit light. In this embodiment, the deflection range is the width of one picture element for each electron beam.

The electron beam accelerating electrode 8 is composed of a plurality of conductive plates 19 provided horizontally at the same position as the vertical deflection electrode 4, and accelerates the electron beam so that it collides with the screen plate 9 with sufficient energy. do.

The screen plate 9 is constructed by applying a phosphor 20 that emits light when irradiated with an electron beam to the back surface of a glass plate 21, and adding a metal back layer (not shown). The phosphors 20 are phosphors of three colors R, G, and B for one slit 14 of the electron beam flow control electrode 5, that is, for each one electron beam divided in the horizontal direction. are provided in pairs, and are applied in stripes in the vertical direction. In FIG. 1, the broken lines drawn on the screen plate 9 indicate divisions in the vertical direction corresponding to the plurality of line cathodes 2, and the two-dot chain lines indicate the divisions in the vertical direction corresponding to the plurality of line cathodes 2. The horizontal divisions displayed corresponding to each are shown. As shown in the enlarged view in Fig. 2, one section partitioned by these two has R, G, and B phosphors 20 for one picture element in the horizontal direction, and 16 in the vertical direction.
It has the width of a line. For example, the size of one section is 1 mm horizontally and 16 mm vertically.
It is.

Note that in FIG. 1, the length in the horizontal direction is greatly enlarged relative to the length in the vertical direction for clarity.

In addition, in this configuration example, R,
Although only one pair of G and B phosphors 20 is provided for one picture element, it is of course possible to provide two or more pairs for two or more picture elements, and in that case, the electron beam flow control electrode 5 R, G, for two or more picture elements,
A B video signal is sequentially applied, and horizontal deflection is performed in synchronization with it.

Next, the basic configuration of a drive circuit for displaying television images on this display element will be explained with reference to FIG. First, the electron beam is passed through the screen plate 9.
A driving portion for causing the phosphor 20 to emit light and generating a raster will be described.

The power supply circuit 22 is a circuit for applying a predetermined bias voltage (operating voltage) to each electrode of the display element,
-V ₁ to the back electrode 1, and -V 1 to the vertical focusing electrodes 3 and 3'.
DC voltages of V ₃ , V′ ₃ , V ₆ to the horizontal focusing electrode 6 , V ₈ to the electron beam accelerating electrode 8 , and V _{9 to the screen plate 9} are applied.

Next, a composite video signal of a television signal is applied to the input terminal 23, and a synchronization separation circuit 24 separates and extracts a vertical synchronization signal V and a horizontal synchronization signal H. The vertical drive pulse generation circuit 25 is composed of a counter that is reset by a vertical retrace pulse and counts horizontal pulses, and the vertical retrace pulse generation circuit 25 is configured with a counter that is reset by a vertical retrace pulse and counts horizontal pulses, and the vertical retrace pulse generation circuit 25 is configured to operate during an effective vertical scanning period (here, 240H) excluding the vertical retrace period of the vertical period. 15 drive pulses [A, B...Y] each having a length of 16H are sequentially generated during each period of 16H. These drive pulses [A, B...Y] were applied to the line cathode drive circuit 26, where they were inverted and brought to a low potential only during each pulse period, and to a high potential of approximately 20 volts during the rest of the time. The pulses are converted into line cathode drive pulses [A', B'...Yo'] and applied to each line cathode 2a, 2b...2o. A current is passed through each line cathode 2a...2o during the high potential period of the driving pulse [A' to Y'], and electrons can be emitted even during the low potential period of the driving pulse [A' to Y']. The heated state is maintained. As a result, electrons are emitted from the 15 linear cathodes 2a to 2o only during the 16H period when low potential drive pulses [A' to Y'] are applied to each of them. During the period when a high potential is applied, the potential applied to the line cathodes 2a to 2o is higher than the potential at the position of the line cathode 2 determined by the bias voltage applied to the back electrode 1 and the vertical focusing electrode 3. Since the higher potential is positive, no electrons are emitted from the line cathodes 2a to 2o. Thus, in the line cathode 2, electrons are sequentially emitted from the upper line cathode 2a toward the lower line cathode 2o for 16H periods during the effective vertical scanning period. The emitted electrons are pushed forward by the back electrode 1, pass through the opposing slits 10 of the vertical focusing electrode 3, and are focused in the vertical direction to form a flat electron beam.

Next, the vertical deflection drive circuit 27 is composed of a counter that is reset by each of the vertical drive pulses [I to Y] and counts the horizontal synchronization signal, a conversion circuit that converts the count output from D/A, and the like. and each vertical drive pulse [I to Y]
A pair of vertical deflection signals v and v' are generated that change in 16 steps by 1H during a 16H period. Vertical deflection signal v
and v' both have a center voltage of _V4 , and are configured to change in opposite directions so that v increases sequentially and v' decreases sequentially. These vertical deflection signals v and v' are respectively applied to the conductors 13 and 13' of the vertical deflection electrode 4, and as a result, the electron beams generated from the respective line cathodes 2a to 2o are vertically deflected in 16 steps. As mentioned above, one electron beam is deflected on the screen plate 9 so that a raster of 16 lines is drawn one line at a time from the top.

As a result of the above, electron beams are emitted for 16H periods in order from the one above the 15 line cathodes 2a to 2o.
Each electron beam is sequentially deflected by one line from above to below within the 15 vertical divisions, so that on the screen plate 9, it is sequentially deflected from the 1st line at the top end to the 240th line at the bottom end. The electron beam is vertically deflected one line at a time, creating a total of 240 raster lines.

The electron beam thus vertically deflected is horizontally divided into 320 sections and extracted by the electron beam flow control electrode 5 and the horizontal focusing electrode 6.
Figure 1 shows one of these categories. The passing amount of this electron beam is controlled for each section by an electron beam flow control electrode 5, and is focused horizontally by a horizontal focusing electrode 6 into a single thin electron beam, which is then horizontally deflected as described below. The light is deflected in the horizontal direction in three stages by means of means, and is sequentially irradiated onto each of the R, G, and B phosphors 20 on the screen plate 9.

That is, the horizontal drive pulse generation circuit 28 is composed of three cascaded monostable multivibrators, etc., and is triggered by a horizontal synchronization signal to generate three horizontal drives with equal pulse widths within one horizontal period. Generate pulses r, g, b. Here, as an example, each pulse width is approximately 17 μsec.
3 during the effective horizontal scanning period of 50μsec.
Three pulses r, g, and b are generated. These horizontal drive pulses r, g, and b are applied to the horizontal deflection drive circuit 29. The water deflection drive circuit 29 generates a pair of horizontal deflection signals h and h' that change in three stages by being switched by the horizontal drive pulses r, g, and b. Both horizontal deflection signals h and h' have a center voltage of V ₇ , and h increases sequentially,
h' change in opposite directions so that they decrease sequentially. These horizontal deflection signals h, h' are applied to the conductive plates 18 and 18' of the horizontal deflection electrode 7, respectively. As a result, each horizontally divided electron beam is transmitted to the screen plate 9 from R to G during each horizontal period.
It is horizontally deflected so that the phosphor B is sequentially irradiated for 17 μsec each.

Thus, in each line raster, the electron beam is divided into R, G,
Each phosphor 20 of B is sequentially irradiated.

Therefore, a color television image can be displayed on the screen plate 9 by modulating the electron beam with R, G, and B video signals for each horizontal section of each line.

Next, the modulation control portion of the electron beam will be explained.

First, the composite video signal applied to the television signal input terminal 23 is applied to the color demodulation circuit 30,
Here, the color difference signals of R-Y and B-Y are demodulated,
The G-Y color difference signals are matrix-synthesized, and further, they are combined with the luminance signal Y to generate R, G,
B primary color signals (hereinafter referred to as R, G, and B video signals) are output. These R, G, and B video signals are processed by 320 sample and hold circuit sets 31a to 3.
Added to 1n. Each sample hold circuit group 3
Each of the circuits 1a to 31n has three sample and hold circuits for R, G, and B. The sample and hold outputs of these sample and hold circuit sets 31a to 31n are held by memory sets 32a to 32n, respectively.
32n.

On the other hand, the sampling reference clock oscillator 33
is composed of a PLL (phase locked loop) circuit, etc., and generates a reference clock of about 6.4 MHz in this embodiment. The reference clock is controlled to always have a constant phase with respect to the horizontal synchronizing signal H. This reference clock is applied to the sampling pulse generation circuit 34, where it is delayed by one clock cycle by a shift register, etc., so that the reference clock is applied to the sampling pulse generating circuit 34, where it is delayed by one clock period, etc. Sampling pulses a to n are sequentially generated, and then one transfer pulse is generated. These sampling pulses a to n correspond to each picture element when one line of the video to be displayed is divided into 320 picture elements in the horizontal direction, and their positions are always constant with respect to the horizontal synchronizing signal H. controlled by.

These 320 sampling pulses a to n correspond to the 320 sample and hold circuit sets 31, respectively.
a to 31n, thereby providing one line to each sample and hold circuit set 31a to 32n.
When divided into 320 picture elements, the R, G, and B video signals of each picture element are individually sampled and held. The sampled and held 320 sets of R, G, and B video signals are stored in 320 sets of memories 32a to 32a after completion of sample and hold for one line.
32n all at once by a transfer pulse t,
Here, it is held for the next one horizontal scanning period.

One line of R, G, and B video signals held in the memories 32a to 32n are applied to 320 switching circuits 35a to 35n, respectively. The switching circuits 35a to 35n each have R, G,
B separate input terminals and a common output terminal for sequentially switching and outputting them, and the output of each switching circuit 35a to 35n is used as a control signal for modulating the electron beam to the electron beam flow control electrode 5 of the display element. are individually applied to each of the 320 conductive plates 15a to 15n. Each switching circuit 35a to 35n is a switching pulse generation circuit 3.
Switching is simultaneously controlled by switching pulses applied from 6 to 6. The switching pulse generation circuit 36 is controlled by the pulses r, g, and b from the horizontal driving pulse generation circuit 28, and the effective horizontal scanning period of each horizontal period is divided into three parts, and the switching pulse generation circuit 36 divides the effective horizontal scanning period of about 50 μsec into three, and performs switching every about 17 μsec. Circuits 35a to 35n
The R, G, and B video signals are time-divisionally output alternately and sequentially, and switching signals r, g, and b are generated to be supplied to the conductive plates 15a to 15n.

What should be noted here is that the switching circuit 3
The switching of the supply of R, G, and B video signals in 5a to 35n and the horizontal deflection of the horizontal deflection of the electron beam to the R, G, and B phosphor 20 by the horizontal deflection drive circuit 29 are performed in timing and order. They are also synchronously controlled so that they match perfectly. As a result, when the electron beam is irradiating the R phosphor, the irradiation amount of the electron beam is controlled by the R video signal, and G and B are similarly controlled, so that the R and G of each picture element are controlled in the same manner. , B phosphors are respectively controlled by the R, G, and B video signals of the picture elements, and each picture element is displayed by emitting light in accordance with the input video signal. This control is performed simultaneously on 320 picture elements for one line to display one line of video, and then
This is performed sequentially from the upper line for the 240 minute lines, and one image is displayed on the screen board 9.

The above operations are repeated for each field of the input television signal, and as a result,
A moving television image is projected on the screen board 9 in the same way as a normal television receiver.

As described above, television images are displayed on this display device.

Note that the terms "horizontal direction" and "vertical direction" in the above explanation refer to the horizontal direction, which is the direction in which line units are displayed when an image is projected, and the vertical direction, which is the direction in which the lines are stacked. It is used in this sense, and is not directly related to the vertical and horizontal directions on the actual screen.

Next, alignment positions in an embodiment of the present invention will be explained using FIGS. 4 to 6. Fourth
The figure is a longitudinal sectional view of the display device being adjusted by the alignment device, FIG. 5 is a sectional view taken along line A-A in FIG. 4, and FIG. 6 is an enlarged sectional view of the main part of FIG. 4 to 6, 37a is a container, 3
7b is a face container, 38 is an electrode block, 39
is a band for screws, 40a to 40d are terminals, 41a
-41c are embedded fixing pins, 42a-42c are springs, 43 is a bellows, 44 is a screw, 45 is a fluorescent surface, and 46 is a space within the bellows. The bellows 43 is made of a metal having substantially the same coefficient of expansion as the container 37a and the face container 37b, and is fixed to the container 37a so as to close the hole thereof.

In order to align the electrode block 38 of the flat image device with the fluorescent surface 45 coated on the face container 37b, a bellows 43 provided in close contact with the container 37a connects the inside of the container 37a and the face container 37b with the outside air. Completely separated, the screw 44 screwed into the screw band 39 pushes the inner surface of the bellows 43 to move the electrode block 38. The screw band 39 may not be formed into a band shape, but may be provided at four independent locations. Further, the bellows 43 is connected to the container 37.
It can be easily sealed by welding to a or using a low-temperature powder glass adhesive (frit). In this embodiment, alignment is performed using four adjustment mechanisms,
After completing the alignment, remove only the screw 44 or the screw band 39, and remove the inner space 46 of the bellows 43.
Fill it with resin adhesive etc. and fix it. In this embodiment, the amount of adjustment is 100 to 200 μm or less, and industrially, it is also possible to display an image, measure the position of the beam, and perform alignment using an automatic machine.

Effects of the Invention As explained above, according to the present invention, the following effects can be obtained.

Since positioning can be adjusted afterwards, the rate of defective products can be significantly reduced.

It is possible to reduce the processing of highly accurate parts for positioning.

It is possible to eliminate the need for a means to prevent positional displacement due to a difference in expansion coefficients when the temperature rises or a complicated structure.

[Brief explanation of the drawing]

FIG. 1 is an exploded perspective view showing the basic configuration of an image display element of an image display device as an example of a target for which the alignment device of the present invention is used, FIG. 2 is an enlarged view of the screen, and FIG. 3 is an enlarged view of the device. A block diagram showing the basic configuration of the drive circuit, FIG. 4 is a vertical cross-sectional view of an image display device being adjusted by an alignment device in an embodiment of the present invention, and FIG. 5 is taken along line A-A in FIG. 4. The sectional view, FIG. 6, is an enlarged view of the main part of FIG. 5. 37a... Container, 37b... Face container, 3
8...Electrode block, 39...Screw band, 4
0a to 40d...Terminal, 41a to 41c...Fixing embedded pin, 42a to 42c...Spring, 43...
...Bellows, 44...Screw, 45...Fluorescent material, 4
6...Space inside the bellows.

Claims (1)

[Claims] 1 Position in an image display device comprising a flat container with a phosphor screen formed on one surface thereof, and an electrode block that is housed inside the container and functions to irradiate the phosphor screen with an electron beam and draw a raster. The fitting device is provided with a plurality of bellows made of a metal whose expansion coefficient matches that of the material of the container, which are closely fixed to the container in a state of closing a plurality of holes provided in the container, and which are provided on the outer periphery of the container for screws. A band is provided, and a plurality of screws are screwed into the screw band in correspondence with holes in the container, and move the electrode block inside the container from outside the container via the bellows to align it with the phosphor screen. The positioning device is configured such that the bellows is filled with a resin adhesive to fix the electrode block after the electrode block is aligned with the screw.