JP5079982B2 - Field emission surface light source device and its cathode - Google Patents

Description

  The present invention relates to a field emission surface light source device, and more particularly to a field emission cathode.

  Surface light sources are widely used in many fields, particularly in the field of message displays. Many passive display technologies, including liquid crystal displays, require a surface light source that emits light uniformly in total to be an element. The prior art often obtains a plane that emits light uniformly by an optical method. For example, a liquid crystal back plate is formed by condensing a line light source onto a surface light source by an optical system.

  FIG. 1 shows a back light source 10 used in the liquid crystal display disclosed in Patent Document 1. The back light source 10 includes a light emitting diode 12, a light guide plate 14, and a microlens 16. The light guide plate 14 includes an incident surface (not shown) with respect to the light emitting diode 12, and the microlens 16 is positioned between the light emitting diode 12 and the incident surface of the light guide plate 14. Therefore, the uniform parallel light in which the diffused light from the diode 12 passes through the microlens 16 enters the light guide plate 14 from the incident surface and is guided. A uniform surface light source is formed by the action of the light plate 14.

  Moreover, the related art of the back light source using elements, such as a light-guide plate, is disclosed by patent document 2 and patent document 3. FIG.

  However, the surface light source element according to the above method cannot directly obtain the surface light source, and it is necessary to perform the following optical processing. In addition, a precision processing optical element is attached. For example, production costs such as microlenses and light guide plates are increased.

  In recent years, light source devices based on the field emission effect are sometimes manufactured. The main operating principle is as follows. When the potential of the cathode is lower than the anode or grid, there is an electric field from the surface of the cathode to the anode or grid, and if the strength of the electric field is appropriate, the cathode begins to emit electrons and the electrons It goes to the anode by the action, and the luminescent powder applied thereon is bombarded to emit light. Compared with the prior art, especially with a lamp tube, such an electric field light source only creates a vacuum between the cathode and the anode, and it is not necessary to introduce various gases, for example harmful gases such as mercury, and therefore Does not pollute the environment.

  Patent Document 4 discloses a light source element using a field emission cathode, and the field emission cathode includes a substrate and a plurality of emitters extended from the substrate. However, the light source device is a tubular device, which provides only a line light source and cannot provide a surface light source directly.

Therefore, there is a need to provide a field emission surface light source device that can directly provide a surface light source, and a cathode thereof.
Chinese Patent Application No. 0215111.5 Chinese Patent Application Publication No. 02107375.9 Chinese Patent Application No. 021288659.0 US Patent Publication No. 6,008,575

  An object of the present invention is to provide a field emission surface light source device capable of directly providing a surface light source and a cathode thereof so as to solve the problem that the surface light source of the prior art cannot be directly provided.

  For one of the objects of the present invention, the present invention provides a field emission surface light source device, which comprises a cathode having a plurality of emitters, the cathodes comprising a plurality of conductive support posts, the emitters comprising the emitters Distributed to conductive support pillars.

  The apparatus may include an anode relative to the cathode.

  The device may also include two anodes, the cathode being positioned between the two anodes.

  The emitter is formed on the surface of the conductive support column with respect to the anode. The emitter has an end, and the end should be oriented along and away from the surface normal to the conductive support column. The plurality of conductive support columns are selected to be columnar or columnar, and are distributed in parallel to each other on the same plane. A tensioning device is installed at at least one end of the at least one conductive support column. A grid is installed between the cathode and the anode.

  In another aspect of the present invention, the present invention provides a field emission cathode, which includes a substrate and a plurality of emitters formed on the substrate, the substrate comprising a plurality of mutually parallel conductive support posts. including. The emitter is distributed on the conductive support column.

  Compared with the prior art, in the present invention, the emitter is formed in the matrix of the cathode emitter in parallel with the distributed conductive support columns, and the electrons due to the electric field of the emitter emit light by impacting the light emitting layer of the anode, A surface light source can be provided directly without the need for optical processing with other optical elements.

  In addition, when the emitters are distributed along the normal of the surface of the conductive support column, the shielding effect between the emitters is greatly reduced, thus increasing the electron emission rate of the field emission cathode and improving the photoelectric conversion effect. In addition, the performance of the light source device can be improved. In addition, the present invention secures uniformity of electron emission and is more stable so that it is fixed to one end or both ends of the conductive support column using a tension device such as a spring. Is to increase.

  Next, detailed contents of the present invention will be described with reference to the drawings.

  Referring to FIGS. 2 to 4, the first embodiment of the present invention is a single-side field emission surface light source device 8. It includes a substrate 80, a cathode 81, and an anode 82. The substrate 80, the cathode 81, and the anode 82 are substantially parallel to each other, and are entirely packaged with glass and formed in a vacuum state.

  The apparatus 8 includes a plurality of glass columns 84 for maintaining the distance between the substrate 80 and the anode 82. A cathode fixing plate 89 for fixing the cathode 81 is installed on both sides of the substrate 80.

  The cathode 81 includes a plurality of conductive support columns 812 and an emitter (not shown). In order to reduce the shielding effect between the emitters, the conductive support pillars 812 are evenly distributed on the surface facing the anode 82, the end portions for emitting electrons are separated from the conductive support pillars 812, and It is better to distribute along the normal of the surface of the conductive support column 812. The plurality of conductive support columns 812 have a cylindrical shape and are arranged uniformly in parallel to the matrix of the cathode emitter at a certain distance. The conductive support pillars 812 should have the same shape and dimensions, and their central axes should be located in substantially the same plane. The cathode line 85 is positioned at one end of the cathode 81 and is bonded to one end of the plurality of conductive support columns 812.

The anode 82 is a glass plate having a transparent conductive film (not shown) and a light emitting layer 83 formed on the surface. The light emitting layer 83 has red, green, and yellow light emitting powders, and the light emitting powders are distributed in a strip shape parallel to the plurality of conductive support columns 812 of the cathode 81. Further, the light emitting layer 83 may include white light emitting powder that covers a part of the surface of the anode facing the cathode. An anode line 86 bonded to a transparent conductive film is installed at one end of the anode 82. It should be noted that the brightness of the device 8 is determined by the voltage of the anode 82, the current density, the luminous rate of the luminescent powder, and the like, and should be appropriately selected according to different usage conditions.

  An exhaust hole (not shown) is installed in one side wall of the apparatus 8 and an exhaust pipe 87 is bonded. A getter 88 for securing the degree of vacuum of the device 8 is installed on the inner wall of the exhaust pipe 87.

  In this embodiment, the conductive support column 812 has a thread-like structure. The emitter is formed on the surface of the conductive support column 812 by electrophoresis or chemical vapor deposition. The conductive support column 812 on which the emitter is formed is uniformly fixed in parallel to the cathode fixing plate 89 to form the cathode 81. Of course, after the cylindrical conductive support column 812 is fixed to the cathode fixing plate 89 in parallel, the emitter may be formed on the conductive support column 812 by the above method.

  Similarly, the emitter is small and includes a metal tip, a non-metal tip, a compound tip, and a one-dimensional nanomaterial. For example, a molybdenum tip, a silicon tip, a zinc oxide tip, etc. Nano-order tubular structures, rod-shaped structures, and linear structures, such as carbon nanotubes, silicon wires, molybdenum wires, and the like.

  Further, depending on the use situation, a lattice for improving the electron emission rate of the cathode 81 may be provided between the cathode 81 and the anode 82.

  Referring to FIGS. 5 to 7, the second embodiment of the present invention is a double-sided field emission surface light source device 9. The difference from the first embodiment is that the device 9 includes two anodes 90 and 92, and the cathode 91 is positioned between the anodes 90 and 92, and a plurality of conductive support pillars 912 constituting the cathode 91 are as follows. Form emitters (not shown) on the two surfaces beyond the anodes 90 and 92, respectively.

  In this embodiment, one end of the conductive support column 912 is fixed to a cathode fixing plate (not shown) by a spring 94 so that the conductive support column 912 is not easily bent and bent. The conductive support pillars 912 are stably fixed on the same plane. It is better to install springs 94 at both ends of the conductive support column 912 so as to increase the tensile effect.

  Other columnar structures can be selected as the conductive support columns, for example, square columns, regular pentagonal columns, or irregular multi-sided columns. The conductive support column may be pulled by replacing the spring with another element or device. Further, the number of conductive support pillars, the fixing method, and the distribution state of the cathode lines vary depending on the specific situation.

  In the present invention, emitters are formed in a matrix of cathode emitters in parallel with distributed conductive support columns, and electrons due to the electric field of the emitters emit light by impacting the light emitting layer of the anode, and are optically transmitted by other optical elements. A surface light source can be provided directly without the need for processing.

  In addition, when the emitters are distributed along the normal of the surface of the conductive support column, the shielding effect between the emitters is greatly reduced, thus increasing the electron emission rate of the field emission cathode and improving the photoelectric conversion effect. In addition, the performance of the light source device can be improved. In addition, the present invention secures the uniformity of electron emission by fixing the conductive support column to one or both ends of the conductive support column by using a tension device such as a spring and makes it more stable. Is to increase.

It is a schematic diagram of the surface light source device used for the liquid crystal display of a prior art. It is a three-dimensional schematic diagram of the single-sided field emission surface light source device of the present invention. It is a cross-sectional schematic diagram which follows the III-III line | wire of FIG. FIG. 4 is a schematic sectional view taken along line IV-IV in FIG. 2. It is a three-dimensional schematic diagram of the double-sided field emission surface light source device of the present invention. It is a cross-sectional schematic diagram which follows the VI-VI line of FIG. It is a cross-sectional schematic diagram which follows the VII-VII line of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 8 Single-sided field emission surface light source device 80 Substrate 81, 91 Cathode 812, 912 Conductive support pillar 82, 90, 92 Anode 83 Light emitting layer 84 Glass pillar 85 Cathode line 86 Anode line 87 Exhaust pipe 88 Getter 89 Cathode fixing plate 9 Both sides Field Emission Surface Light Source Device 94 Spring

Claims (5)

  A cathode having a plurality of emitters, two anodes facing the cathode, the cathode being positioned between the two anodes, the two anodes being transparent, and emitting light from the two anodes The cathode includes a plurality of conductive support columns, the emitter is formed on a surface of the conductive support column with respect to the anode, the emitter has an end portion, and the end portion is formed on the conductive support column. On the other hand, the field emission surface light source device is characterized by being directed along the surface normal and away. The field emission surface light source device according to claim 1, wherein the plurality of conductive support pillars are installed in parallel on the same plane. 3. The field emission surface light source device according to claim 1, wherein a metal, a nonmetal, a compound, or a one-dimensional nanomaterial is selected as the emitter material.   The field emission surface light source device according to any one of claims 1 to 3, wherein a tension device is installed at at least one end of the at least one conductive support column. The field emission surface light source device according to any one of claims 1 to 4 , wherein a columnar shape or a columnar shape is selected as the conductive support column.

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