JP2596308B2 - Image display device having field emission cathode and method of manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image display apparatus using a field emission cathode as an electron source.

[0002]

2. Description of the Related Art Conventionally, in an image display device (hereinafter referred to as FED) using a field emission cathode as an electron source, a distance between an anode substrate on which a display portion is formed and a cathode substrate on which a cathode is formed is kept constant. In order to do so, columns are provided between the substrates by various methods as exemplified in the following (1) and (2).

(1) A method of laminating frit glass This method is a method of forming pillars made of laminated frit glass while repeating screen printing and baking of a paste containing frit glass. Alternatively, a paste of a plurality of layers may be printed and fired collectively. Alternatively, there is a method in which a photosensitive glass paste is printed, formed into a predetermined shape by a photolithography method, and finally baked.

(2) Method of Using Photosensitive Resin A heat-resistant photosensitive resin such as polyimide is applied to a substrate by spraying or the like, exposed to a mask, and then developed to obtain a pillar having a desired shape.

[0005]

However, in these methods, a graphic display having a resolution similar to that of a CRT is used for the FE.
There are some problems when trying to obtain with D. Before pointing out the problem, the following general conditions required for the support are a to c. a. Exhaust efficiency is not reduced as much as possible. b. Low residual gas. c. When the pitch of the RGB phosphor layers provided on the display unit of the FED is set to, for example, 0.36 mm, the width of the phosphor layers is set to 100 μm so that the columns do not obstruct the display as much as possible. Therefore, the width of the surface where the support contacts the substrate is required to be 50 μm or less. However, in consideration of the withstand voltage performance between the cathode and the anode, the condition for spreading the electrons of the cathode, and the like, the height of the column needs to be about 0.1 mm to 0.3 mm. The arrangement position is limited between pixels.

The problem of the above-mentioned method (1) is that only a height of several tens of μm can be obtained at a time even if glass frit is screen-printed. That is, it must be laminated many times to obtain the required height for the column. Further, it is difficult to form a shape having a height larger than the width by laminating the frit. In addition, the method of laminating the frit makes it difficult to obtain a desired shape and the position accuracy is insufficient.

Furthermore, since it is necessary to perform firing, the upper surface of the support pillar is drooped, and it is difficult to make the height uniform. For this reason, some pillars do not serve as a support, and there is a problem that the withstand pressure is reduced.

[0008] Further, since the vehicle in the glass frit is released as gas during firing, irregularities remain on the surface of the column. Residual gas tends to adhere to these irregularities.

In the above-mentioned method (2), even if a light source having a good light source is used, since the film thickness is about 100 μm at a time, if the required height of the support is not more than that, the support must be stacked. Can not get the height of In addition, since an organic material is used, there is a problem of gas emission. In addition, in (1) and (2), photosensitive glass paste,
When the photosensitive resin is used as the pillar material, the phosphor layer must be formed after the pillar is formed on the substrate, and it is difficult to separately apply and form the phosphor layers.

The present invention has been made in view of the above-described problems of the conventional example, and has as its object to provide a column having a uniform height and a small amount of residual gas in a region between pixels of an FED.

[0011]

According to a first aspect of the present invention, there is provided an image display apparatus comprising: an anode substrate having a display portion having a phosphor layer; and a field emission cathode on an inner surface of the anode substrate facing the display portion. And a cathode substrate having an outer peripheral portion sealed at predetermined intervals by a sealing material, wherein the display portion is not provided between the inner surface of the anode substrate and the cathode substrate. A strut member made of fiber material is fixed.

According to a second aspect of the present invention, there is provided a method of manufacturing an image display device, comprising: forming a column member having a predetermined length from a fiber material; and providing a magnetic body at one end of the column member.
Holding the support member on a holding substrate provided with a magnet at a predetermined position, and connecting the other end of the support member to one of an anode substrate on which a display unit is formed or a cathode substrate on which a field emission cathode is formed. Positioning and fixing; positioning and fixing one end of the support member to the other of the anode substrate or the cathode substrate; and sealing the anode substrate and the cathode substrate with a sealing material and exhausting the inside. And a step of performing

According to a third aspect of the present invention, in the method of manufacturing an image display device, the support member is suctioned by the positioning means having the opening and the suction means communicating with the opening, and one end of the support member is sucked by the suction force. A step of positioning and holding the opening;
Positioning and fixing the other end of the support member held by the positioning means to one of an anode substrate on which a display unit is formed or a cathode substrate on which a field emission cathode is formed; and A step of positioning and fixing one end of the support member released from holding by the positioning means on the other side of the cathode substrate, and a step of sealing the anode substrate and the cathode substrate with a sealing material and exhausting the inside; have.

[0014]

Since the support member is made of fiber material, a support having a uniform height and a large height relative to the width can be obtained by a method such as cutting, and the distance between the anode substrate and the cathode substrate can be obtained without obstructing the display. Can be kept constant. In addition, since the surface is relatively smooth, gas adheres little during the manufacturing process.

[0015]

FIG. 1 is a sectional view of an image display apparatus according to an embodiment of the present invention. Anode substrate 10 having translucency and insulation
A light-transmitting anode conductor 101 is provided in a predetermined pattern on the inner surface of the “0”. The phosphor layer 102 is adhered to the anode conductor 101, and constitutes an anode as the display unit 103.

A field emission type cathode 1 as an electron source is provided on an inner surface of an insulating cathode substrate 104 facing the anode substrate 100.
05 is provided. A field emission cathode 105 is formed on a cathode conductor 106 provided on a cathode substrate 104, a gate electrode 108 provided on the cathode conductor 106 via an insulating layer 107, and formed on the gate electrode 108 and the insulating layer 107. And a cone-shaped emitter 110 provided on the cathode conductor 106 in the hole 109 formed.

The anode substrate 100 and the cathode substrate 104
A substantially columnar column member 111 is provided between them.
The support member 111 is a member obtained by cutting a glass fiber, which is an example of a fiber material, to a predetermined length.
03 and a region where the field emission cathode 105 does not exist. Both ends of the support member 111 are fixed to the substrates 100 and 104 by low softening point glass 112. Although only one support member 111 is shown in FIG. 1, the support between the substrates 100 and 104 is supported at many places. Then, the anode substrate 100 and the cathode substrate 1
The outer peripheral portion of 04 is sealed with a sealing material (not shown).

As in this embodiment, the glass fiber is FE
The following effects can be obtained by using the support member D. If a glass fiber having a predetermined width (diameter) is prepared, its height is determined by the length to be cut, so that it is easy to make the support member have a predetermined height. Therefore, it is possible to easily obtain a column member having a height higher than the width. By using such a support member, the distance between the anode substrate and the cathode substrate in the FED can be kept constant, and an FED with no variation in luminance and excellent withstand voltage performance can be obtained.

Further, since the width of the support member can be reduced to the minimum size that can withstand the pressure while obtaining the required height of the support member, a sufficient display area can be ensured and the FED of the FED can be secured. Exhaust efficiency when exhausting the inside during manufacturing is increased. In addition, since the support side is smooth,
Gas is less likely to adhere to the support itself during the manufacturing process.

Next, a description will be given of a method of aligning glass fibers as pillar members and incorporating the same into the FED. 1. Method using magnetic attraction force (see FIG. 2; note that the following numbers correspond to the drawing numbers) 1) An anode conductor 1 made of a transparent conductive film or the like and a low softening point Glass pattern 3, R, G, B
The phosphor layers 4 of three colors are formed at a predetermined pitch (for example, 360 μm pitch). Further, a sealing glass paste 5 is applied to the peripheral frame portion.

2) A glass fiber having a diameter of 50 μm is bundled into bundles of several thousands and hardened with resin, and sliced into a length of 200 μm. 3) Ni13 as a magnetic material is vacuum-deposited on one end of the sliced glass fiber 6.

4) The resin is dissolved in an organic solvent to take out the glass fiber 6 with Ni. 5) Pole arrangement pitch (for example, 360 μm
A jig incorporating the magnetic material 14 is prepared at (pitch), the glass substrate 7 is placed on the glass fiber 6 with the magnetic material 14 facing down, and the glass fiber 6 is held at the position of the magnetic material 14. I do.

6) In this state, the other end of the glass fiber 6 is applied to the glass substrate 12 previously coated with an ultraviolet curable adhesive 11 containing an inorganic substance to a thickness of several μm, and the adhesive 11 is applied. 7) The glass substrate 7 is removed by aligning with the anode substrate 2 and irradiating ultraviolet rays with the glass fiber 6 superimposed on the low softening point glass pattern 3 to cure the adhesive.

8) Thereafter, by firing at 400 to 500 ° C., the glass fiber 6 as a screen is made to have a low softening point glass due to an inorganic substance or its oxide contained in the adhesive after the adhesive is decomposed. In the state of being fixed on the pattern 3, the low softening point glass 3 is softened, then cooled and hardened to be fixed. In this way, a phosphor patterning substrate in which screens of φ50 μm and height of 200 μm are formed at a pitch of 360 μm is obtained.

Thereafter, a glass having a low softening point is adhered to the end of the glass fiber 6 to which Ni is adhered, and a cathode substrate 104 on which a field emission type cathode 105 is formed as shown in FIG. An image display device is obtained by sealing. According to the present manufacturing method, even if the fiber material has a large height relative to the diameter, the fiber material can be attached to the anode substrate or the cathode substrate at an accurate position. Further, in the present manufacturing method, a fiber material having a square cross section can also be applied.

2. Method using the suction force of the exhaust gas (see FIG. 3; note that the figure numbers and the section numbers in the following description)
Is compatible. ) A glass fiber having a diameter of 50 µm is bundled into a bundle of several thousands 20 and hardened with resin, and sliced into a length of 200 µm. Thereafter, the sliced glass fiber bundle 21 is immersed in an organic solvent, and the resin is melted to obtain a glass fiber 22.

The positioning means 23 of the glass fiber 22 used in this step has a box-shaped base 24. The inside of the base 24 is connected to a pump, which is a suction unit (not shown). In addition, openings 25 are formed on the upper surface of the base 24 at a pitch equal to the arrangement pitch of the glass fibers 22 serving as support members, and communicate with the inside of the base 24.
The diameter of the opening 25 is slightly larger than the diameter of the glass fiber 22. Then, the substrate 27 is
While sucking the inside, an appropriate amount of the glass fiber 22 is sprayed on the upper surface of the substrate, and the glass fiber 22 is sucked into the opening 25.
Fill and hold.

The transfer space 27 is uniformly applied to the glass plate 26. This is surface-transferred to the tip of the glass fiber 22 held by the positioning means 23. The transfer paste 27 has a low softening point glass as a main component, and is mixed with a resin or the like as needed to form an adhesive paste. The glass fiber 22 having a transfer paste at its tip is transferred to an anode substrate 28 on which an anode conductor, a phosphor layer and the like are formed in advance by the adhesive force of the transfer paste 27.

The fixing paste 30 is applied to the plate glass 29 in advance with a uniform thickness. Then, the fixing paste 30 is made to approach the anode substrate 28 with the glass fiber 22 facing upward, and the fixing paste 30 is brought into contact with one end of the glass fiber 22 to be adhered.

The glass fiber 22 is fixed to the anode substrate 28 by applying a sealing paste 31 for sealing around the anode substrate 28 and baking it at a predetermined temperature. Thereafter, although not shown, a cathode substrate on which a field emission cathode is formed is attached and hermetically sealed to obtain an image display device.

The diameter of the opening 25 may be increased with respect to the outside, and the diameter of the opening at the bottom may be equal to or slightly larger than the cross-sectional shape of the glass fiber 22. By doing so, the suction of the glass fiber 22 becomes easy. In the above description of the manufacturing process, an example in which the attachment of the anode substrate 28 to the glass fiber 22 and the attachment of the cathode substrate are performed in separate steps has been described. May be fired at once.

As described above, the strut member made of the fiber material has a very small width of several tens of μm, and it is difficult to form the pillar member vertically when the height is large with respect to the width. Can be easily formed.

Further, in the present manufacturing method, even if the support member is not of a cylindrical shape, for example, a spherical shape such as glass beads can be easily positioned by the positioning means 23. Further, the present manufacturing method has been described in the case where the cross section of the glass fiber 22 serving as the support member is circular.

[0034]

According to the image display device of the present invention, the dimensions of the plurality of support members can be set to be substantially the same by making the lengths at which the fiber material is cut uniform. For this reason, since the distance between the anode substrate and the cathode substrate can be kept constant in the FED, an excellent FED with uniform luminance and high withstand voltage performance can be obtained. Further, according to the method of manufacturing an image display device according to the present invention, the fiber material can be trimmed to a fixed length, and the cut fiber material can be reliably held and positioned on the substrate. For this reason, the excellent FED of the present invention as described above can be efficiently manufactured.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of an image display device according to an embodiment of the present invention.

FIG. 2 is a manufacturing process diagram showing one embodiment of the present invention.

FIG. 3 is a manufacturing process diagram showing another embodiment of the present invention.

[Explanation of symbols]

 2, 32, 100 Anode substrate 4, 102 Phosphor layer 6, 25 Glass fiber as fiber material 7 Glass substrate as holding substrate 13 Ni as magnetic material 14 Paste as magnet 26 Positioning means 28 Opening 103 Display 103 Cathode substrate 105 Field emission cathode

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yoshio Makita 629 Oshiba, Mobara-shi, Chiba Futaba Electronics Co., Ltd. (72) Inventor Satoshi Yoshimura 629 Oshiba, Mobara-shi, Chiba Futaba Electronics Co., Ltd.

Claims (3)

(57) [Claims] 1. An anode substrate provided with a display section having a phosphor layer, and a cathode substrate provided with a field emission cathode on an inner surface facing the display section of the anode substrate, are spaced apart from each other by a predetermined distance at an outer peripheral portion. An image display device sealed with a sealing material, wherein a support member made of a fiber material is fixed between an inner surface of the anode substrate on which the display unit is not provided and the cathode substrate. An image display device having an emission cathode. 2. A step of forming a column member having a predetermined length from a fiber material, a step of providing a magnetic body at one end of the column member, and holding the column member on a holding substrate provided with a magnet at a predetermined position. Process, one of the anode substrate on which the display unit is formed or the cathode substrate on which the field emission cathode is formed,
A step of positioning and fixing the other end of the support member, a step of positioning and fixing one end of the support member to the other of the anode substrate or the cathode substrate, and sealing the anode substrate and the cathode substrate with a sealing material. A method of manufacturing an image display device, comprising the steps of: sealing and exhausting the inside. 3. A step of sucking the support member by a positioning means having an opening and a suction means communicating with the opening, and positioning and holding one end of the support member in the opening by a suction force, and forming a display portion. Positioning and fixing the other end of the support member held by the positioning means to one of the formed anode substrate or the cathode substrate on which the field emission cathode is formed; and the other of the anode substrate or the cathode substrate An image display comprising: a step of positioning and fixing one end of the support member released from being held by the positioning means; and a step of sealing the anode substrate and the cathode substrate with a sealing material and exhausting the inside. Device manufacturing method.