JP2006093039A - Device of manufacturing image display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide the device of manufacturing an image display device enhancing reliability by preventing breakage of a spacer by suppressing thermal extension deformation and enhancing productivity by making quick heating treatment possible. <P>SOLUTION: The device of manufacturing the image display device is equipped with an upper heating source 30A faced to the spacer 8 being fit to a pattern surface formed on one side (a) of a back substrate at the prescribed intervals, and radiating heat rays to the pattern surface of the back substrate and the spacer, a lower heating source 30B faced to the other side (b) of the back substrate at the prescribed intervals and radiating the heat rays to the other side of the back substrate, and filter glass 40 interposed between the upper heating source and the spacer, selectively absorbing the wave length of the heat rays by utilizing the difference in spectral transmittance between the pattern surface of the back substrate and the spacer, transmitting the heat rays having the residual wave length and guiding to the back substrate and the spacer. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a manufacturing apparatus that manufactures an image display device including an envelope having a rear substrate and a front substrate that are arranged to face each other and a spacer interposed therebetween.

In recent years, flat image display devices have attracted attention as image display devices because of efficient space utilization or design factors. Among them, an electron emission type image display device such as a field emission device (hereinafter referred to as FED) is expected to be an excellent display because of merits such as high luminance, high resolution, and low power consumption.
As one type of FED, for example, as disclosed in [Patent Document 1], development of a display device (hereinafter, referred to as SED) including an electron-emitting device which is a surface conduction type display device is advanced. ing.

The SED has a front substrate and a rear substrate that are opposed to each other with a predetermined gap. These substrates are joined to each other at peripheral edges via a rectangular frame-shaped side wall, and the inside is evacuated to form a flat envelope having a flat panel structure.
A phosphor layer of three colors is formed on the inner surface of the front substrate, and on the inner surface of the rear substrate, a large number of electron-emitting devices corresponding to each pixel are arranged as an electron emission source for exciting and emitting the phosphor layer. ing. A large number of wires for driving the electron-emitting devices are provided in a matrix on the inner surface of the rear substrate, and the end portions are drawn out of the vacuum envelope.
JP-A-9-82245

In manufacturing the SED, the peripheral edge portion of the back substrate on which the electron-emitting devices are formed and the rectangular frame-shaped side wall are joined in the air via a low-melting glass adhesive called frit glass. Further, a plurality of spacers are sealed on the back substrate with a low-melting glass material in the atmosphere. Thereafter, the back substrate and the front substrate are subjected to a so-called baking process in which a gas adsorbed on the surface of each member is sufficiently released, in a vacuum atmosphere, and then a cooling process is performed.
Further, a getter film is deposited on the phosphor screen of the front substrate, and then the rear substrate and the front substrate are heated to melt the indium filled in the respective sealing surfaces. The back substrate and the front substrate are joined through the side wall, and after pressurizing with a predetermined pressure, the indium is removed and solidified to seal the back substrate and the front substrate through the side wall.
By the way, the problem is that when the spacer is attached to the back substrate and baking is performed, the thermal expansion deformation of the spacer with respect to the back substrate is surely suppressed and the spacer is prevented from being broken, thereby improving the reliability. Need to get. That is, in this baking process, in order to shorten the processing time and increase the productivity, the rear substrate and the spacer are rapidly heated using a lamp heater as a heating source.

However, the individual spacers are attached to the rear substrate in the form of radiating fins, and the thermal capacity of the spacer is extremely smaller than the thermal capacity of the rear substrate. Due to the difference in heat capacity, when the rapid heating process is performed, the spacers are heated to a temperature higher than that of the rear substrate, and are extended more than the rear substrate.
As described above, the temperature difference between the back substrate and the spacer is large, and the extension degree of the spacer is large. Therefore, the spacer may damage the pattern surface of the back substrate or the electron-emitting device, and may damage the spacer itself. . It is possible to stop the rapid heating and perform a baking process over time, but this time the productivity is lowered.

  The present invention has been made paying attention to the above circumstances, the purpose of which is to suppress the thermal expansion deformation of the spacer with respect to the back substrate when baking is performed after joining the spacer to the back substrate, An object of the present invention is to provide an apparatus for manufacturing an image display device which can prevent breakage of a spacer, improve reliability, and enable rapid heating treatment to improve productivity.

In order to satisfy the above-described object, the present invention supports a back substrate and a front substrate which are arranged opposite to each other, and an atmospheric pressure load which is interposed between the back substrate and the front substrate and acts from outside the back substrate and the front substrate. In addition, the image display device includes an envelope having a spacer that holds a distance between the substrates at a predetermined value, and is attached to the pattern surface side of the rear substrate and the rear substrate on which the pattern surface is formed on one surface side. In the manufacturing apparatus of the image display device that performs the heat treatment on the spacer,
A first heating source disposed opposite to the spacer on the pattern surface side of the rear substrate with a predetermined interval and radiating heat rays to the pattern surface of the rear substrate and the spacer, and a predetermined interval on the other surface side of the rear substrate. And a second heating source that radiates heat rays to the other surface of the back substrate disposed oppositely, and a spectral transmittance characteristic between the pattern surface of the back substrate and the spacer interposed between the first heating source and the spacer. The filter includes a filter that selectively absorbs the wavelength of the heat rays by utilizing the difference and transmits the heat rays of the remaining wavelengths to the back substrate and the spacer.

Furthermore, the present invention supports a back substrate and a front substrate that are arranged opposite to each other, and supports an atmospheric pressure load that is interposed between the back substrate and the front substrate and acts from the outside of the back substrate and the front substrate, and a distance between the substrates. An image display device including an envelope having a spacer for holding the substrate at a predetermined value, and a heat treatment for a back substrate having a pattern surface formed on one surface side and a spacer attached to the pattern surface side of the back substrate In the image display device manufacturing apparatus
A first heating source disposed opposite to the spacer on the pattern surface side of the rear substrate with a predetermined interval and radiating heat rays to the pattern surface of the rear substrate and the spacer, and a predetermined interval on the other surface side of the rear substrate. And a second heating source that radiates heat rays to the other surface of the rear substrate, the first heating source having a spectral transmittance characteristic that matches the spectral transmittance characteristic of the pattern surface of the rear substrate. Only emit heat rays of wavelength.

  According to the present invention, the thermal expansion deformation of the spacer with respect to the back substrate can be suppressed, the fracture of the spacer can be prevented, the reliability can be improved, the rapid heating process can be performed, and the productivity can be improved. There is an effect.

Hereinafter, embodiments applied to a process of manufacturing a flat-type image display device according to the present invention will be described in detail with reference to the drawings.
First, an SED (Surface-conduction Electron-emitter Display) will be described as an example of a flat-type image display device with reference to FIGS.
FIG. 1 is a perspective view showing a vacuum envelope (hereinafter also referred to as a display panel) 10 of an SED in a state where a front substrate 2 is partially cut away. FIG. FIG. 3 is a cross-sectional view of the envelope 10 taken along line II-II, and FIG. 3 is a partially enlarged cross-sectional view in which the cross section of FIG. 2 is partially enlarged.

As shown in FIGS. 1 to 3, the display panel 10 includes a front substrate 2 and a rear substrate 4 each made of a rectangular glass plate, and these substrates are separated from each other with a gap of about 1.0 to 2.0 mm. Opposed in parallel. The back substrate 4 has a size one size larger than the front substrate 2. The front substrate 2 and the back substrate 4 are joined together via a rectangular frame-shaped side wall 6 made of a glass material, and constitute a vacuum envelope having a flat flat panel structure in which the inside is a vacuum.
A phosphor screen 12 that functions as an image display surface is formed on the inner surface of the front substrate 2. The phosphor screen 12 is configured by arranging red, blue, and green phosphor layers R, G, and B and a light shielding layer 11, and these phosphor layers are formed in stripes or dots. A metal back 14 made of aluminum or the like is formed on the phosphor screen 12.

On the inner surface of the back substrate 4, a number of surface conduction type display elements each emitting an electron beam as an electron emission source that emits electrons for exciting and emitting the phosphor layers R, G, and B of the phosphor screen 12. The electron-emitting device 16 is provided. These electron-emitting devices 16 are arranged in a plurality of columns and a plurality of rows corresponding to each pixel, that is, for each of the phosphor layers R, G, and B.
Each electron-emitting device 16 includes an electron emitting portion (not shown) and a pair of device electrodes for applying a voltage to the electron emitting portion. Further, on the inner surface of the back substrate 4, a large number of wirings 18 for applying a driving voltage to the respective electron-emitting devices 16 are provided in a matrix shape, and end portions thereof are drawn out of the vacuum envelope 10. Yes.

The side wall 6 functioning as a bonding member is sealed to the peripheral edge of the front substrate 2 and the peripheral edge of the back substrate 4 by a sealing material 20 such as a low melting glass material or a low melting metal material, for example. Are joined. Here, the back substrate 4 and the side wall 6 are bonded to each other using frit glass 20a, and the front substrate 2 and the side wall 6 are bonded to each other using indium 20b. When sealing the back substrate 4 and the side wall 6 with the wiring 18 with a low melting point metal material, it is necessary to provide an insulating layer as an intermediate layer in order to avoid an electrical short between the wiring 18 and the sealing material 20.
The display panel 10 includes a plurality of elongated plate-like spacers 8 made of glass between the front substrate 2 and the rear substrate 4. In the present embodiment, the spacer 8 is a plurality of elongated glass plates, but a grid (not shown) made of a rectangular plate-like metal plate, and a large number of columnar pillars integrally provided on both sides of the grid. You may comprise with a spacer (not shown).

Each spacer 8 is placed on the metal back 14 and the upper end 8 a that contacts the inner surface of the front substrate 2 through the light shielding layer 11 of the phosphor screen 12 and the wiring 18 provided on the inner surface of the rear substrate 4. It has a lower end 8b in contact therewith. The plurality of spacers 8 support an atmospheric pressure load acting from the outside of the front substrate 2 and the back substrate 4 and maintain the distance between the substrates at a predetermined value.
Further, the SED includes a voltage supply unit (not shown) that applies an anode voltage between the metal back 14 of the front substrate 2 and the rear substrate 4. For example, the voltage supply unit applies an anode voltage between the two so that the potential of the back substrate 4 is set to 0 V and the potential of the metal back 14 is set to about 10 kV.

In the SED, when an image is displayed, a voltage is applied between the device electrodes of the electron-emitting device 16 via a drive circuit (not shown) connected to the wiring 18, and an electron beam is emitted from the electron-emitting portion of any electron-emitting device. While discharging, an anode voltage is applied to the metal back 14. The electron beam emitted from the electron emitting portion is accelerated by the anode voltage and collides with the phosphor screen 12. Thereby, the phosphor layers R, G, and B of the phosphor screen 12 are excited to emit light, and a color image is displayed.
In manufacturing such SED, the side wall 6 is joined to the back substrate 4 through a low-melting glass adhesive called frit glass 20a. In this state, the back substrate 4 is processed with the electron-emitting devices 16 and the wirings 18, and the phosphor screen 12 and the metal back 14 are formed on the front substrate 2.

The back substrate 4 to which the spacers 8 are attached and the front substrate 2 are sent to a vacuum atmosphere chamber and are baked as described later. That is, when the chamber reaches a high degree of vacuum of about 10 ⁻⁵ Pa, the back substrate and the front substrate are baked to a temperature of about 300 ° C., and the surface adsorption gas of each of the substrates 4 and 2 is sufficiently released.
Next, after the back substrate 4 and the front substrate 2 are cooled to a temperature of about 100 ° C., for example, a getter film is deposited on the back substrate 4 and the front substrate 2, and the getter film is formed on the phosphor screen 12 and the metal back 14. A Ba film as a film is formed by vapor deposition. The Ba film is prevented from being contaminated with oxygen, carbon, or the like, and can maintain an active state. Then, the back substrate 4 and the front substrate 2 are sent to a chamber in a vacuum atmosphere, and the back substrate 4 and the front substrate 2 are sealed through the side wall 6 in the vacuum atmosphere.

Hereinafter, the baking process with respect to the back substrate 4 and the spacer 8 attached to the one surface side a which is this inner surface is demonstrated.
FIG. 4 schematically shows the state of the baking process.
A baking chamber (not shown) that is in a vacuum atmosphere is opposed to the upper and lower sides with a predetermined interval, and is parallel to each other, an upper heating source 30A that is a first heating source and a lower heating that is a second heating source. A source 30B is arranged. Both the upper heating source 30A and the lower heating source 30B have their heating surfaces K facing each other.
Between the heating surfaces K of the upper heating source 30A and the lower heating source 30B, the back substrate 4 to which the spacer 8 is attached is disposed on one surface side (inner surface) a. Actually, the spacer 8 is on the upper surface side of the back substrate 4, and a filter glass 40 described later is interposed between the spacer 8 and the upper heating source 30 </ b> A. Further, there is no member to be attached to the other surface side b of the back substrate 4, and the lower heating source 30 </ b> B is disposed on the other surface side b of the back substrate 4 with a predetermined interval.

The filter glass 40 is attached to the back substrate and the electron emission element 16 provided on one surface side a of the back substrate 4, a pattern surface including a plurality of wirings 18 for applying a driving voltage to each electron emission device. The wavelength of the heat rays is selectively absorbed using the difference in spectral transmittance characteristics with the spacer 8, the heat rays of the remaining wavelengths are transmitted, and the heat rays irradiated from the first heating source 30 </ b> A are transmitted to the rear substrate 4. It serves to guide the spacer 8.
In other words, the first heating source 30A and the second heating source 30B are halogen lamp heaters having a peak wavelength on the visible light side, and the spectral transmittance characteristics of the filter glass 40 are the same as those of the spacer 8. Spectral transmittance characteristics. Therefore, the heat rays from the halogen lamp heater 30 </ b> A in the wavelength region that passes through the filter glass 40 are not absorbed by the spacer 8, but heat the back substrate 4.

Specifically, by turning on the halogen lamp heater 30 </ b> A, light in the entire range from far infrared light to visible light and near infrared light irradiates the filter glass 40. On the other hand, the spacer 8 has a spectral transmittance characteristic that absorbs far-infrared light and transmits visible light and near-infrared light.
Since the filter glass 40 also has the same spectral transmittance characteristics as the spacer 8, it absorbs far infrared light and transmits visible light and near infrared light. On the other hand, a pattern surface is provided on one surface side a which is a mounting surface of the spacer 8 of the back substrate 4 and is formed to have a characteristic of absorbing visible light and near infrared light efficiently.

A baking process is performed under such conditions.
As described above, the rear substrate 4 having the spacer 8 attached to the one surface side a is disposed between the upper heating source 30A and the lower heating source 30B, which are halogen lamp heaters, facing each other at a predetermined interval. After the filter glass 40 is interposed between the spacer 8 and the upper heating source 30B, heat rays are irradiated from the upper heating source 30A and the lower heating source 30B.
All the heat rays radiated from the lower heating source 30B are directly guided to the lower surface of the back substrate 4 and irradiated to heat the lower surface of the back substrate 4 as indicated by double large arrows in the figure. The heat rays radiated from the upper heating source 30A are visible light and near-infrared light indicated by large arrows in the figure, and far-infrared light indicated by hatched arrows in the figure, all of which irradiate the filter glass 40.

As described above, since the filter glass 40 has the same spectral transmittance characteristic as that of the spacer 8, the filter glass 40 is heated by absorbing far-infrared light and rises in temperature. On the other hand, visible light and near infrared light are transmitted, and the transmitted light irradiates the back substrate 4 and the spacer 8.
Although the spacer 8 absorbs far-infrared light in terms of characteristics, it does not absorb visible light and near-infrared light and is not heated. On the other hand, the pattern surface formed on the back substrate 4 has a characteristic of absorbing visible light and near infrared light, and thus is efficiently heated.
The back substrate 4 is also heated from the other side b by the lower heating source 30B, and in addition to this, the back substrate 4 is also heated from the upper heating source 30A by visible light and near-infrared light that are heat rays that have passed through the filter glass 40. The device itself is heated rapidly, and the temperature rises quickly.

Further, the filter glass 40 absorbs only far-infrared light and has a certain temperature rise, from which radiant heat is released as indicated by solid arrows. The spacer 8 is heated by a secondary radiant heat ray, which is radiant heat from the filter glass 40, and the temperature rises. Furthermore, since the spacer 8 is attached to the back substrate 4, a certain amount of heat is transferred to the spacer 8 by heating the back substrate 4.
Although the heat capacity of the spacer 8 is smaller than the heat capacity of the back substrate 4, the amount of heat received by the spacer 8 is smaller than the amount of heat received by the back substrate 4. The heating temperature for 4 rises to almost the same temperature.
Therefore, by using the same heat source, a large amount of heat energy is input to the back substrate 4 having a large heat capacity, and the energy absorbed by the spacer 8 having a small heat capacity is reduced. The temperature difference is reduced, so that the extension amount of the spacer 8 relative to the back substrate 4 can be small, and the back substrate 4 can be rapidly heated in a short time without damaging the spacer.

The surface of the spacer 8 attached to the back substrate 4 is coated with a conductive film from such a condition as not to change the trajectory of electrons emitted from the electron emitters 16 attached to the pattern surface of the back substrate. Yes. The spacer 8 made of a colorless and transparent glass material is formed in reddish brown by conducting a conductive film coating.
Therefore, if the filter glass 40 is processed so that reddish brown light is transmitted in the visible light region of the spectral transmittance characteristics of the glass, the effects described above can be obtained. That is, the filter glass 40 may be formed on the surface thereof with the same conductive film as that formed on the surface of the spacer 8.
Further, by forming a band-pass dichroic filter on the surface of the filter glass 40 that transmits a large wavelength region of 0.7 μm in the visible light region, the above-described effects can be obtained.

A baking process as schematically shown in FIG. 5 may be performed.
The baking chamber (not shown) in a vacuum atmosphere is opposed to the upper and lower sides with a predetermined interval, and is parallel to each other, the upper heating source 30C as the first heating source and the lower heating as the second heating source. A source 30B is arranged. Both the upper heating source 30C and the lower heating source 30B have their heating surfaces K facing each other.
Between the heating surfaces K of the upper heating source 30C and the lower heating source 30B, the back substrate 4 to which the spacer 8 is attached on one surface side a is disposed. Here, a spacer 8 is attached to the upper surface side of the back substrate 4. Further, there is no member to be attached to the other surface side b of the back substrate 4, and the lower heating source 30 </ b> B is disposed on the other surface side of the back substrate 4 with a predetermined interval.

In other words, the upper heating source 30C and the lower heating source 30B are halogen lamp heaters having a peak wavelength on the visible light side. In particular, the halogen lamp heater, which is the lower heating source 30B, generates heat to irradiate the back substrate 4 with light in the entire range from far infrared light to visible light and near infrared light.
On the other hand, the halogen lamp heater which is the upper heating source 30C has a spectral transmittance characteristic equivalent to that of the spacer 8 in the wavelength characteristic, and the heat rays irradiated from this heater are not absorbed by the spacer, and the rear substrate 4 Heat.
Specifically, by turning on the upper heating source 30 </ b> C, visible light and near infrared light, excluding far infrared light, irradiate the back substrate 4 and the spacer 8. On the other hand, the spacer 8 has a spectral transmittance characteristic that absorbs far-infrared light and transmits visible light and near-infrared light. On the other hand, the pattern surface formed on one surface side a which is the mounting surface of the spacer 8 of the back substrate 4 is formed to have a characteristic of efficiently absorbing visible light and near infrared light.

A baking process is performed under such conditions.
As described above, the rear substrate 4 having the spacer 8 attached to the one surface side a is disposed between the upper heating source 30C and the lower heating source 30B, which are halogen lamp heaters, facing each other at a predetermined interval. Then, heat rays are irradiated from the upper heating source 30C and the lower heating source 30B.
All the heat rays radiated from the lower heating source 30B are directly guided to the lower surface of the back substrate 4 and irradiated to heat the lower surface of the back substrate 4 as indicated by double large arrows in the figure. The heat rays radiated from the upper heating source 30C are visible light and near-infrared light indicated by hatched arrows in the figure, all of which irradiate the back substrate 4 and the spacer 8.

As described above, the upper heating source 30C has a spectral transmittance characteristic equivalent to that of the spacer 8, and does not emit far-infrared light but emits visible light and near-infrared light. The spacer 8 absorbs far-infrared light but does not absorb visible light and near-infrared light, so that heating by the upper heating source 30C is not performed. On the other hand, since the pattern surface formed on the one surface side a of the back substrate 4 has a characteristic of absorbing visible light and near infrared light, it is efficiently heated.
Further, the back substrate 4 is heated from the other side b by the lower heating source 30B, and in addition to this, the upper substrate 30C is also heated by visible light and near infrared light, so that the back substrate 4 itself is rapidly heated. The temperature rises quickly. A certain amount of heat is transferred to the spacer 8 by heating the back substrate 4.

Although the heat capacity of the spacer 8 is formed smaller than the heat capacity of the back substrate 4, the amount of heat received by the spacer 8 is smaller than the amount of heat received by the back substrate 4. The heating temperature for 4 rises to almost the same temperature.
Accordingly, a large amount of heat energy is input to the back substrate 4 having a large heat capacity, and the energy absorbed by the spacer having a small heat capacity is reduced, thereby reducing the temperature difference between the back substrate 4 and the spacer 8. The extension amount of the spacer 8 relative to the back substrate 4 can be small, and the back substrate 4 can be rapidly heated in a short time without damaging the spacer.

The external appearance perspective view which shows the vacuum envelope of SED based on embodiment in this invention. The cross-sectional perspective view which cut | disconnected the vacuum envelope of FIG. 1 along line II-II based on the embodiment. The partial expanded sectional view which expands and shows the cross section of FIG. 2 based on the embodiment partially. The schematic diagram explaining the baking process of the embodiment. The schematic diagram explaining the baking process of different embodiment.

Explanation of symbols

  4 ... back substrate, 2 ... front substrate, 8 ... spacer, 30A ... upper heating source (first heating source), 30B ... lower heating source (second heating source), 40 ... filter glass.

Claims (4)

The rear substrate and the front substrate, which are arranged opposite to each other, are interposed between the rear substrate and the front substrate, support the atmospheric pressure load acting from the outside of the rear substrate and the front substrate, and the predetermined distance between the substrates. An image display device comprising an envelope having a spacer to be held in
In the manufacturing apparatus of the image display device in which the back substrate having the pattern surface formed on one surface side and the spacer attached to the pattern surface side of the back substrate are heated.
On the pattern surface side of the back substrate, a first heating source that is disposed to face the spacer with a predetermined interval and emits heat rays to the pattern surface of the back substrate and the spacer;
A second heating source disposed opposite to the other surface side of the rear substrate with a predetermined interval and radiating heat rays to the other surface of the rear substrate;
It is interposed between the first heating source and the spacer, selectively absorbs the wavelength of the heat ray using the difference in spectral transmittance characteristics between the pattern surface of the back substrate and the spacer, and the heat ray of the remaining wavelength And an image display device manufacturing apparatus, comprising: a back substrate and a filter that transmits the light to the spacer. As the first heating source, a halogen lamp heater having a peak wavelength on the visible light side is used,
2. The apparatus for manufacturing an image display device according to claim 1, wherein the filter has a spectral transmittance characteristic equivalent to a spectral transmittance characteristic of the spacer.   2. The apparatus for manufacturing an image display device according to claim 1, wherein the filter is formed on the surface thereof with the same conductive film as the conductive film formed on the surface of the spacer. The rear substrate and the front substrate, which are arranged opposite to each other, are interposed between the rear substrate and the front substrate, support the atmospheric pressure load acting from the outside of the rear substrate and the front substrate, and the predetermined distance between the substrates. An image display device comprising an envelope having a spacer to be held in
In the manufacturing apparatus of the image display device in which the back substrate having the pattern surface formed on one surface side and the spacer attached to the pattern surface side of the back substrate are heated.
On the pattern surface side of the back substrate, a first heating source that is disposed to face the spacer with a predetermined interval and emits heat rays to the pattern surface of the back substrate and the spacer;
A second heating source disposed opposite to the other surface side of the rear substrate with a predetermined interval and radiating heat rays to the other surface of the rear substrate;
The apparatus for manufacturing an image display device, wherein the first heating source emits only heat rays having a wavelength having a spectral transmittance characteristic that matches the spectral transmittance characteristic of the pattern surface of the rear substrate.

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