JP2007026999A - Display device and method for manufaturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a display device which can be manufactured with relative ease at low cost and can improve a yield, and a method for manufacturing the display device. <P>SOLUTION: An SED comprises a front substrate 2 having a phosphor screen and a metal back, a rear substrate having a plurality of electron emitting elements, an interlock spacer 8 placed between the front substrate 2 and the rear substrate, and a side wall to seal the periphery of the substrates. The interlock spacer 8 has a structure which couples a plurality of pillar spacers 8a with a metal wire 8b flat and beltlike, where both ends of the pillar spacers 8a are attached to the inner surfaces of the respective substrates. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a display device that displays a color image by emitting electrons from an electron-emitting device provided on a rear substrate and exciting and emitting a phosphor layer provided on the front substrate, and a method for manufacturing the display device.

  In recent years, a liquid crystal display, a field emission display (FED), a plasma display (PDP), etc. are known as a display device having a vacuum envelope having a flat flat panel structure. In addition, as a kind of FED, a display device (hereinafter referred to as SED) including a surface conduction electron-emitting device has been developed.

  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 rectangular frame-shaped side walls, 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.

  A plate-like grid is disposed between the front substrate and the rear substrate. In this grid, a plurality of beam passage holes are formed in a positional relationship aligned with the electron-emitting devices, and a plurality of holes for maintaining a gap between the substrates by contacting the inner surfaces of the front substrate and the rear substrate. Columnar spacers are provided (see, for example, Patent Document 1).

  When operating this SED, a high voltage of about 10 [kV] is applied between the substrates, and a drive voltage is selectively applied to each electron-emitting device via a drive circuit connected to the wiring. Thereby, an electron beam is selectively emitted from each electron-emitting device, and these electron beams are irradiated to the corresponding phosphor layer through the corresponding beam passage hole of the grid, and the phosphor layer is excited and emitted. An image is displayed.

  As described above, when a spacer grid in which a plurality of spacers are attached to the grid is adopted, all the spacers can be positioned and attached to the grid with high accuracy, and productivity can be improved, but manufacturing is difficult. Since the yield is low and the grid is relatively expensive, there is a problem that the manufacturing cost is high. Also, even if all the spacers are positioned with high accuracy and attached to the grid, if the grid is distorted for some reason, the contact height of the spacers to the substrate becomes non-uniform, and the spacer grid is placed between the substrates. When it arrange | positions to, the problem that a strong stress acts on a specific spacer and it destroys will arise.

For this reason, a method of positioning and mounting a plurality of columnar spacers one by one without using a grid is also conceivable, but the assembly takes a lot of time, and there is a problem that the manufacturing cost increases. In order to shorten the assembly time, a method of forming the spacer in a strip shape instead of a column shape is conceivable. However, it is difficult to uniformly control the height of the strip spacer along its longitudinal direction, which causes a problem of a decrease in yield. Further, since the strip spacer is formed of a thin and long strip glass, there is a problem that handling becomes difficult as the panel becomes larger.
JP 2003-31818 A

  The present invention has been made in view of the above points, and an object of the present invention is to provide a display device that can be manufactured relatively easily and inexpensively and can increase the yield, and a method for manufacturing the display device.

  In order to achieve the above object, a display device according to the present invention includes a first substrate having a phosphor layer, a second substrate having excitation means for exciting the phosphor layer, and a contact between the first and second substrates. A plurality of columnar spacers whose both ends are in contact with the first and second substrates, and the plurality of columnar spacers are aligned in parallel with each other. And a connecting member connected side by side.

  Further, the method for manufacturing a display device according to the present invention includes a step of preparing a first substrate having a phosphor layer and a second substrate having an excitation means for exciting the phosphor layer, a plurality of columnar spacers, and these A step of preparing a spacer structure having a connecting member in which a plurality of columnar spacers are arranged in parallel and connected to each other; and holding the both ends of the connecting member and positioning the spacer structure on the first substrate. Fixing one end of each of the columnar spacers to the first substrate, and causing the second substrate to face the first substrate having the spacer structure so that the excitation means faces the phosphor layer, A step of bringing the second substrate into contact with the other ends of the plurality of columnar spacers and sealing the peripheral portions of both substrates.

  According to the above invention, a plurality of columnar spacers arranged in a row can be connected together by the connecting member and handled together, and it is not necessary to attach the columnar spacers to the substrate one by one, thereby improving productivity. Further, the contact height of the connected plurality of columnar spacers with respect to the substrate can be made uniform, the columnar spacers can be prevented from being broken, and the yield can be improved.

  Since the display device of the present invention has the configuration and operation as described above, it can be manufactured relatively easily and inexpensively and the yield can be increased.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
First, an SED (Surface-conduction Electron-emitter Display) 1 will be described as an example of a display device according to an embodiment of the present invention with reference to FIGS. FIG. 1 is a perspective view showing the vacuum envelope 10 of the SED 1 with the front substrate 2 partially cut away. FIG. 2 shows the vacuum envelope 10 of FIG. 1 at the position of line II-II. FIG. 3 is a partially enlarged sectional view in which the section of FIG. 2 is partially enlarged.

  As shown in FIGS. 1 to 3, the SED 1 includes a front substrate 2 (first substrate) and a rear substrate 4 (second substrate) each made of a rectangular glass plate, and these substrates are about 1.0-2. They are arranged opposite to each other in parallel with a gap of 0 mm. The back substrate 4 has a size one size larger than the front substrate 2. Further, the front substrate 2 and the rear substrate 4 are joined to each other through a rectangular frame-shaped side wall 6 made of glass, and constitute a vacuum envelope 10 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. On the phosphor screen 12, a metal back 14 made of an aluminum thin film or the like is formed.

  On the inner surface of the back substrate 4, a number of surface-conduction type electron emitters 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. An element 16 (excitation means) 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, for example, a sealing material 20 such as low melting glass or low melting metal, and these substrates are bonded to each other. is doing. In the present embodiment, the back substrate 4 and the side wall 6 are joined using frit glass 20a, and the front substrate 2 and the side wall 6 are joined using indium 20b. If the back substrate 4 with the wiring 18 and the side wall 6 are sealed with a low melting point metal, 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 SED 1 includes a plurality of sets of connecting spacers 8 that function as the spacer structure of the present invention between the front substrate 2 and the rear substrate 4. Each set of connecting spacers 8 has a structure in which a plurality of long and thin cylindrical spacers 8a (columnar spacers) made of glass are arranged in a row in parallel with each other and connected by a flat strip-shaped metal wire 8b (connecting member). Have. The plurality of sets of connecting spacers 8 are attached substantially parallel to each other in the short side direction of the vacuum envelope 10 in a posture in which the metal wires 8 b extend in the long side direction of the vacuum envelope 10.

  Each columnar spacer 8a is placed on the metal back 14 and the upper end contacting the inner surface of the front substrate 2 via 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 in contact with it, supports an atmospheric pressure load acting from the outside of the front substrate 2 and the back substrate 4, and functions to maintain a predetermined interval between the substrates.

  Further, the SED 1 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 1, when displaying an image, a voltage is applied between the element electrodes of the electron-emitting device 16 through 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 16. And 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.

Here, the manufacturing method of the spacer structure 8 described above will be described with reference to FIGS.
First, two molds 31 and 32 as shown in a simplified manner in FIG. 4 are prepared. A recess 33 as shown in FIG. 5 is formed on the inner surface 31 a where one mold 31 faces the other mold 32. The recess 33 is formed by overlapping a plurality of semi-cylindrical recesses 33a divided into two in the axial direction to form a columnar columnar spacer 8a and a band-shaped recess 33b for disposing a band-shaped metal wire 8b. Is formed. The plurality of semi-cylindrical recesses 33a are arranged in parallel with a predetermined distance from each other, and a belt-like recess 33b passes through the center thereof. A recess 33 having the same shape is also formed on the inner surface 32a of the other mold 32.

  Next, as shown in FIG. 4, glass paste 81 (or ceramic paste) is filled in the plurality of semi-cylindrical recesses 33a of the two molds 31 and 32, and the metal wire 8b is set in the strip-shaped recess 33b. The metal wire 8b may be formed of a material having substantially the same thermal expansion coefficient as that of the front substrate 2 and the rear substrate 4, or a material having a thermal expansion coefficient slightly larger than that of each of the substrates 2 and 4, and may be made of Al, Fe, Ni, Co. Of these, it is desirable to be formed of a metal material containing at least one element. In the present embodiment, the metal wire 8b is formed by flattening a metal wire made of a 50% Ni—Fe alloy. In the present embodiment, the length of the metal wire 8 b is set to a length that exceeds the length of the long side of the vacuum envelope 10.

  Then, the glass paste is cured with the inner surfaces 31a and 32a of the two molds 31 and 32 being in contact with each other, and the molds 31 and 32 are released as shown in FIG. Thus, an assembly 35 is obtained in which a plurality of columnar spacers 8a as shown in FIG. Further, the assembly 35 is fired to manufacture the connecting spacer 8 as schematically shown in FIG.

  As described above, since the connecting spacer 8 of the present embodiment connects the plurality of columnar spacers 8a using the flat strip-shaped metal wires 8b, the rigidity against torsion is improved. That is, when both ends of the connecting spacer 8 are held and positioned with respect to the substrate, the metal wire 8b can be prevented from being twisted, and the axes of all the columnar spacers 8a can be easily orthogonal to the substrate. In addition, since the plurality of columnar spacers 8a are attached to the metal wires 8b so that the width direction of the metal wires 8b penetrates substantially the center of all the columnar spacers 8a in a posture along the axial direction of each columnar spacer 8a. The rigidity with respect to the bending along the width direction of the wire 8b is high. In particular, the movement of each columnar spacer 8a in the axial direction is restricted, and variations in the contact height with respect to the substrates 2 and 4 can be substantially eliminated. That is, by using the connecting spacer 8 of the present embodiment, the plurality of columnar spacers 8a can be positioned and arranged with respect to the substrate simultaneously and accurately, the productivity can be improved, and the yield can be increased.

Next, the manufacturing method of SED1 which has the connection spacer 8 mentioned above is demonstrated.
First, the front substrate 2 provided with the phosphor screen 12 and the metal back 14 is prepared in advance, and the rear substrate 4 provided with the electron-emitting devices 16 and the wirings 18 and with the side walls 6 bonded thereto is prepared. In addition, a plurality of sets of connecting spacers 8 having the above-described structure are prepared.

  Next, as schematically shown in FIG. 8, a plurality of sets of connecting spacers 8 are positioned and joined on the metal back 14 of the front substrate 2. The connecting spacers 8 extend in the long side direction of the front substrate 2 and are spaced apart from each other in the short side direction and provided in parallel. At this time, both ends of each connecting spacer 8 are gripped and extended in the long side direction of the front substrate 2 and positioned, and one end of the plurality of columnar spacers 8 a of the connecting spacer 8 is joined to the light shielding layer 11 of the front substrate 2. . In joining, frit glass is applied in advance to one end of each columnar spacer 8a of the connecting spacer 8, or frit glass is applied in advance to a corresponding position on the front substrate 2, and the front substrate 2 and the connecting spacer 8 are joined. To do.

  In this embodiment, since the metal wire 8b is longer than the long side of the front substrate 2, the end of the metal wire 8b is held at a position away from the front substrate 2. In other words, after the connecting spacer 8 is joined to the front substrate 2 so that the metal wire 8b fits at least inside the side wall 6 when the vacuum envelope 10 is manufactured, both ends of the metal wire 8b are cut to an appropriate length. There is a need to.

  Then, the front substrate 2 and the rear substrate 4 to which a plurality of sets of connection spacers 8 are bonded in this way are arranged in a vacuum chamber (not shown), the inside of the vacuum chamber is evacuated, and then the back surface via the side wall 6 and the connection spacer 8. The peripheral portions are sealed with the substrate 4 facing the front substrate 2. Alternatively, the peripheral portions of the front substrate 2 and the rear substrate 4 are sealed in an inert gas atmosphere, and then the inside is evacuated to manufacture the vacuum envelope 10.

  In any case, the back substrate 4 is opposed to the front substrate 2 on which the plurality of coupling spacers 8 are fixed so that the plurality of electron-emitting devices 16 are opposed to the phosphor screen 12, and the plurality of columnar spacers 8. The back substrate 4 is brought into contact with the end, and the peripheral portions of the front substrate 2 and the back substrate 4 are sealed. Thereby, SED1 provided with the connection spacer 8 which has the some columnar spacer 8a is manufactured.

  By the way, in the above-described substrate sealing step, it is necessary to heat and bake the front substrate 2 and the back substrate 4 at a high temperature for degassing the substrate, or when activating the getter, which is not described. 2 and the back substrate 4 need to be heated to a high temperature. Thus, when the front substrate 2 and the back substrate 4 are heated to a high temperature, the metal wires 8a of the connecting spacers 8 joined to the front substrate 2 are also heated and thermally expanded.

  In the present embodiment, the thermal expansion coefficient of the metal wire 8a is substantially the same as or slightly larger than the thermal expansion coefficients of the front substrate 2 and the rear substrate 4, and therefore, for example, the connecting spacer 8 is joined to the front substrate 2. Even if the connecting spacer 8 is heated in this state and the metal wire 8b is thermally expanded, the front substrate 2 also expands at substantially the same ratio, or the metal wire 8b expands slightly larger, so at least the adjacent columnar spacer 8a. There is no possibility of being attracted to each other and collapsing, and the yield can be improved.

  As described above, according to the present embodiment, since the connecting spacer 8 in which a plurality of columnar spacers 8a are arranged in a line and connected by the metal wire 8b is used, the spacers are compared with the case where the columnar spacers 8a are attached one by one. The mounting operation can be simplified, the productivity can be improved, and the manufacturing cost of the SED 1 can be reduced. In addition, since the plurality of columnar spacers 8a are connected using the strip-shaped flat metal wires 8b, the connecting spacers 8 can be prevented from being twisted and the columnar spacers 8a can be prevented from being displaced in the height direction. The contact height can be made uniform, stress can be prevented from being concentrated on the specific columnar spacer 8a, and the yield can be increased.

  In the above-described embodiment, the connection spacer 8 in which a plurality of columnar spacers 8a are connected by a flat strip-shaped metal wire 8b is used. However, the present invention is not limited to this, and a connection spacer 40 as shown in FIGS. 9 and 10 is used. It may be used.

  The connecting spacer 40 has a structure in which a plurality of columnar spacers 42 are connected by two metal wires 44 and 45 covered with an insulating material such as glass or ceramic. On the side surface of each columnar spacer 42, two annular grooves 46, 47 are formed which are provided over the entire circumference at two positions spaced apart in the axial direction. Then, the metal wire 44 is wound around one groove 46 of each columnar spacer 8a, and the metal wire 45 is wound around the other groove 47, and the plurality of columnar spacers 42 are connected in parallel with each other at a predetermined distance. Has been. The connecting spacer 40 is formed with a thin film having a surface resistance of 1 × 10E7Ω / □ to 1 × 10E12Ω / □ and a film thickness of 10 nm to 1 μm on the outermost layer by a method such as sputtering, vapor deposition, or immersion. Yes. This connecting spacer 40 is also attached to the front substrate 2 as schematically shown in FIG.

  The metal wires 44 and 45 of the connecting spacer 40 are also formed of the same material as that of the front substrate 2 and the rear substrate 4, that is, the same material as the metal wire 8 b of the connecting spacer 8 described above. The metal wires 44 and 45 can also be formed into a flat band shape, but it is not necessary. By connecting the columnar spacers 42 at two positions spaced in the axial direction of the columnar spacers 42, the above-described band-shaped metal is provided. An effect similar to that of the wire 8b can be obtained. That is, the connecting spacer 40 has high rigidity against torsion, and can have high rigidity against bending along the axial direction of the columnar spacer 42.

  When this connection spacer 40 is used, the same effects as those of the connection spacer 8 described above can be obtained, and the metal wires 44 and 45 can be prevented from being undesirably charged during the operation of the SED 1. The trajectory of the electron beam emitted from the laser beam is not affected. Further, the discharge current can be suppressed within a specified value without increasing the discharge current due to the discharge.

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. Various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the above-described embodiments. For example, you may delete some components from all the components shown by embodiment mentioned above. Furthermore, you may combine the component covering different embodiment suitably.

  For example, in the above-described embodiment, the case where the connection spacer 8 is extended along the long side of the vacuum envelope 10 has been described. However, the connection is not limited to this, and the connection is performed along the short side of the vacuum envelope 10. The spacer 8 may be extended. Further, in the above-described embodiment, after attaching the connecting spacer to the front substrate 2, the rear substrates are made to face each other and the peripheral portions are sealed to each other. However, after attaching the connecting spacer to the rear substrate 4, the front substrate is attached to the front substrate. You may seal it facing. Furthermore, in the above-described embodiment, the case where the spacer has a cylindrical shape has been described. However, the shape is not limited to this, and any shape may be used as long as it supports the front substrate 2 and the back substrate 4.

1 is an external perspective view showing a vacuum envelope of an SED according to an embodiment of the present invention. FIG. 2 is a cross-sectional perspective view of the vacuum envelope of FIG. 1 cut along line II-II. The partial expanded sectional view which expands and shows the cross section of FIG. 2 partially. The figure for demonstrating the method to manufacture the connection spacer integrated in SED of FIG. The top view which shows the inner surface of the type | mold of FIG. The figure for demonstrating the method to manufacture a connection spacer. FIG. 3 is an external view partially showing the assembly after releasing the mold. The schematic diagram which shows the state which attached the connection spacer to the front substrate. The external view which shows the modification of a connection spacer. The top view which looked at the connection spacer of FIG. 9 from the axial direction of the columnar spacer. The schematic diagram which shows the state which attached the connection spacer of FIG. 9 to the front substrate.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... SED, 2 ... Front substrate, 4 ... Back substrate, 6 ... Side wall, 8, 40 ... Connection spacer, 8a, 42 ... Columnar spacer, 8b, 44, 45 ... Metal wire, 10 ... Vacuum envelope, 12 ... Phosphor screen, 14 ... metal back, 16 ... electron-emitting device, 18 ... wiring, 46, 47 ... groove.

Claims (10)

A first substrate having a phosphor layer;
A second substrate having excitation means for exciting the phosphor layer;
A spacer structure disposed in contact between the first and second substrates,
The spacer structure is
A plurality of columnar spacers whose both ends are in contact with the first and second substrates, respectively;
A connecting member in which the plurality of columnar spacers are connected in parallel in a row;
A display device comprising:   The connection member is formed of a material having a thermal expansion coefficient substantially the same as that of the first and second substrates, or a material having a thermal expansion coefficient slightly larger than that of the first and second substrates. The display device according to 1.   The display device according to claim 1, wherein the connecting member is formed of a metal wire containing at least one element of Al, Fe, Ni, and Co.   The display device according to claim 3, wherein the metal wire is covered with an insulating material.   5. The display device according to claim 4, wherein the metal wire has a thin film having a surface resistance of 1 × 10E7Ω / □ to 1 × 10E12Ω / □ and a film thickness of 10 nm to 1 μm as an outermost layer.   The said connecting member has two said metal wires which respectively connect two positions spaced apart in the longitudinal direction of each of the plurality of columnar spacers arranged in a row to which the connecting member is connected. Display device.   The display device according to claim 3, wherein the metal wire is formed in a flat belt shape. Providing a first substrate having a phosphor layer and a second substrate having an excitation means for exciting the phosphor layer;
Preparing a spacer structure having a plurality of columnar spacers and a connecting member in which the plurality of columnar spacers are aligned and connected in parallel with each other;
Holding both ends of the connecting member, positioning the spacer structure on the first substrate, and fixing one end of each of the plurality of columnar spacers to the first substrate;
The second substrate is made to face the first substrate having the spacer structure so that the excitation means faces the phosphor layer, and the second substrate is brought into contact with the other ends of the plurality of columnar spacers. Sealing the peripheral portions of both substrates;
A method for manufacturing a display device, comprising:   9. The display device according to claim 8, wherein in the step of preparing the spacer structure, the spacer structure is manufactured by forming the plurality of columnar spacers with glass paste or ceramic paste along the connecting member. Manufacturing method.   9. The method for manufacturing a display device according to claim 8, wherein, in the step of preparing the spacer structure, the spacer structure is manufactured by winding the plurality of columnar spacers with the connecting member.

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