JP2008251365A - Image display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To supply a positive electrode voltage at a high voltage to an anode substrate with high reliability, in an FED (field emission display device). <P>SOLUTION: A high-voltage introduction terminal 60 is sealed to an exhaust substrate 6 mounted on a cathode substrate 1 side. A contact spring 50 is spot-welded to the high-voltage introduction terminal 60. The contact spring 50 supplies a high voltage to the anode substrate 2 by contacting an anode terminal 24 formed on the anode substrate 2. The anode terminal 24 is formed with a film formed by sintering conductive paste prepared by dispersing silver particles and silver flakes in frit glass containing vanadium oxide as a main constituent. The frit glass never adversely affects the environment because it does not contain lead. Since the silver flakes are used together with the silver particles, reliability of conduction of the anode terminal 24 is high. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method for supplying an anode voltage in a flat display device in which the inside is evacuated, electron emission sources are arranged in a matrix on a rear substrate, and phosphors corresponding to the front substrate are arranged.

  Conventionally, a color cathode ray tube has been widely used as a display device excellent in high luminance and high definition. However, the demand for flat image display devices is increasing from the viewpoint of space saving and light weight. Liquid crystal display devices, plasma display devices, and the like are not so heavy even if they have a large screen of 30 inches or more, and therefore, the demand is expanding not only in small display devices but also in the field of large display devices such as TVs.

  On the other hand, development of so-called field emission display device (FED) in which the inside between two glass substrates is evacuated, electron emission sources are arranged in a matrix on one substrate, and phosphors are arranged on the opposite substrate. Is progressing. The FED forms an image when electrons from an electron emission source impinge on a phosphor and emits light. In the future, brightness, contrast, moving image characteristics, etc. can provide excellent performance equivalent to a cathode ray tube. It is expected as a TV display.

  However, in the FED, it is necessary to accelerate electrons to make the phosphor shine by applying a high voltage of about 10 KV to the anode. Supplying a high voltage of 10 KV to one substrate with sufficient reliability is a difficult problem, and various devices and inventions are disclosed. There are [Patent Literature 1], [Patent Literature 2], [Patent Literature 3], [Patent Literature 4], [Patent Literature 5] and the like as disclosures of such a high voltage supply method. These patent documents disclose the use of a coil spring, a leaf spring, etc. as a method for sealing the high voltage introduction terminal and a method for contacting the high voltage introduction terminal and the anode, but they have not yet been put into practical use.

JP 10-31433 A Japanese Patent Laid-Open No. 10-326581 JP 2000-31636 A JP 2003-115271 A Japanese Patent Laid-Open No. 5-114372

  In the above prior art, a high voltage introduction pin is installed on the opposite substrate of the anode substrate to which a high voltage is applied, that is, the cathode substrate side, and a high voltage is applied to the anode substrate through a coil spring or a leaf spring attached to the high voltage introduction pin. Supply. The coil spring has a problem in the reliability of the connection between the high voltage introduction pin or the contact between the coil spring and the anode. In addition, when a high voltage is supplied from the outside to the inside of the display device using a pin that penetrates the cathode substrate or the like, there may be a problem of vacuum tightness at a portion where the pin penetrates.

  On the other hand, when a leaf spring is used, contact between the tip of the leaf spring and the voltage supply terminal (anode terminal) of the anode substrate becomes a problem. That is, since the leaf spring is in mechanical contact with the anode terminal with a certain pressure, if the anode terminal is a soft material, the anode terminal is scraped off and becomes a foreign substance in the tube. This foreign matter in the tube causes a spark between the anode substrate and the cathode substrate.

  In order to take measures against the problem of the anode terminal being scraped off, the anode terminal can be made by applying a silver paste in which silver particles are dispersed in a lead-containing frit glass and sintering it. However, lead-containing frit glass causes environmental problems. Even when such a silver paste is used, there is a problem that a part of the anode terminal is peeled off depending on the shape of the anode terminal.

  An object of the present invention is to overcome the above-described problems and supply a high voltage to the anode substrate with high reliability.

  The present invention has been made to solve the above-described conventional problems, and main means are as follows.

(1) a cathode substrate having an electron emission source formed in a matrix, and an anode substrate facing the cathode substrate and having a phosphor formed at a location corresponding to the electron emission source and to which an anode voltage is applied A display device in which a vacuum is maintained, wherein a glass substrate is attached to the cathode substrate via a sealing portion, and a high voltage introduction terminal for supplying the anode voltage is sealed on the glass substrate. A connecting member for connecting to the anode substrate is connected to the high voltage introduction terminal, the connecting member is connected to an anode terminal formed on the anode substrate, and the anode terminal is made of vanadium oxide. A display device comprising a film in which silver particles and silver flakes are dispersed in frit glass as a main component.
(2) The display device according to (1), wherein a ratio of silver at the anode terminal is 60% by weight to 95% by weight.
(3) When the sum total of the said silver particle and the said silver flake is set to 100, the said silver flake is 50 or more, The display apparatus as described in (1) characterized by the above-mentioned.
(4) The display device according to (1), wherein the silver flakes are 70 ± 10 when the total of the silver particles and the silver flakes is 100.
(5) The display device according to (1), wherein a metal back is formed on the anode substrate so as to cover the phosphor, and the anode terminal is formed on the metal back.
(6) The display device according to claim 1, wherein the anode substrate and the cathode substrate are sealed with frit glass mainly composed of vanadium oxide through a frame.
(7) The display device according to (1), wherein the high voltage introduction terminal is sealed to a glass substrate by frit glass mainly composed of vanadium oxide.
(8) The display device according to (1), wherein the cross section of the anode terminal is such that the film thickness of the thickest portion of the end is 1.5 times or less of the average film thickness of the anode terminal.
(9) The display device according to (1), wherein the anode terminal has a rectangular shape with a corner portion having R, and the R is 1 mm or more.

(10) a cathode substrate having an electron emission source formed in a matrix, and an anode substrate facing the cathode substrate and having a phosphor formed at a location corresponding to the electron emission source and to which an anode voltage is applied A display device in which a vacuum is maintained, wherein a glass substrate is attached to the cathode substrate via a sealing portion, and a high voltage introduction terminal for supplying the anode voltage is sealed on the glass substrate. A connecting member for connecting to the anode substrate is connected to the high voltage introduction terminal, the connecting member is connected to an anode terminal formed on the anode substrate, and the anode terminal contains lead. A display device characterized by being a film in which silver particles and silver flakes are dispersed in a non-frit glass.
(11) The display device according to (10), wherein a ratio of silver at the anode terminal is 60% by weight to 95% by weight.
(12) The display device according to (10), wherein the silver flakes are 50 or more when the total of the silver particles and the silver flakes is 100.
(13) The display device according to (10), wherein the anode substrate and the cathode substrate are sealed with frit glass containing no lead through a frame.

(14) a cathode substrate in which an electron emission source is formed in a matrix; an anode substrate facing the cathode substrate and having a phosphor formed at a location corresponding to the electron emission source and to which an anode voltage is applied; A display device in which a vacuum is maintained, wherein a glass substrate is attached to the cathode substrate via a sealing portion, and a high voltage introduction terminal for supplying the anode voltage is sealed on the glass substrate. A connecting member for connecting to the anode substrate is connected to the high voltage introduction terminal, the connecting member is connected to a plate-like metal anode terminal installed on the anode substrate, and the metal anode A display device, wherein the terminal is bonded to the anode substrate by conductive frit glass.
(15) The display device according to (14), wherein the metal anode terminal is formed of a disk-shaped Fe—Ni alloy.
(16) The display device according to (14), wherein the metal anode terminal is made of an alloy of Fe 52 wt% -Ni 48 wt%.
(17) The display device according to (14), wherein the conductive frit glass is bonded to a frit glass mainly composed of vanadium oxide by a film in which silver particles and silver flakes are dispersed.
(18) The display device according to (14), wherein the metal anode terminal is formed on a metal back made of an Al film formed on the anode substrate.
(19) The display device according to (14), wherein the connection member is a metal contact spring.
(20) The display device according to (14), wherein the conductive frit glass is bonded to a frit glass containing no lead as a component by a film in which silver particles and silver flakes are dispersed.

  In the present invention, a sintered film of silver paste in which silver particles and silver flakes are dispersed in a frit glass mainly composed of vanadium oxide is used for the anode terminal formed on the anode substrate, so that environmental pollution due to lead does not occur. . In addition, since silver particles and silver flakes are used, the metal back and conduction can be reliably provided. Furthermore, by making the film thickness and shape of the anode terminal special, partial peeling of the node terminal can be prevented.

  In another embodiment of the present invention, a thin metal plate having a thermal expansion coefficient close to that of glass is used as the anode terminal. A high voltage is supplied from a high voltage introduction terminal formed on the cathode substrate side via a contact spring or the like as a connecting member. When the anode terminal is formed of conductive frit glass or the like, the contact portion of the contact spring may be adhered to the frit glass. The contact spring is formed of a spring material such as Inconel, and has a thermal expansion coefficient different from that of glass, so that the glass cracks when bonded to the glass. In another embodiment of the present invention, since a thin sheet of Fe—Ni alloy combined with glass and a thermal expansion coefficient is used as the anode terminal, the contact spring is not bonded to the glass. Therefore, a high voltage can be supplied to the anode substrate with high reliability.

  The best mode of the present invention will be described below in detail with reference to the drawings of the embodiments.

  FIG. 1 is a plan view showing a first embodiment of the present invention. 2 is a side view of FIG. 1, FIG. 3 is a sectional view taken along line AA in FIG. 1, and FIG. 4 is a sectional view taken along line BB in FIG. In FIG. 1, an anode substrate 2 is installed on a cathode substrate 1 via a sealing portion 3. On the cathode substrate, scanning lines extend in the horizontal direction and data signals extend in the vertical direction. A signal is supplied to the scanning line and the data signal line from the outside via the terminal 5. An electron emission source is disposed near the intersection of the scanning line and the signal line. Therefore, a large number of electron emission sources are arranged in a matrix. Various electron emission sources such as the so-called MIM method, SED method, and Spindt method have been developed. Any electron emission source can be applied to the present invention.

  The inside of the sealing part 3 surrounding the cathode substrate 1 and the anode substrate 2 and the periphery is kept in a vacuum. Therefore, the anode substrate 2 and the cathode substrate 1 are bent by the atmospheric pressure, and the interval between the cathode substrate 1 and the anode substrate 2 cannot be secured. Alternatively, the cathode substrate 1 or the anode substrate 2 is destroyed. In order to avoid this, a spacer 4 is provided between the cathode substrate 1 and the anode substrate 2. The spacer 4 is made of ceramic or glass and is generally installed on the scanning line so as not to hinder image formation.

  On the anode substrate, red, green, and blue phosphors that emit light by the impact of an electron beam are formed corresponding to the electron emission source. A black matrix (BM) is formed around the phosphor to improve image contrast. A metal backing made of Al is formed covering the black matrix. A high voltage is applied to the metal back, and the electron beam emitted from the cathode is accelerated and projected onto the phosphor 21.

  In order to generate light from the phosphor by the electron beam, the electron beam must have a certain amount of energy, so that a high voltage of 8 KV to 10 KV is applied to the metal back of the anode substrate 2. In this embodiment, an external high voltage introduction terminal 60 is provided on the cathode substrate side, and a high voltage is supplied to the anode substrate 2 via a contact spring. In FIG. 1, an anode terminal where the contact spring contacts the anode substrate 2 is formed at a corner portion of the display device. Since the inside of the display device must be kept in a vacuum, exhaust holes 81 for exhaust are formed at the corners of the display device in FIG.

  FIG. 2 is a side view of FIG. 1 viewed from the D direction. In FIG. 2, the cathode substrate 1 and the anode substrate 2 face each other with a predetermined distance through the sealing portion 3. The cathode substrate 1 is formed larger as the terminals 5 and the like are installed. Under the cathode substrate 1, an exhaust substrate 6 for attaching the exhaust pipe 8 and the high voltage introduction terminal 60 is attached. The exhaust substrate 6 is attached to the cathode substrate 1 via an exhaust substrate sealing portion 7. In FIG. 2, an exhaust pipe 8 for evacuating the inside of the display device is drawn on the exhaust substrate 6 in a state where the chip is turned off. A high voltage introduction terminal 60 is attached near the exhaust pipe 8.

3 is a cross-sectional view taken along the line AA in FIG. In FIG. 3, the data signal line 12 extends in a direction perpendicular to the paper surface. In this embodiment, an electron emission source 13 is formed on the data signal line 12. The scanning line 11 is formed in a direction perpendicular to the data signal line 12 through the insulating film 14. In FIG. 3, the scanning line 11 extends outside the sealing portion 3. A spacer 4 for maintaining the distance between the cathode substrate 1 and the anode substrate 2 is provided on the scanning line 11. The spacer 4 is fixed to the scanning line on the cathode substrate side by the fixing material 41 and to the metal back 23 on the anode substrate side. The spacer 4 has a conductivity of about 10 ⁸ to 10 ⁹ Ω, and the spacer 4 is prevented from being charged by passing a slight current between the cathode and the anode.

  On the anode substrate side, phosphors 21 such as red, green, and blue are arranged at locations corresponding to the electron emission sources 13, and the phosphors 21 emit light by being projected by an electron beam, thereby forming an image. Is done. The space between the phosphors 21 is filled with BM 22 and contributes to the improvement of the contrast of the image. For example, the BM 22 has a two-layer structure of chromium and chromium oxide. A metal back 23 made of Al is formed so as to cover the phosphor 21 and the BM 22. A high voltage of about 8 KV to 10 KV is applied to the metal back 23 to accelerate the electron beam. The accelerated electron beam penetrates the metal back 23 and strikes the phosphor 21 to cause the phosphor 21 to emit light. Although a high voltage is applied to the metal back 23, it is an important subject of the present invention to supply this high voltage with reliability.

  In order to keep the inside of the display device in a vacuum, the cathode substrate 1 and the anode substrate 2 are sealed by the frame member 31 and the sealing material 32. The thickness of the cathode substrate 1 and the thickness of the anode substrate 2 are about 3 mm. The distance between the cathode substrate 1 and the anode substrate 2 is about 2.8 mm, and the inside of the display device has a high electric field.

  FIG. 4 is a cross-sectional view taken along the line BB of FIG. 1 and shows a main part of the first embodiment. In FIG. 4, a through hole 10 is formed in the cathode substrate 1, and the display device is exhausted or a high voltage is supplied through the through hole 10. An exhaust substrate 6 is installed through the exhaust substrate sealing portion 7 so as to cover the through hole 10 of the cathode substrate 1, and the inside of the display device is kept in vacuum. The exhaust board sealing portion 7 is a general term for the exhaust board frame 71 and the sealing material 32. The exhaust substrate sealing portion 7 has the same basic configuration as the cathode substrate 1 and the anode substrate 2 sealing portion 3. That is, the exhaust substrate frame 71 is sealed to the cathode substrate 1 and the anode substrate 2 via the sealing material 32. In this embodiment, the frame 31 for sealing the anode substrate 2 and the cathode substrate 1 and the frame for sealing the cathode substrate 1 and the exhaust substrate 6 have the same thickness, but the thickness of the frame is as required. Can be set freely.

  The high voltage introduction terminal 60 is sealed to the exhaust board 6 to keep airtight with the outside. An Fe—Ni alloy is used for the high voltage introduction terminal 60. The component ratio of the Fe—Ni alloy is selected so as to match the thermal expansion coefficient with the sealing material 32. Fe 52% and Ni 48% are preferable. A contact spring 50 is spot welded to the flat portion 61 of the high voltage introduction terminal 60. FIG. 5 is a perspective view showing a state in which the contact spring 50 is spot welded to the high voltage introduction terminal 60. In FIG. 5, the upper surface of the flange portion 62 of the high voltage introduction terminal 60 is sealed to the exhaust substrate 6 via frit glass. The high voltage introduction terminal 60 is formed with a protrusion 63 for connecting to an external socket.

  The contact spring 50 is made of Inconel, which can be easily spot welded with the Fe—Ni alloy. The contact spring 50 is formed of a base portion 51, an arm portion 52, and a contact portion 53 that are connected to the high voltage introduction terminal 60. The contact portion 53 of the contact spring 50 comes into contact with the metal back 23 formed on the anode substrate 2 by an appropriate force due to bending stress caused by the bending of the arm portion 52 of the contact spring 50. The contact pressure of the contact spring 50 in the present embodiment is about 10 g, but may be larger than 10 g due to component variations. The contact portion 53 of the contact spring 50 has an appropriate curved surface such as a spherical surface, and is formed so as to be in stable contact with the anode terminal 24. Inconel is used for the material of the contact spring 50 in consideration of heat resistance and the thickness is 0.1 mm.

  As shown in FIG. 4, one of the advantages of attaching the high voltage introduction terminal 60 to the exhaust board 6 is that the high voltage introduction terminal 60 is sealed on the relatively small exhaust board 6. The process of sealing can be streamlined. That is, since the exhaust substrate 6 is much smaller than the cathode substrate or the like, a large number of high voltage introduction terminals 60 can be sealed at a time. Further, when sealing to a cathode substrate or the like, there is a problem that an expensive large-sized substrate must be discarded when a sealing failure of the high voltage introduction terminal 60 occurs. On the other hand, if the high voltage introduction terminal 60 is sealed on the exhaust board 6, even if the sealing failure of the high voltage introduction terminal 60 occurs, only the small exhaust board 6 becomes defective, so that the damage is kept small. I can do it.

  An anode terminal 24 for contacting the contact spring 50 is formed on the anode substrate 2. Since a large current flows through the anode terminal 24, reliability is important. Further, since the anode terminal 24 is pressed by the contact spring 50, it must be mechanically strong. Furthermore, since a large current flows between the contact spring 50 and the anode terminal 24, it is necessary to have a configuration with a small electrical resistance so as not to generate a large amount of heat in this portion. Further, even when heat is generated, the structure needs to withstand this heat.

  FIG. 6 is a schematic plan view of the anode substrate 2 in the vicinity where the anode terminal 24 is formed. In FIG. 6, the sealing part 3 is formed in the peripheral part of the anode substrate. In the display area 100, phosphors 21 corresponding to a large number of pixels for forming an image are formed. A black matrix 22 and a metal back 23 are formed in an area larger than the display region 100. Since the black matrix 22 and the metal back 23 are formed in the same area, only the metal back 23 is shown in FIG. The black matrix 22 and the metal back 23 extend to the vicinity of the sealing portion 3 at the corner portion. An anode terminal 24 is formed on the extended metal back 23 at the corner.

  In this embodiment, the structure near the anode terminal 24 is as follows. That is, a conductive film as the anode terminal 24 is formed on the metal back 23 with a thickness of 5 μm to 30 μm. The shape of the anode terminal 24 in FIG. 6 is circular, and the diameter is 20 mm or less, preferably 10 mm or less. In this embodiment, the conductive film is formed by applying a silver paste by printing and then baking. There is no need to provide a special process for firing the conductive film. For example, it may be performed simultaneously with the firing process for fixing the spacer 4.

The silver paste used in this example is not an ordinary silver paste, but is a frit glass in which silver particles and silver flakes are dispersed. Conventionally, lead-based frit glass has been used as the frit glass. However, in order to consider environmental problems, non-lead-based frit glass is used in the present invention. In this embodiment, vanadium frit glass is used. Vanadium-based frit glass (hereinafter referred to as V frit) is roughly classified into an insulating type and a conductive type. The components of the insulating V frit are, for example, V ₂ O ₅ : 50%, P ₂ O ₅ : 10%, BaO: 20%, WO ₃ : 15%, TeO ₂ : 15% + balance. On the other hand, the components of the conductive V frit are, for example, V ₂ O ₅ : 50% to 60%, P ₂ O ₅ : 25%, BaO: 5%, and Sb2O3: balance. The above component is a component after V frit sintering, and is a component ratio when silver particles or silver flakes are removed. In both cases of the insulating V frit and the conductive V frit, vanadium oxide is the main component. At the time of application, the V frit in which silver particles or silver flakes are dispersed is pasty, and the above components are dispersed in a vehicle. The vehicle scatters and disappears during baking after application.

The conventional silver paste has only silver particles dispersed therein, but the silver paste of this example is one in which silver particles or silver flakes are dispersed in a V frit. According to the inventor's experiment, the resistance cannot be sufficiently reduced with a silver paste using only silver particles as in the prior art. In particular, when a V frit is used as the frit glass as in this embodiment, the resistance value becomes a problem. That is, the V frit is mainly composed of an oxide such as V ₂ O ₅ . When such an oxide is formed on the metal back 23 made of Al, Al is oxidized, and alumina Al ₂ O ₃ is formed between the anode terminal 24 and the metal back, and sufficient conduction may not be obtained. .

In this embodiment, the problem that the resistance value becomes large is solved by dispersing silver flakes together with silver particles. That is, be formed between alumina Al ₂ O ₃ is the anode terminal 24, it is possible to obtain conductivity destroying the alumina Al ₂ O ₃ to the edge portion of the silver flake is formed thinly. FIG. 7 shows silver particles in a silver paste conventionally used. Silver particles have a diameter of 1 μm to several μm. Although FIG. 7A is spherical, in practice, the surface is not a smooth sphere, and the surface as shown in FIG. 7B is often a rough sphere.

FIG. 8 shows an example of flaky silver particles. Silver flakes can take a variety of shapes. FIG. 8A shows an example of a disk-like flake. FIG. 8B is an example of plate-like flakes. The shape of the silver flakes may be any shape. If it is flake-shaped, the alumina film Al ₂ O ₃ formed thinly between the metal back and the anode terminal 24 can be destroyed to avoid poor conduction. The ratio of silver flakes to silver particles is preferably 50% or more of silver flakes. In addition, if the ratio of silver flakes is 70% ± 10%, the effect can be maximized. In this case,% is% by weight. In this embodiment, the silver ratio at the anode terminal 24, that is, the total ratio of silver particles and silver flakes is 60% by weight to 95% by weight.

  On the other hand, the planar shape and the cross-sectional shape of the anode terminal 24 are also important for the withstand voltage characteristics of the FED. FIG. 9 shows an example of the outer shape of the anode terminal 24 and its cross-sectional shape. Since the anode terminal 24 is formed by a printing method, the anode terminal 24 is formed in a shape such as a rectangle or a parallelogram as shown in FIGS. 9A and 9B for ease of pattern formation. However, in the case of such a shape, the coating film is easily peeled off at the corner portion cor shown in FIGS. 9A and 9B. Further, as shown in FIG. 9C, the cross-sectional shape has a problem that the film is easily peeled off because the film thickness te at the end is larger than the film thickness tc at the center. Further, when the film thickness is increased, the difference between the film thickness tc at the central portion and the film thickness te at the end portion is further increased, and the film is easily peeled off. In the conventional example, the difference between the film thickness tc at the center and the film thickness te at the end is often twice or more.

  In this embodiment, in order to prevent the anode terminal 24 from being peeled off, the outer shape of the anode terminal 24 is a circle having a diameter DC as shown in FIG. Of course, not only a circle but also an ellipse may be used. If there are no sharp edges, the risk of delamination is reduced. As shown in FIG. 10B, the cross-sectional shape of the anode terminal 24 is ideally such that the film thickness te at the end is smaller than the central film thickness tc. When it is difficult to form such a cross-sectional shape, as shown in FIG. 10C, the film thickness te at the end is preferably set within a range of about 1.5 times the central film thickness tc. . Or when the average film thickness of the anode terminal 24 is set to tm, it is good to make the film thickness of an edge part into 1.5 times or less of the average film thickness tm.

  It is difficult to increase the film thickness of the anode terminal 24 in order to realize the cross-sectional shapes as shown in FIGS. 10 (b) and 10 (c). On the other hand, if it is made extremely thin, problems arise in the mechanical strength against the contact spring and the heat resistance when heat is generated at the terminal. In this embodiment, the thickness of the anode terminal 24 is in the range of 5 μm to 30 μm, preferably 5 μm to 25 μm, thereby avoiding problems such as mechanical strength and heat generation of the anode terminal 24, and having a shape that prevents peeling. I can do it.

  FIG. 11 shows an example in which the outer shape of the anode terminal 24 is a square or a rectangle with rounded corners. The side lengths DX and DY in FIG. 11 are 10 mm. The effect can be improved even if the corner R is not large. For example, if the corner R is 1 mm or more, a sufficient effect can be obtained. As in the case of FIG. 10, the cross-sectional shape is best in FIG. 10 (b), but when it is difficult to manufacture, the film thickness at the end is 1 with respect to the film thickness at the center as shown in FIG. 11 (c). .5 times or less is preferable. Alternatively, when the average film thickness of the anode terminal 24 is tm, the film thickness te at the end is preferably 1.5 times or less of tm.

As described above, the V frit has insulation and conductivity. In this embodiment, any insulating or conductive V frit can be used. This is because the conduction between the contact spring and the metal back is carried by silver particles or silver flakes dispersed in the V frit. If conductive V frit is used, silver particles or silver flakes may not be dispersed, but in reality, a thin film of alumina Al ₂ O ₃ is formed on the surface of the metal back due to the influence of the V frit. Therefore, the conduction resistance varies. Therefore, it is necessary to disperse silver particles or silver flakes even when a conductive V frit is used.

  As described above, according to the present embodiment, since the anode terminal 24 is formed by the silver paste using frit glass that does not use lead, the environment can be prevented from being contaminated by lead and a stable high voltage can be supplied. Can be done. Furthermore, by preventing the anode terminal 24 from peeling off, it is possible to prevent the breakdown voltage of the FED from deteriorating.

  The second embodiment is an example in which the present invention is applied when the configuration of a high voltage supply method is different. FIG. 12 shows an example in which the contact spring comes into contact from directly below the anode terminal 24. FIG. 13 is a perspective view showing the shape of the contact spring used in FIG. In FIG. 12, the exhaust pipe formed on the exhaust board 6 is formed inside the high voltage introduction terminal. This is because the anode terminal 24 is disposed in the corner portion in order to sufficiently take up the display area 100. In the case of the configuration using such a contact spring, the same shape of the anode terminal 24 as described in the first embodiment can be applied.

  FIG. 14 shows another example in which the contact spring contacts from below the anode terminal 24. FIG. 15 is a perspective view showing the shape of the contact spring used in FIG. In FIG. 14, the exhaust pipe 8 formed on the exhaust substrate 6 is formed inside the high voltage introduction terminal 60. This is because the anode terminal 24 is disposed in the corner portion in order to sufficiently take up the display area 100. The configuration of the anode terminal 24 similar to that described in the first embodiment can be applied to the configuration using the contact spring as shown in FIG.

  The third embodiment is an example in which the present invention is applied when the configuration of the high voltage supply method is further different. The third embodiment is an example in which the exhaust pipe is not installed on the exhaust board 6 to which the high voltage introduction terminal is attached, but the exhaust pipe is formed by forming the exhaust board 6 at another corner. FIG. 16 is a plan view of the third embodiment. 17 is a side view of FIG. 16, FIG. 18 is a rear perspective view of the third embodiment, and FIG. 19 is a cross-sectional view taken along line BB of FIG.

  In FIG. 16, the anode terminal 24 is formed at the lower right of the display area 100, and the exhaust holes 81 for exhaust are formed at two places on the left side of the display area 100. FIG. 17 is a side view of FIG. 16 viewed from the D direction. In FIG. 17, the high voltage introduction terminal 60 is visible on the right side, and the exhaust pipe 8 for exhaust is visible on the left side. FIG. 18 is a perspective view of the display device of Example 3 as viewed from the back. In FIG. 18, the high voltage introduction terminal 60 is formed at one place and the exhaust pipe 8 is formed at two places. Thus, each structure is simplified by installing the high voltage introduction terminal 60 and the exhaust pipe 8 in different places. Exhaust speed can be increased by using two exhaust pipes.

  19 is a cross-sectional view taken along the line BB in FIG. As shown in FIG. 19, only the high voltage introduction terminal is formed on the exhaust substrate 6. The anode terminal 24 with which the contact spring 50 contacts has the same structure as in the first embodiment. Therefore, all the configurations described in the first embodiment can be applied. The contact spring used in the example described in the second embodiment is used. However, the other contact spring described in the second embodiment may be used, or the contact spring described in the first embodiment may be used. Also good.

  Examples 1 to 3 are examples in which V frit in which silver particles or silver flakes are dispersed is used as the anode terminal 24. A spring material such as a contact spring contacts the anode terminal 24 not only in the V frit but also in an anode terminal made of silver paste in which conductive particles or the like are dispersed in a lead-based frit. In this case, the contact spring or the like may adhere to the conductive frit unless the conductive frit is sufficiently sintered. If the contact spring adheres to the anode substrate with frit glass, the anode substrate may be broken at that portion.

  That is, since Inconel or the like, which is a material for the contact spring, has a different thermal expansion coefficient from glass, the anode substrate is distorted during the process of bonding the contact spring by frit glass, and the glass is cracked. The present embodiment counters such problems.

  A plan view of the display device is the same as FIG. FIG. 20 is a cross-sectional view taken along the line BB in FIG. 1 and shows a main part of this embodiment. Similar to the first embodiment, the black matrix 22 and the metal back 23 are formed on the anode substrate in an overlapping manner. On the metal back 23, a metal anode terminal 242 made of a disk-like metal is bonded via a bonding silver paste 241. Since the contact spring is in contact with the metal anode terminal 242, there is no fear that the contact spring adheres to the glass substrate by the frit glass.

  FIG. 21 is a schematic plan view of the vicinity of the anode terminal of this example. The basic configuration of FIG. 21 is the same as that of FIG. FIG. 21 differs from FIG. 6 in that an adhesive silver paste 241 is first applied on the back 23 that extends to the corner, and then a disk-shaped metal anode terminal 242 is bonded. The contact spring 50 is configured to contact the metal anode terminal 242. The shape of the metal anode terminal 242 is shown in FIG. The diameter dd of the metal anode terminal 242 is 20 mm or less, preferably 10 mm or less. The plate thickness td may be 0.5 mm or less, more preferably 0.2 mm or less. The thermal expansion coefficient of the metal anode terminal 242 is important, and a material having a thermal expansion coefficient similar to that of the anode substrate that is a glass substrate is used. In this embodiment, an alloy of Fe 52% Ni 48% is used. Needless to say, the metal is not limited to FeNi alloy, and any metal can be used as long as it has the same thermal expansion coefficient as glass, such as Kovar.

  The frit for dispersing the silver particles or the like for bonding the metal anode terminal 242 is not particularly limited, but in consideration of the environment, a frit glass containing no lead is preferable. From this point, a silver paste in which silver particles or silver flakes described in Example 1 are dispersed in a V frit is preferable. In this case, the V frit is preferably formed as thin as possible to the extent necessary for adhesion as described in the first embodiment. This is to prevent peeling of the V frit.

  In FIG. 21 etc., the metal anode terminal 242 is circular. The circular shape is most advantageous for stress due to the difference in thermal expansion coefficient between the glass and the metal anode terminal 242. However, as long as there is a restriction on the installation location of the metal anode terminal 242, it is needless to say that the shape may be any shape such as an ellipse, a square, or a rectangle that is limited to a circle.

  In Examples 1 to 4, an example in which silver particles or silver flakes are dispersed in a V frit and used as an anode terminal or an adhesive for an anode terminal portion has been described. The reason for using the V frit is to prevent environmental deterioration due to lead when a lead-containing frit is used. Frit glass is often used as an FED frame member 31 and a sealing material 32 such as a high voltage introduction terminal 60. Therefore, it goes without saying that environmental deterioration can be prevented by using V frit as the sealing material 32. In addition, when using V frit as the sealing material 32, of course, it is not necessary to disperse | distribute electrically conductive substances, such as a silver particle and silver flakes.

  The above description has been made mainly assuming that the V frit is used as the frit glass, but the present invention is not limited to the V frit but can be applied to a frit glass not using lead. That is, an appropriate resistance value is set by dispersing silver particles and silver flakes in the frit glass, the shape of the anode terminal 24 is made difficult to peel off, and it is used as an adhesive for the metal anode terminal 242. The present invention is not limited to the V frit and can be similarly applied to other frit glasses not containing lead.

  In the first to fourth embodiments, the high voltage introduction terminal 60 is installed on the exhaust board 6. This is an example of a place where the high voltage introduction terminal 60 is installed. The high voltage introduction terminal 60 may be installed directly on the cathode substrate 1 as necessary. The basic configuration of the present invention can be applied even if the high voltage introduction terminal 60 is directly installed on the cathode substrate.

It is a top view which shows Example 1 of this invention. It is a side view of FIG. It is AA sectional drawing of FIG. It is BB sectional drawing of FIG. It is a figure which shows the shape of a high voltage introduction | transduction terminal. It is a top view of the anode substrate near an anode terminal. This is an example of silver particles. It is an example of silver flakes. It is a prior art example of an anode terminal shape. It is an example of the anode terminal shape by this invention. It is another example of the anode terminal shape by this invention. 6 is a cross-sectional view of a high voltage introduction part of Example 2. FIG. FIG. 13 is a perspective view of a contact spring used in FIG. 12. 6 is another structural example of the high voltage introduction portion of the second embodiment. FIG. 15 is a perspective view of a contact spring used in FIG. 14. 10 is a plan view showing Example 3. FIG. FIG. 17 is a side view of FIG. 16. 6 is a rear perspective view of Example 3. FIG. FIG. 16B is a cross-sectional view taken along the line B-B. 6 is a cross-sectional view of a high voltage introduction portion of Example 4. FIG. 6 is a plan view of an anode substrate in the vicinity of an anode terminal of Example 4. FIG. It is an example of a metal anode terminal.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Cathode substrate, 2 ... Anode substrate, 3 ... Sealing part, 4 ... Spacer, 5 ... Terminal, 6 ... Exhaust board, 7 ... Exhaust board sealing part 8 ... exhaust pipe, 11 ... scanning line, 12 ... data signal line, 13 ... electron emission source, 14 ... insulating film, 21 ... phosphor, 22 ... black Matrix, 23 ... Metal back, 24 ... Anode terminal, 50 ... Contact spring, 51 ... Base part of contact spring, 52 ... Arm part of contact spring, 53 ... Contact spring Contact part, 60 ... high voltage introduction terminal, 65 ... flange part of high voltage introduction terminal, 81 ... exhaust hole, 100 ... display area, 241 ... silver paste for bonding, 242 ...・ Metal anode terminal.

Claims (20)

A cathode substrate having an electron emission source formed in a matrix; an anode substrate facing the cathode substrate; a phosphor formed at a location corresponding to the electron emission source; and an anode voltage applied thereto; A display device maintained in a vacuum,
A glass substrate is attached to the cathode substrate via a sealing portion, and a high voltage introduction terminal for supplying the anode voltage is sealed to the glass substrate, and the anode substrate and the high voltage introduction terminal are connected to the cathode substrate. A connecting member for conducting electrical connection is connected, and the connecting member is connected to an anode terminal formed on the anode substrate, and the anode terminal has silver particles and silver flakes dispersed in frit glass mainly composed of vanadium oxide. A display device characterized by being a film formed.   The display device according to claim 1, wherein a ratio of silver at the anode terminal is 60 wt% to 95 wt%.   The display device according to claim 1, wherein the silver flakes are 50 or more when the total of the silver particles and the silver flakes is 100.   2. The display device according to claim 1, wherein the silver flakes are 70 ± 10 when the total of the silver particles and the silver flakes is 100. 3.   The display device according to claim 1, wherein a metal back is formed on the anode substrate so as to cover the phosphor, and the anode terminal is formed on the metal back.   The display device according to claim 1, wherein the anode substrate and the cathode substrate are sealed with frit glass mainly composed of vanadium oxide through a frame.   The display device according to claim 1, wherein the high voltage introduction terminal is sealed to a glass substrate by frit glass mainly composed of vanadium oxide.   2. The display device according to claim 1, wherein the cross section of the anode terminal has a thickness of a thickest portion of an end portion of 1.5 times or less of an average thickness of the anode terminal.   The display device according to claim 1, wherein the anode terminal has a rectangular shape with a corner portion having R, and the R is 1 mm or more. A cathode substrate having an electron emission source formed in a matrix; an anode substrate facing the cathode substrate; a phosphor formed at a location corresponding to the electron emission source; and an anode voltage applied thereto; A display device maintained in a vacuum,
A glass substrate is attached to the cathode substrate via a sealing portion, and a high voltage introduction terminal for supplying the anode voltage is sealed to the glass substrate, and the anode substrate and the high voltage introduction terminal are connected to the cathode substrate. A connection member for conducting electricity is connected, the connection member is connected to an anode terminal formed on the anode substrate, and the anode terminal is a film in which silver particles and silver flakes are dispersed in a frit glass not containing lead. A display device characterized by the above.   The display device according to claim 10, wherein a ratio of silver at the anode terminal is 60 wt% to 95 wt%.   The display device according to claim 10, wherein the silver flakes are 50 or more when the total of the silver particles and the silver flakes is 100.   The display device according to claim 10, wherein the anode substrate and the cathode substrate are sealed with frit glass containing no lead via a frame. A cathode substrate having an electron emission source formed in a matrix; an anode substrate facing the cathode substrate; a phosphor formed at a location corresponding to the electron emission source; and an anode voltage applied thereto; A display device maintained in a vacuum,
A glass substrate is attached to the cathode substrate via a sealing portion, and a high voltage introduction terminal for supplying the anode voltage is sealed to the glass substrate, and the anode substrate and the high voltage introduction terminal are connected to the cathode substrate. A connection member for conducting electrical connection is connected, and the connection member is connected to a plate-shaped metal anode terminal installed on the anode substrate, and the metal anode terminal is bonded to the anode substrate by conductive frit glass. A display device.   The display device according to claim 14, wherein the metal anode terminal is formed of a disk-shaped Fe—Ni alloy.   15. The display device according to claim 14, wherein the metal anode terminal is made of an alloy of Fe 52 wt% -Ni 48 wt%.   The display device according to claim 14, wherein the conductive frit glass is bonded to a frit glass mainly composed of vanadium oxide by a film in which silver particles and silver flakes are dispersed.   15. The display device according to claim 14, wherein the metal anode terminal is formed on a metal back made of an Al film formed on the anode substrate.   The display device according to claim 14, wherein the connection member is a metal contact spring.   15. The display device according to claim 14, wherein the conductive frit glass is bonded to a frit glass containing no lead as a component by a film in which silver particles and silver flakes are dispersed.

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