JP2009059601A - Image display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an FED (field emission display) that can supply an anode substrate with anode voltage as high voltage with high reliability, with voltage-withstanding characteristics improved. <P>SOLUTION: Supply of high voltage to the anode substrate 2 is carried out through a contact spring 50 connected to a high-voltage lead-in terminal 60. The high-voltage lead-in terminal 60 is installed on a high-voltage lead-in substrate 6 fitted to a cathode substrate 1. The contact spring 50 comes in contact with the anode substrate 2 through a through-hole 10 formed at the cathode substrate 1. A distance between the contact spring 50 and the through-hole 10 of the cathode substrate 1 is to be 1.5 mm or more to enable to greatly reduce generation of spark inside the FED. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

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

  Development of a so-called field emission display (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. Yes. The FED forms an image when electrons from an electron emission source strike a phosphor and emits light. In the future, brightness, contrast, moving image characteristics, etc. can provide excellent performance similar 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 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 the FED, the cathode substrate and the anode substrate face each other with a gap of about 2.8 mm, and a high electric field is formed. Therefore, sparks are likely to occur inside the FED. When a spark is generated, a part of many electron sources formed in a matrix is destroyed. This means that a part of the image is defective, which is a serious problem.

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

  The present invention supplies a high voltage to the anode substrate by connecting a contact spring to a high voltage introduction terminal formed on the cathode substrate and bringing the contact spring into contact with an anode terminal formed on the anode substrate. Although a high voltage is applied to the contact spring, the risk of spark is drastically reduced by setting the relationship between the contact spring and the internal element of the FED to a specific value.

  The present invention further reduces the risk of sparks caused by the anode substrate by appropriately setting the shape of the anode electrode formed on the anode substrate, specifically, the shape of the metal back. The specific configuration is as follows.

(1) A data signal line extending in the first direction and disposed in the second direction, a scanning line extending in the second direction and disposed in the first direction, and the data signal line And a cathode substrate on which an electron source is formed in the vicinity of the intersection of the scanning line, a phosphor is disposed in a portion corresponding to the electron source, a black matrix is formed between the phosphor and the phosphor, and the phosphor And an anode substrate on which a metal back is formed to cover the body and the black matrix, a spacer is formed between the cathode substrate and the anode substrate, and a periphery of the cathode substrate and the anode substrate is used with a sealing frame The cathode substrate is provided with a high voltage introduction substrate to which a high voltage introduction terminal is attached, and a contact spring is attached to the high voltage introduction terminal. The contact spring is connected to the anode substrate through a hole formed in the cathode substrate, and a distance between the contact spring and an end of the hole formed in the cathode substrate is 1.5 mm or more. A display device characterized by being made.
(2) The display device according to (1), wherein the distance between the contact spring and the electron source is 10 mm or more.
(3) The display device according to (1), wherein a distance of 6.5 mm or more is secured between the contact spring and the data signal line or the scanning line.
(4) The display device according to (1), wherein the distance between the contact spring and the sealing frame is 5 mm or more.
(5) The display device according to (1), wherein a distance between the contact spring and the spacer is 10 mm or more.

  (6) A data signal line extending in the first direction and disposed in the second direction, a scanning line extending in the second direction and disposed in the first direction, and the data signal line And a cathode substrate on which an electron source is formed in the vicinity of the intersection of the scanning line, a phosphor is disposed in a portion corresponding to the electron source, a black matrix is formed between the phosphor and the phosphor, and the phosphor And an anode substrate on which a metal back is formed to cover the body and a black matrix, a spacer is formed between the cathode substrate and the anode substrate, and a sealing frame is used around the cathode substrate and the anode substrate. The cathode substrate is provided with a high voltage introduction substrate to which a high voltage introduction terminal is attached, and a contact spring is attached to the high voltage introduction terminal. Lighted, the contact spring is connected to the anode substrate through the holes formed in the cathode substrate, the distance between the electron source and the contact spring display device characterized in that it is secured over 10 mm.

(7) a cathode substrate in which an electron emission source is formed in a matrix, a display area facing the cathode substrate, an anode voltage is applied, and a phosphor is formed at a location corresponding to the electron emission source; A display device comprising an anode substrate having a peripheral region surrounding a display region, the interior of which is maintained in a vacuum, wherein a black matrix and a metal back are formed in the peripheral region, and a peripheral edge of the metal back Has a curvature shape (hereinafter referred to as a corner R), and the corner R of the metal back has a curvature radius of 0.5 mm or more.
(8) The display device according to (7), wherein the corner R has a radius of curvature of 1 mm or more.

(9) a cathode substrate in which an electron emission source is formed in a matrix, a display area facing the cathode substrate, an anode voltage is applied, and a phosphor is formed at a location corresponding to the electron emission source; A display device comprising an anode substrate having a peripheral region surrounding a display region, the interior of which is maintained in a vacuum, wherein a black matrix and a metal back are formed in the peripheral region, and a peripheral edge of the black matrix Has a curvature shape (hereinafter referred to as a corner R), and the corner R of the black matrix has a curvature radius of 0.5 mm or more.
(10) The display device according to (9), wherein the corner R of the black matrix has a radius of curvature of 1 mm or more.

(11) A cathode substrate in which electron emission sources are formed in a matrix, a display area facing the cathode substrate, an anode voltage is applied, and a phosphor is formed at a location corresponding to the electron emission source; A display device comprising an anode substrate having a peripheral region surrounding a display region, the inside of which is maintained in a vacuum, wherein a black matrix and a metal back are formed in the peripheral region, and the periphery of the black matrix and the metal back Is formed with a curvature shape (hereinafter referred to as a corner R), and the corner R of the high resistance film has a radius of curvature of 0.1 mm. A display device characterized by being 5 mm or more.
(12) The display device according to (11), wherein the corner R of the high resistance film has a curvature radius of 1 mm or more.
(13) The display device according to (11), wherein the high resistance film is formed of iron oxide.
(14) The display device according to (11), wherein the high resistance film is formed over the entire circumference of the peripheral portion.

  According to the present invention, since the anode potential is supplied from the cathode substrate side to the anode substrate side using the contact spring, the anode voltage can be supplied with high reliability. Furthermore, the spark between the contact spring and the structure in the FED can be drastically reduced, and the reliability of the FED can be increased.

  Further, according to the present invention, it is possible to suppress a spark caused by a metal back or black matrix formed around the display region of the anode substrate, and improve the reliability of the FED.

  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. In FIG. 1, an anode substrate 2 is installed on a cathode substrate 1 via a sealing portion 3. On the cathode substrate 1, 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 system, SID system, and Spindt system have been developed, and any electron emission source is applicable 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 2, red, green, and blue phosphors that emit light by projecting an electron beam are formed corresponding to the electron emission sources. A black matrix (BM) is formed around the phosphor to improve image contrast. A metal back made of Al is formed so as to cover 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 21 by the electron beam, the electron beam must have a certain amount of energy, so 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 1 side, and a high voltage is supplied to the anode substrate 2 via a contact spring. In FIG. 1, an anode terminal 24 where the contact spring contacts the anode substrate 2 is formed at the upper right corner of the display device. Since the inside of the display device must be kept in a vacuum, an exhaust hole 81 for exhaust is formed in the lower right corner of the display device in FIG.

  FIG. 2 is a side view of FIG. 1 viewed from the C 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, a high voltage introduction substrate 6 for attaching the exhaust pipe 8 or the high voltage introduction terminal 60 is attached. The high voltage introduction substrate 6 is attached to the cathode substrate 1 via the high voltage introduction substrate sealing portion 7. In FIG. 2, an exhaust pipe 8 for evacuating the inside of the display device is drawn on the high voltage introduction substrate 6 in a state where the chip is turned off.

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 1 side and to the metal back 23 on the anode substrate 2 side by the fixing material 41. The spacer 4 is given a conductivity of about 10 ⁹ to 10 ¹¹ 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 2 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 onto the electron beam, and an image is displayed. It is formed. 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. Chromium oxide is formed on the anode substrate 2 side, and chromium is formed thereon. 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.

  4 is a cross-sectional view taken along the line BB of FIG. In FIG. 4, a through hole 10 is formed in the cathode substrate 1, and a high voltage is supplied to the anode substrate 2 by the contact spring 50 through the through hole 10. A chamfer 101 is formed at the end of the through hole 10. This is to prevent generation of glass dust and improve the withstand voltage. A high voltage introduction substrate 6 is installed through the high voltage introduction 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 a vacuum. The high voltage introduction 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 high-voltage introduction 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 high-voltage introducing substrate 6 have the same thickness. The thickness can be set freely.

  A hole for sealing the high voltage introduction terminal 60 is formed in the high voltage introduction substrate 6, and a chamfer 101 is also formed on this hole. This is to prevent the generation of glass dust and improve the withstand voltage characteristics. The high voltage introduction terminal 60 is sealed to the high voltage introduction substrate 6 and is kept airtight from 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. In this embodiment, Fe is 52% and Ni is 48%. The external terminal 63 of the high voltage introduction terminal 60 is a terminal for applying a high voltage to the anode substrate 2 from the outside, and is connected to an external socket.

  A contact spring 50 is attached to the high voltage introduction terminal 60 by spot welding. The high voltage applied to the high voltage introduction terminal 60 by the contact spring 50 is introduced to the anode substrate 2 side. The contact spring 50 comes into contact with the anode substrate 2 by the appropriate pressing of the contact portion 53 at the tip by the spring force.

  An anode terminal 24 for contacting the contact spring 50 is formed on the anode substrate 2. Since a relatively large current flows through the anode terminal 24, reliability is important. In this embodiment, the structure near the anode terminal 24 is as follows. A BM 22 of chromium and chromium oxide is formed on the anode substrate 2, and a metal back 23 made of Al is formed so as to cover the BM 22. This is the same configuration as the effective surface of the screen. In this embodiment, a conductive film as the anode terminal 24 is formed on the metal back 23 with a thickness of 10 μm to 30 μm. 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 is obtained by dispersing silver particles having a diameter of 1 μm to several μm in an organic solvent having a high viscosity. After firing, the silver particles are connected to each other to have conductivity. In some cases, the conductive film should have some resistance. In such a case, the resistance can be adjusted by further mixing a paste for frit glass with a normal silver paste. Note that the material of the conductive film is not limited to silver paste, and Ni paste in which Ni particles are dispersed, Al paste in which Al particles are dispersed, and the like can also be used. A graphite film bonded with a binder can also be used. The graphite in this case is preferably graphite. The resistance of the graphite film can be adjusted, for example, by mixing bengara (iron oxide) with graphite.

  By forming the conductive film as thick as 10 μm to 30 μm, the contact spring 50 and the conductive film can be stably contacted. That is, in the case of a metal film, the contact spring 50 and the metal film are in point contact, and there is a danger that current concentrates on the point contact portion and the conductive film is destroyed. The conductive film and the contact spring 50 can have a large contact area as compared with the case of a metal film, become a state close to surface contact, and stabilize the contact. Further, in the case of the conductive film as in the present embodiment, since the resistance is larger than that of metal, it is possible to prevent a large current from flowing through the contact portion 53. Also from this point, the stability of conduction by contact can be improved.

  FIG. 5 is a perspective view showing a state where the high voltage introduction terminal 60 and the contact spring 50 are connected by spot welding. In FIG. 5, a high voltage introduction terminal 60 includes a flat portion 61 where the contact spring 50 is spot-welded, a flange 62 sealed with a sealing material 32 on the high voltage introduction substrate 6, and an external terminal connected to an external power source. 63.

  FIG. 6 shows the shape of the contact spring 50 in this embodiment. The contact spring 50 is made of Inconel, which can be easily spot welded with the Fe—Ni alloy. The contact spring 50 includes a base portion 51 that is connected to the high voltage introduction terminal 60, an arm portion 52 that applies a spring force, and a contact portion 53 that is connected to the anode terminal 24 of the anode substrate 2.

  The contact portion 53 of the contact spring 50 comes into contact with the anode terminal 24 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, which is a material of the contact spring 50, has an appropriate spring force and has heat resistance. In the FED, heat resistance is an important problem because it undergoes a heat process at 400 ° C. or higher in a frit glass sealing process, an exhaust process, and the like. The thickness of Inconel in this embodiment is 0.09 mm in order to give an appropriate spring force. The material of Inconel is 0.1 mm. As will be described later, the contact spring 50 is chemically polished to a thickness of 0.09 mm.

  As shown in FIG. 4, a high voltage of 8 KV to 10 KV is applied to the contact spring 50. The distance between the cathode substrate 1 and the anode substrate 2 is about 2.8 mm, and the display device has a strong electric field. Further, the contact spring 50 is in contact with the anode substrate 2 through the through hole 10 formed in the cathode substrate 1. Further, the tip of the contact portion 53 of the contact spring 50 is closer to the cathode substrate 1 than the metal back 23 and the like formed on the anode substrate 2. Thus, the contact spring 50, particularly the contact portion 53, is exposed to severe conditions in terms of withstand voltage.

  As described above, since a large electric field is applied to the contact spring 50, the shape of the contact spring 50 is important. In spite of the fact that the contact spring 50 is on the high voltage side, it has been observed that when a sharp edge is present in the contact spring 50, particularly the contact portion 53, sparks are generated from this portion. As shown in FIG. 6, the present invention prevents sparks by forming R at the corner portion of the tip of the contact spring 50, particularly in the contact portion 53.

  FIG. 7 is a detailed view of the contact spring 50 in this embodiment. 7A is a plan view of the contact spring 50, FIG. 7B is a front view, FIG. 7C is a back view, and FIG. 7D is a side view. In FIG. 7A, by forming R at the tip of the contact portion 53, sharp edges can be prevented and the withstand voltage characteristics can be improved. The width B of the contact portion 53 in FIG. 7A is 2 mm. The withstand voltage characteristic is greatly improved by setting the curvature radius R of the tip of the contact portion 53 in FIG. 7A to 0.2 mm or more, preferably 0.5 mm or more. By setting the curvature radius R of the tip to 1.0 mm or more, a more preferable result with respect to the withstand voltage can be obtained.

  The withstand voltage can be improved by providing the tip of the base 51 shown in FIG. The radius of curvature RB of the corner portion of the base portion 51 is about 1.2 mm. The width BB of the base portion 51 of the contact spring 50 is slightly larger than the width B of the arm portion 52 and is 2.35 mm. By forming the RB in the base portion 51, it is possible to prevent the tip portion from being deformed, which is advantageous in terms of withstand voltage.

  In FIG.7 (b), the front-end | tip of the contact part 53 of the contact spring 50 is a spherical surface, and the curvature radius RC is 2 mm. The radius of curvature RC of the contact portion 53 is set in consideration of the contact area with the anode terminal 24, the contact pressure with the anode terminal 24 due to the spring force of the arm portion 52 of the contact spring 50, and the like. The contact portion 53 has a horizontal diameter D of 3.4 mm. When the contact spring 50 comes into contact with the anode terminal 24, the arm portion 52 is bent, and D shown in FIG. The plate thickness t of the material of the contact spring 50 is 0.1 mm, but finally becomes 0.09 mm by chemical polishing.

  In FIG.7 (c), the diameter DB of the horizontal direction of the base part 51 is 3.1 mm. The curvature radii at the tips of the base portion 51 and the contact portion 53 are as described with reference to FIG.

  In FIG.7 (d), the height of the contact spring 50 is 14 mm. When the contact spring 50 is inserted into the FED, the arm portion 52 of the contact spring 50 is bent, and L1 becomes small. The reason why the arm portion 52 is divided into two is to increase the reliability of contact. The arm portion 52 has a width B of 2 mm and a length L2 of 11 mm. The spring force is determined by the length L2 and the width B of the arm portion 52.

  FIG. 8 is an enlarged view of a corner portion of the cathode substrate 1 where the contact spring 50 is inserted through the through hole in the cathode substrate 1. In FIG. 8, the contact spring 50 is shown in a plan view seen from above. Inside the cathode substrate 1, a frame member 31 for sealing with the anode substrate 2 is installed via a sealing material 32. The distance between the cathode plate and the anode plate is 2.8 mm. The inside of the frame member 31 is evacuated to a vacuum.

  In FIG. 8, a large number of data signal lines 12 extend in the vertical direction of the screen. The data signal line 12 penetrates under the frame member 31 and extends to the outside, and takes in a data signal from the outside. In FIG. 8, a large number of scanning lines 11 extend in the horizontal direction of the screen. The scanning line 11 penetrates under the frame member 31 and extends to the outside to capture a scanning signal. An insulating layer is formed between the data signal line 12 and the scanning line 11.

  A through hole 10 is formed in an inner corner portion of the frame member 31, and a contact spring 50 is inserted through the through hole and contacts an anode terminal formed on an anode substrate (not shown). The diameter of the through hole in this embodiment is 10 mm. A chamfer 101 is formed in the through hole. A high voltage of 8 to 10 KV, which is an anode voltage, is applied to the contact spring 50. On the other hand, the voltage applied to the data signal line 12 or the scanning line 11 formed on the cathode substrate 1 is very small, and is closer to the ground potential than the anode voltage. Therefore, a strong electric field is applied between the contact spring 50 and each element formed on the cathode substrate 1, and spark is likely to occur.

  A portion of the cathode substrate 1 where the data signal line 12 or the scanning line 11 is not formed is a glass surface or an insulating film surface. The surface of the insulator is easily charged and the potential is unstable, and a spark is easily generated between the surface of the insulator and the contact spring 50. In particular, since electrons are emitted from the electron source 13 during the FED operation, the problem of sparks due to the influence of charging is serious. Further, the periphery of the through hole 10 through which the contact spring 50 is inserted is also an insulating surface, and the risk of sparking is great. However, the spark around the contact spring 50 and the through hole can be drastically reduced by securing the distance A between the contact spring 50 and the through hole end portion shown in FIG. Enlarging the through hole is a problem due to the mechanical strength of the FED. On the other hand, making the contact spring 50 extremely small has a limit in contact with the anode of the contact spring 50 in terms of reliability. As described above, the fact that the spark can be drastically reduced by securing a distance of 1.5 mm is very important for realizing the FED.

  In the FED, an electron source 13 is formed in the vicinity of the data signal line 12 and the scanning line 11. The potential of the electron source 13 is the same as that of the scanning line 11. The potential of the scanning line 11 is usually small enough to be ignored as compared with the anode potential. Therefore, normally, the potential difference between the electron source 13 and the contact spring 50 is the same as the anode voltage. If a spark is generated by the electron source 13 and the contact spring 50, the electron source 13 is destroyed, and a part of the FED screen becomes defective. Therefore, it is necessary to avoid the spark between the electron source 13 and the contact spring 50 as much as possible. When the distance B between the contact spring 50 and the electron source 13 shown in FIG. 13 is 10 mm or more, the spark between the electron source 13 and the contact spring 50 can be made substantially zero. Considering that the distance between the anode substrate 2 and the cathode substrate 1 is 2.8 mm, 10 mm is a large value. However, securing such a large value is necessary for suppressing the spark between the contact spring 50 and the electron source 13. This embodiment is important in that it is necessary to define the distance from the electron source 13 directly.

  A data signal is applied to the data signal line 12 and a scanning signal is applied to the scanning line 11. Both signals are substantially close to the ground potential as compared with the anode voltage. Therefore, a spark between the data signal line 12 and the scanning line 11 is also a big problem. By experiment, the distance C between the contact spring 50 and the data signal line 12 or the scanning line 11 is set to 6.5 mm or more, so that the spark between the contact spring 50 and the data signal line 12 or the scanning line 11 can be drastically reduced. .

  A frame member 31 that seals the cathode substrate 1 and the anode substrate 2 and secures the distance between the cathode substrate 1 and the anode substrate 2 is also formed of an insulator, generally glass. Therefore, the frame member 31 is also charged during the FED operation. Since the frame member 31 is an insulator, the charged state of the surface is unstable. Therefore, a spark is easily generated between the contact spring 50 and the contact spring 50. On the other hand, if the through hole is arranged near the frame member 31 and the contact spring 50 is also arranged near the frame member 31, the display area of the FED can be expanded. However, when the contact spring 50 is disposed close to the frame member 31, a spark is generated between the contact spring 50 and the frame member 31. By ensuring D in FIG. 8 which is the distance between the contact spring 50 and the frame member 31 to be 5 mm or more, the spark between the contact spring 50 and the frame member 31 can be made substantially zero. Considering that the distance between the anode substrate 2 and the cathode substrate 1 is 2.8 mm, 5 mm is a large value. However, securing such a large value is necessary for suppressing sparks between the contact spring 50 and the frame member 31.

  In the FED, a spacer 4 is used to maintain the distance between the cathode substrate 1 and the anode substrate 2 against atmospheric pressure. The spacer 4 is installed on the scanning line so as to prevent the image formation. In order to prevent the spacer 4 from being charged, a slight conductivity is given to the spacer surface, and a slight current flows through the spacer 4 during the FED operation. Therefore, the anode side of the spacer 4 is almost at the anode potential, and the cathode side is at the potential of the scanning line 11, which is almost the ground potential as compared with the anode potential. Therefore, the potential difference with the contact spring 50 is the largest on the cathode side of the spacer 4. In the present embodiment, the spark between the contact spring 50 and the spacer can be made substantially zero by setting the distance between the contact spring 50 and the spacer 4 to 10 mm or more, particularly on the cathode side.

  On the other hand, as shown in FIG. 7, the contact spring 50 has a corner R so as not to form a sharp edge at the tip of the contact spring, or a chemical polishing is applied to the contact spring 50 so as not to form a sharp edge at the end. I have to. With such a configuration, the spark between the contact spring 50 and the surrounding structure can be suppressed.

  FIG. 9 shows a modification of the first embodiment. In FIG. 9, not only the high voltage introduction terminal 60 but also the exhaust hole 81 and the exhaust pipe 8 are attached to the high voltage introduction substrate 6. The inside of the FED is exhausted through the through hole of the cathode substrate 1. The exhaust pipe 8 in FIG. 9 shows a state in which the chip is turned off after the exhaust. Other configurations are the same as those in FIG. Even in the configuration as shown in FIG. 9, the relationship between the contact spring 50 and the surrounding structures can be reduced drastically by adopting the configuration described above.

  The first embodiment discloses a configuration that suppresses sparks between the contact spring 50 and the surrounding structure. On the other hand, the anode substrate 2 can also cause a spark. Most of the anode substrate 2 is a display area 100 in which a phosphor 21 and the like are formed, but a BM 22 or a metal back 23 extends around the display area 100. The configuration of the anode substrate 2 in the layer direction is as described in FIG. In the second embodiment, sparks are prevented by the planar configuration of the anode substrate 2.

  FIG. 10 is a plan view of the inside of the anode substrate 2. In FIG. 10, a BM 22 and a metal back 23 are formed in a frame shape around the display area 100. In this embodiment, since it is assumed that the BM 22 and the metal back 23 are formed in the same region, only the metal back 23 is shown in FIG. If the BM 22 is formed to the outside of the metal back 23, the following description should be read as BM 22 instead of the metal back 23.

  In FIG. 10, the metal back 23 projects to the vicinity of the sealing portion 3 in the upper right to make contact with the contact spring 50. An anode terminal is formed on the metal back 23 protruding to the upper right corner. The configuration of the anode terminal is as described in the first embodiment. The periphery of the metal back is an insulating glass surface. The glass surface is charged and the potential becomes unstable during operation. A sealing portion 3 for sealing with the cathode substrate 1 is formed around the metal back 23.

  FIG. 11 shows the configuration of the upper right corner of FIG. 10 according to the conventional configuration. In FIG. 11, an anode terminal 24 is formed on a metal back 23 projecting from a corner portion. As shown in FIG. 11, the corner portion of the metal back 23 has a sharp corner. When such a corner portion is formed on the metal back 23, a spark is generated between the peripheral charged glass portion and the metal back 23. Conventionally, it has been thought that the cause of the spark is a sharp edge on the cathode side. However, in a display device driven by electrons, such as an FED, since the glass surface is charged, the sharp edge on the anode side also affects the spark.

  In this embodiment, the sparks caused by the metal back 23 are prevented by forming R at the peripheral corners of the metal back 23. FIG. 12 is a view showing the shape of the metal back 23 according to this embodiment. FIG. 12A is an upper right part A of FIG. 12B is an upper left B portion of FIG. 10, FIG. 12C is a lower left C portion of FIG. 10, and FIG. 12D is an enlarged view of the lower right portion of FIG. As shown in FIG. 12, REs, which are all corners R, are formed at the corners of the metal back 23. The value of RE is 0.5 mm or more, preferably 1 mm or more. The RE is preferably formed not only at the edge portion near the anode terminal 24 but also at all corner edge portions formed around the metal back as shown in FIG.

  The metal back 23 is formed by sputtering or vapor deposition. The corner edge RE as shown in FIG. 12 can be formed by appropriately setting a sputtering or vapor deposition mask.

  In the above description, the metal back 23 is the same as the BM 22 or the metal back 23 is formed outside the BM 22. However, when the BM 22 is formed outside the metal back 23, the RE, which is the R of the corner edge portion of the BM 22, may be 0.5 mm or more, preferably 1 mm or more. The BM 22 has a two-layer structure of chromium and chromium oxide, and the chromium oxide is covered with chromium. Since the shape of the BM 22 is formed by photoetching, it is easy to form R at the corner.

  FIG. 13 shows a third embodiment of the present invention. The metal back 23 is formed of aluminum which is a metal. In the example of FIG. 12, since the end of the metal film is adjacent to the glass surface, the surface resistance changes drastically. When the glass surface is charged, the potential difference with the metal back 23 becomes unstable, which becomes a starting point of spark.

  In this embodiment, as shown in FIG. 13, iron oxide (Bengara), which is a high resistance film 25, is applied around the metal back. In such a configuration, the surface resistance gradually changes between the metal back 23 and the glass. Then, even if the glass is charged during the FED operation, the electric field at the end of the metal back is relaxed by the high resistance film 25, and the spark is suppressed.

  In this case, the electric field tends to concentrate on the end portion of the high resistance film 25 in relation to the charged portion of the glass. In this embodiment, the corner portion of the high resistance film 25 has a curvature like a radius RB, and the electric field concentration is alleviated. The value of RB is 0.5 mm or more, preferably 1 mm or more. The high resistance film 25 is best formed over the entire circumference of the metal back. If it is difficult to apply the high resistance film 25 over the entire circumference, the effect can be improved even if it is applied only to the region shown in FIG.

  Application of the high resistance film 25 can be performed by screen printing. According to screen printing, it is easy to form an R of about 0.5 mm at the corner. The above configuration has been described on the assumption that the metal back 23 is the same region as the BM 22 or the metal back 23 is wider. When the range of the BM 22 is wider than that of the metal back 23, the above description may be replaced with the BM 22 instead of the metal back 23.

  As described above, according to the present embodiment, the spark is prevented by the high resistance film 25 and the occurrence of the spark is prevented by forming the curvature radius RB at the corner portion of the high resistance film 25 as well. I can do it.

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 perspective view of a high voltage introduction terminal and a contact spring. It is a perspective view of a contact spring. It is detail drawing of a contact spring. It is an enlarged plan view near the corner of the cathode substrate. It is sectional drawing which shows the other form of Example 1. It is an inner side top view of an anode substrate. It is an enlarged plan view of the inner corner portion of the anode substrate. 6 is an enlarged plan view of an anode substrate inner corner portion of Example 2. FIG. 6 is an enlarged plan view of an anode substrate inner corner portion of Example 3. FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Cathode substrate, 2 ... Anode substrate, 3 ... Sealing part, 4 ... Spacer, 5 ... Terminal, 6 ... High voltage introduction board, 7 ... High voltage introduction Substrate 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 (anode electrode), 24 ... Anode terminal, 25 ... High resistance film, 31 ... Frame member, 32 ... Sealing material, 50 ... Contact spring, 51 ... Contact spring base, 52 ... Contact spring arm, 53 ... Contact spring contact, 60 ... High voltage introduction terminal, 61 ... High voltage introduction Flat part of the terminal, 62... Parts, external terminals 63 ... high-voltage introduction terminal, 81 ... exhaust holes 100 ... display area, 101 ... chamfered.

Claims (14)

A data signal line extending in the first direction and arranged in the second direction, a scanning line extending in the second direction and arranged in the first direction, the data signal line and the scanning A cathode substrate on which an electron source is formed in the vicinity of the intersection with the line, a phosphor is disposed in a portion corresponding to the electron source, and a black matrix is formed between the phosphor and the phosphor. An anode substrate having a metal back covering the matrix, a spacer is formed between the cathode substrate and the anode substrate, and a periphery of the cathode substrate and the anode substrate is sealed using a sealing frame And a display device in which the inside is kept in vacuum,
A high voltage introduction substrate having a high voltage introduction terminal attached thereto is attached to the cathode substrate, a contact spring is attached to the high voltage introduction terminal, and the contact spring passes through a hole formed in the cathode substrate. Connected to the anode substrate,
A distance between the contact spring and the end of the hole formed in the cathode substrate is secured to 1.5 mm or more.   The display device according to claim 1, wherein a distance between the contact spring and the electron source is 10 mm or more.   The display device according to claim 1, wherein a distance of 6.5 mm or more is secured between the contact spring and the data signal line or the scanning line. The display device according to claim 1, wherein a distance between the contact spring and the sealing frame is 5 mm or more.
  The display device according to claim 1, wherein a distance between the contact spring and the spacer is 10 mm or more. A data signal line extending in the first direction and arranged in the second direction, a scanning line extending in the second direction and arranged in the first direction, the data signal line and the scanning A cathode substrate on which an electron source is formed in the vicinity of the intersection with the line, a phosphor is disposed in a portion corresponding to the electron source, and a black matrix is formed between the phosphor and the phosphor. An anode substrate having a metal back covering the matrix, a spacer is formed between the cathode substrate and the anode substrate, and a periphery of the cathode substrate and the anode substrate is sealed using a sealing frame And a display device in which the inside is kept in vacuum,
A high voltage introduction substrate having a high voltage introduction terminal attached thereto is attached to the cathode substrate, a contact spring is attached to the high voltage introduction terminal, and the contact spring passes through a hole formed in the cathode substrate. Connected to the anode substrate,
A distance between the contact spring and the electron source is 10 mm or more. A cathode substrate in which an electron emission source is formed in a matrix, a display region facing the cathode substrate, an anode voltage is applied, and a phosphor is formed at a location corresponding to the electron emission source, and the display region A display device comprising an anode substrate having an enclosed peripheral region, the inside of which is maintained in a vacuum,
A black matrix and a metal back are formed in the peripheral region, and a corner R is formed at a peripheral end of the metal back, and the corner R of the metal back has a radius of curvature of 0.5 mm or more. A display device characterized by that.   The display device according to claim 7, wherein the corner R has a curvature radius of 1 mm or more. A cathode substrate in which an electron emission source is formed in a matrix, a display region facing the cathode substrate, an anode voltage is applied, and a phosphor is formed at a location corresponding to the electron emission source, and the display region A display device comprising an anode substrate having an enclosed peripheral region, the inside of which is maintained in a vacuum,
A black matrix and a metal back are formed in the peripheral region, and a corner R is formed at a peripheral end of the black matrix, and the corner R of the black matrix has a radius of curvature of 0.5 mm or more. A display device characterized by that.   The display device according to claim 9, wherein the corner R of the black matrix has a radius of curvature of 1 mm or more. A cathode substrate in which an electron emission source is formed in a matrix, a display region facing the cathode substrate, an anode voltage is applied, and a phosphor is formed at a location corresponding to the electron emission source, and the display region A display device comprising an anode substrate having an enclosed peripheral region, the inside of which is maintained in a vacuum,
A black matrix and a metal back are formed in the peripheral region, a high resistance film is formed around the black matrix and the metal back, and a corner R is formed at a peripheral edge of the high resistance film. And the corner R of the high resistance film has a radius of curvature of 0.5 mm or more.   The display device according to claim 11, wherein the corner R of the high resistance film has a curvature radius of 1 mm or more.   The display device according to claim 11, wherein the high resistance film is formed of iron oxide.   The display device according to claim 11, wherein the high resistance film is formed over the entire circumference of the peripheral portion.

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