JP2009134929A - Display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent an electron source from being broken by a spark current when a spark is generated in an FED. <P>SOLUTION: A large number of stripe-like metal back units 231 are formed on the inside of an anode substrate 2. A high voltage supplied from an anode terminal 24 passes through a metal back peripheral part 233 and supplied to the stripe-like metal back units 231 through resistors 232. A BM 22 made of a glass material having a vanadium oxide having very high resistance is formed between the stripe-like metal back units 231. Accordingly, even if a spark is generated, since a current flowing mainly becomes charges charged in the stripe-like metal back unit 231, the spark current can be reduced. As a result, an electron source can be prevented from being broken by the spark. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a flat display device in which the inside is evacuated, electron emission sources are arranged in a matrix on the back substrate, and phosphors corresponding to the front substrate are arranged. Related.

  A field emission display (FED) is a display device in which an inside sandwiched between two glass substrates is evacuated, electron emission sources are arranged in a matrix on one substrate, and phosphors are arranged on a counter substrate. 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. Since a high voltage of about 10 KV is applied between the anode substrate on which the phosphor screen is formed and the cathode substrate on which the electron source is formed, a considerably high electric field is formed inside the display device. Accordingly, sparks are likely to occur between the anode substrate and the cathode substrate.

  A large number of electron sources are formed in a matrix on the cathode substrate. Although many sparks occur between the anode substrate and the cathode substrate, when a spark current flows through the electron source formed on the cathode substrate, the electron source is destroyed. Various types of FED electron sources such as MIM type, SED type, Spindt type, and carbon nanotube type have been developed, but it is common to all electron sources to be destroyed by sparks.

  Although it is best to have a structure that does not generate sparks in the FED, it is difficult to make the sparks zero because a high electric field is formed in the FED. Therefore, even if a spark occurs, if the spark current can be suppressed to a level that does not destroy the electron source, the FED can be prevented from being destroyed.

  The spark current often flows into the cathode substrate from a metal back formed on the anode substrate to which a high voltage is applied. “Patent Document 1” describes a technique for suppressing a spark current by installing a high resistance between a high-voltage power supply line and a metal back. “Patent Document 1” also discloses a technique for suppressing the spark current by dividing the metal back into units and suppressing the current flowing to the cathode substrate only to the discharge of the electric charge charged to each unit when a spark occurs. Is also described.

JP 2004-273376 A

  The technique described in “Patent Document 1” is a technique for suppressing a spark current to only a discharge current from each unit when a spark is generated by dividing a metal back into units. In this case, it is difficult to suppress the spark discharge current unless the electrical insulation between adjacent units is sufficient. In “Patent Document 1”, a partition is formed between the phosphors. A black matrix (BM) is formed between the partition walls and the anode substrate which is a glass substrate. “Patent Document 1” does not describe the material of the partition walls.

  In addition, when dividing the metal back into units, the discharge current can be reduced by increasing the number of divisions and reducing the area of each unit. However, Patent Document 1 discloses a technique for finely dividing the metal back. Is not described. Therefore, it is difficult to reduce the spark current practically only by the technique described in “Patent Document 1”.

  The present invention has been made in order to solve the above-described conventional problems. By making the material of BM formed between the phosphors an insulator or a very large resistance, the metal back can be divided. The spark current due to is substantially reduced. Further, the present invention makes it possible to divide the metal back into a large number of units by dividing the vapor deposition of the metal back into a plurality of times, and to reduce the spark current. The specific configuration is as follows.

  (1) A display device comprising a cathode substrate in which an electron source is formed in a matrix, and an anode substrate facing the cathode substrate and having an effective screen formed by forming a phosphor at a location corresponding to the electron source. The phosphor has a horizontal pitch and a vertical pitch, a black matrix is formed between the phosphors, and a horizontal voltage is applied across the phosphor and the black matrix. A plurality of long striped metal backs are formed, the plurality of striped metal backs are separated from each other on the black matrix, and an anode voltage is applied to the metal back around the striped metal back. The peripheral portion for supplying is formed of the same material as the metal back, and the striped metal back and the periphery are provided. The parts are connected by resistors, the black matrix display characterized in that it is formed of a glass material mainly composed of vanadium oxide device.

  (2) The display device according to (1), wherein a width of the stripe-shaped metal back is smaller than a vertical pitch of the phosphor.

  (3) The display device according to (1), wherein a width of the striped metal back is smaller than five times a vertical pitch of the phosphor.

(4) The display device according to (1), wherein the glass material mainly composed of vanadium oxide has a resistivity of 10 ⁸ Ωcm or more.

  (5) The display device according to (1), wherein the black matrix is a glass material containing vanadium oxide in an amount of 30% to 40%.

  (6) The display device according to (1), wherein the peripheral portion has a ring shape surrounding the effective screen.

  (7) The display device according to (1), wherein the resistors are formed on the left and right sides of the screen.

  (8) The display device according to (1), wherein the resistor is made of graphite.

  (9) A display device comprising: a cathode substrate in which an electron source is formed in a matrix; and an anode substrate facing the cathode substrate and having a phosphor formed at a location corresponding to the electron source to form an effective screen. The phosphor has a horizontal pitch and a vertical pitch, a black matrix is formed between the phosphors, and a horizontal voltage is applied across the phosphor and the black matrix. A plurality of long striped metal backs are formed, the plurality of striped metal backs are separated from each other on the black matrix, and an anode voltage is applied to the metal back around the striped metal back. The peripheral portion for supplying is formed of the same material as the metal back, and the striped metal back and the periphery are provided. Parts are connected by the resistor and a display device, characterized in that the black matrix is formed by diamond-like carbon.

  (10) The display device according to (9), wherein a width of the stripe-shaped metal back is smaller than a vertical pitch of the phosphor.

  (11) The display device according to (9), wherein a width of the striped metal back is smaller than five times a vertical pitch of the phosphor.

(12) The display device according to (9), wherein the diamond-like carbon has a resistivity of 10 ¹⁰ Ωcm or more.

  (13) The display device according to (9), wherein the peripheral portion has a ring shape surrounding the effective screen.

  (14) The display device according to (9), wherein the resistors are formed on the left and right sides of the screen.

  (15) The display device according to (9), wherein the resistor is made of graphite.

  (16) A display device comprising: a cathode substrate in which an electron source is formed in a matrix; and an anode substrate facing the cathode substrate and having an effective screen formed with a phosphor formed at a location corresponding to the electron source. The phosphor has a horizontal pitch and a vertical pitch, a black matrix is formed between the phosphors, and a horizontal voltage is applied across the phosphor and the black matrix. A plurality of long striped metal backs are formed, the plurality of striped metal backs are separated from each other on the black matrix, and an anode voltage is applied to the metal back around the striped metal back. The peripheral portion for supplying is formed of the same material as the metal back, and the plurality of striped metal backs Using different masks, a plurality of mask vapor deposition or the display device characterized by being formed by a mask sputtering.

  (17) The plurality of striped metal backs are formed by first mask vapor deposition using a first mask, or second mask vapor deposition using a mask sputtering and a second mask, or mask sputtering. And a pitch of slits for forming the stripe-shaped metal back formed on the first mask and a pitch of slits for forming the stripe-shaped metal back formed on the second mask. Is twice the pitch of the stripe-shaped metal back. The display device according to (16),

  (18) The plurality of stripe-shaped metal backs use a first mask, a first mask vapor deposition or mask sputtering, a second mask uses a second mask vapor deposition or mask sputtering, and Formed by third mask vapor deposition or mask sputtering using a third mask, and the pitch of slits for forming the stripe-shaped metal back formed on the first mask; The pitch of the slits for forming the striped metal back formed on the mask 2 and the pitch of the slits for forming the striped metal back formed on the third mask are the stripes. The display device according to (16), wherein the pitch is three times the pitch of the metal back.

According to the present invention, the metal back is finely divided into thin stripe units, and the black matrix is a glass material mainly composed of vanadium oxide having a high resistivity of 10 ⁸ Ωcm or more, or 10 ¹⁰ Ωcm or more. Since it is composed of diamond-like carbon having a resistivity of, it is possible to suppress sparks between adjacent units. Therefore, the amount of charge flowing into the cathode by the spark can be limited to the amount of charge for one unit of spark. As a result, the spark current can be substantially reduced.

  In addition, according to the present invention, the metal back is formed by a plurality of times of mask vapor deposition or mask sputtering using different masks, so that a very thin stripe-shaped metal back unit is formed on the entire effective surface of the anode substrate. Can effectively reduce the spark current.

  Furthermore, according to the present invention, a large number of stripe-shaped metal back units and the periphery of the same material surrounding the periphery are electrically connected by a resistor such as graphite, so that a highly reliable connection can be achieved. . Further, since the stripe-shaped metal back unit and the peripheral portion are connected at two locations, each unit is connected in parallel with the anode power feeding portion, and the voltage drop of the anode due to the cathode current can be suppressed.

  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. As an electron emission source, various types such as a so-called MIM method, SED method, Spindt method, and carbon nanotube have been developed. However, the present invention can be applied to any electron emission source.

  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.

  The spacer 4 is installed on the scanning line of this effective screen area. On the anode substrate 2, red, green, and blue phosphors 21 that emit light by an electron beam projection are formed corresponding to the electron emission sources. A black matrix (BM22) is formed around the phosphor 21 to improve image contrast. A metal back 23 made of Al is formed so as to cover the black matrix. A high voltage is applied to the metal back 23, 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, and therefore, a high voltage of 8 KV to 10 KV is applied to the metal back 23 of the anode substrate 2. In this embodiment, a high voltage introduction terminal 60 for supplying a high voltage from the outside is provided on the cathode substrate 1 side, and a high voltage is supplied to the anode substrate 2 through a contact spring. Since the inside of the display device must be kept in vacuum, an exhaust hole 81 and an exhaust pipe 8 are provided on the back side 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 a high voltage introduction terminal is attached. The exhaust substrate 6 is attached to the cathode substrate 1 through an exhaust substrate sealing portion. 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.

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 14 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 13. 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 on the scanning line by the frit glass 41 on the anode substrate 2 side and on the scanning line by the frit glass 41 on the cathode substrate 1 side. The spacer 4 is provided with a conductivity of about 10 ⁷ to 10 ¹¹ Ω · cm, preferably about 10 ⁸ to 10 ⁹ Ω · cm. The spacer 4 has a scanning line on the cathode substrate 1 side and a metal back 23 on the anode substrate 2 side. The spacer 4 is prevented from being charged by passing a slight current between them.

  In order to keep the inside of the display device in a vacuum, the anode substrate 2 and the sealing frame 31 are sealed with frit glass 32, and the cathode substrate 1 and the sealing frame 31 are sealed with frit glass 33. The bonding temperature of the frit glass 32 is higher than the bonding temperature of the frit glass 33.

  On the anode substrate 2 side, phosphors 21 such as red, green, and blue are arranged at locations corresponding to the electron emission sources 14, 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. 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.

  In FIG. 3, after the anode substrate 2 and the cathode substrate 1 are sealed through the sealing frame 31 and the frit glass, the inside of the FED is evacuated to a vacuum through the exhaust pipe. 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. In order to apply a high voltage of 8 KV to 10 KV at this narrow interval, a high electric field is formed inside the display device, and there is a danger of sparking. In order to prevent sparks, the spacer 4 and the frit glass to which the spacer 4 is fixed are provided with electrical conductivity to prevent the spacer 4 from being charged.

  FIG. 4 is a schematic view showing a CC cross section of FIG. In FIG. 4, data signal lines 12 extend in the horizontal direction on the cathode substrate 1. The scanning line 11 extends in the normal direction of the paper surface at right angles to the data signal line 12. An electron source 14 is disposed on the data signal line 12 between the scanning lines. The electron source 14 includes a data signal line 12 serving as a lower electrode and an upper electrode that is electrically connected to the scanning line 11 via a tunnel insulating film. In this embodiment, an MIM electron source is used as the electron source 14, but the present invention is not limited to the MIM electron source but can be applied to other electron sources.

  A phosphor 21 is formed on the anode substrate 2 and the space between the phosphor and the phosphor is covered with a BM 22. A metal back 23 is formed by sputtering Al over the phosphor 21 and the BM 22. An anode voltage that is a high voltage of about 8 KV to 10 KV is applied to the metal back 23. The electron beam emitted from the electron source 14 is accelerated by the anode voltage. The electron beam emitted from the electron source 14 penetrates the metal back 23 and strikes the phosphor 21 to cause the phosphor 21 to shine, thereby forming a color image. The electron beam spreads when emitted from the electron source 14, but is designed to be slightly larger than each phosphor on the phosphor screen.

  In order to maintain the distance between the anode substrate 2 and the cathode substrate 1, the spacer 4 is installed as described with reference to FIG. The spacer 4 is disposed between the scanning line 11 on the cathode substrate 1 and the metal back 23 on the anode substrate 2. At this position, the spacer 4 does not interfere with image formation.

  5 is a cross-sectional view taken along the line BB of FIG. In FIG. 5, 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 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 with the frit glass 32, and the exhaust substrate frame 71 is sealed with the cathode substrate 1 with the frit glass 33. In this embodiment, the frit glass 32 has a higher bonding temperature than the frit glass 33. 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 penetrates the exhaust board 6 while maintaining airtightness with the outside. The high voltage introduction terminal 60 is sealed with the exhaust substrate 6 by the frit glass 32.
An Fe—Ni alloy is used for the high voltage introduction terminal 60, but the ratio of Fe and Ni is determined in consideration of the thermal expansion of the exhaust substrate 6. In this example, Ni is 48%. An exhaust hole 81 is formed in the exhaust substrate 6, and an exhaust pipe 8 is sealed in the exhaust hole 81 via a frit glass 32. The inside of the display device is evacuated through the exhaust pipe 8, and then the exhaust pipe 8 is chipped off and the inside of the display device is kept in vacuum. FIG. 5 shows a state where the exhaust pipe 8 is chipped off.

  The frit glass 32 has a higher bonding temperature than the frit glass 33, and accordingly, the reliability of sealing the exhaust pipe and the high voltage introduction terminal is increased. In other words, since the exhaust pipe and the high voltage introduction terminal are sealed regardless of the baking of the cathode terminal on which the electron source is formed, the reliability of the sealing is increased by using frit glass having a high bonding temperature. ing.

  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 is formed on the anode substrate 2, and a metal back 23 made of Al is formed covering the BM 22. This is the same configuration as the effective screen 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 about 10 μm.

  In this embodiment, the anode terminal 24 is formed by applying a silver paste by printing and then baking it. There is no need to provide a special process for firing the anode terminal 24. For example, the anode terminal 24 may be performed simultaneously with the firing process when the spacer 4 is fixed.

  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.

  FIG. 6 is a plan view of the inside of the anode substrate 2 according to the conventional example. In FIG. 6, a sealing portion 3 is formed around the anode substrate 2. A metal back is formed to cover the display area where the phosphor is formed. The outer shape of the metal back and the BM 22 is the same. In the upper right corner of the metal back in FIG. 6, a power feeding part 235 for the anode terminal is formed. An anode terminal 24 is formed on the power feeding unit 235. A contact spring from the cathode substrate 1 side comes into contact with the anode terminal and a high voltage is supplied.

  FIG. 7 is a plan view of the inside of the anode substrate 2 showing the first embodiment of the present invention. In FIG. 7, a sealing portion 3 is formed around the anode substrate 2. The metal back is divided into a large number of striped metal back units 231. A BM 22 exists between the stripe-shaped metal back unit 231 and the stripe-shaped metal back unit 231. In FIG. 7, the width of the stripe-shaped metal back unit 231 is drawn thick for the sake of clarity, but is actually a thin one that is slightly smaller than the vertical pitch of the phosphor. An Al metal back peripheral portion 233 is formed so as to surround a large number of striped metal back units 231. The metal back peripheral part 233 and each stripe-shaped metal back unit 231 are connected by a resistor 232 at two places on the short side. The resistor 232 is made of a graphite-based material and has a high resistance value. This is to suppress the spark current. In FIG. 7, the metal back peripheral portion 233 has an annular shape, but is not limited to an annular shape, and may be any shape that can supply a high voltage from both sides of the screen to the striped metal back unit 231.

  The striped metal back units 231 are insulated from each other except the resistor 232. Further, the metal back peripheral portion 233 and each stripe-shaped metal back unit 231 are also insulated except for the resistor 232. When a high voltage is supplied from the power supply unit 235, the high voltage is supplied to the metal back peripheral part 233 as it is, and the high voltage is supplied to the striped metal back unit 231 via the resistor 232.

  A method of forming such an anode-side electrode will be described in detail in the second embodiment, but briefly described as follows. Specifically, first, Al stripe-backed metal back unit 231 and metal back peripheral portion 233 are formed by vapor-depositing Al. Thereafter, a resistor 232 made of graphite is applied to both sides by printing. The film thickness of the resistor 232 formed by printing is about 50 μm.

According to the configuration of the anode substrate 2 as shown in FIG. 7, even if a spark occurs between the anode substrate 2 and the cathode substrate 1, current from other than the striped metal back unit 231 corresponding to the spark portion is caused by the resistor 232. It can be suppressed. And since the electric charge accumulate | stored in each striped metal back unit 231 mainly flows through the spark current, the spark current does not increase. Therefore, destruction of the electron source can be prevented.
FIG. 8 is an enlarged plan view showing the arrangement in the planar direction of the phosphor, the BM 22, and the stripe-shaped metal back unit 231 in the display region of FIG. In FIG. 8, red (R), green (G), and blue (B) phosphors 21 are arranged in the horizontal direction. Each phosphor constitutes a sub-pixel, and a pixel is formed by three phosphors of R, G, and B. The horizontal pitch of each sub-pixel is 0.173 mm, and the horizontal pitch of the pixels is 0,519 mm. The phosphors of the same color are arranged in the longitudinal direction of the screen, and the pitch of the phosphors in the longitudinal direction is 0.519 mm. Therefore, the pixel unit is a square.

  Each horizontal arrangement (row) of phosphors is covered with a striped metal back unit 231. Therefore, each stripe-shaped metal back unit 231 has a long stripe shape in the horizontal direction. The stripes are insulated from each other except for the resistor portions formed on both sides of the screen. The vertical dimension of the phosphor is about 0.2 mm, and the stripe-shaped metal back unit 231 needs to completely cover the phosphor. Therefore, the width of the stripe-shaped metal back unit 231 needs to be about 0.3 mm. . Then, the distance between the stripe-shaped metal back unit 231 and the stripe-shaped metal back unit 231 can be secured at about 0.219 mm.

  FIG. 9 is a cross-sectional view taken along the line AA of FIG. In FIG. 9, the phosphors are arranged at a vertical pitch of 0.519 mm. A BM 22 is formed between the phosphors. The BM 22 has a two-layer structure. Cr2O3 having a thickness of 20 nm is deposited on the anode substrate 2 side, and Cr having a thickness of 200 nm is laminated thereon. The reflection of the BM22 portion is effectively prevented by laminating substances having different refractive indexes.

  A stripe-shaped metal back unit 231 is attached so as to cover a part of the phosphor and the BM 22. The striped metal back unit 231 is formed by vapor deposition. As shown in FIG. 9, the striped metal back units 231 are separated from each other. However, although each stripe-shaped metal back unit 231 is separated, it is laminated on Cr. Since Cr is conductive, insulation between the stripe-shaped metal back units 231 cannot be achieved. Therefore, even if the metal back is divided into the stripe-shaped metal back units 231 in the BM 22 of the conventional example, a predetermined effect is improved. I can't do that.

10 is a cross-sectional view taken along line AA of FIG. 8 according to the configuration of the present invention. The difference from the conventional example of FIG. 9 is that BM22 is made of a glass material mainly composed of vanadium oxide. A glass material mainly composed of vanadium oxide has a very high resistivity of 10 ⁸ Ωcm or more. Therefore, when a spark occurs, a resistance sufficient to prevent the charge charged in the adjacent stripe-shaped metal back unit 231 from flowing in is formed. As a component of the glass material mainly composed of insulating vanadium oxide, for example, V ₂ O ₅ : 30% to 40%, ZnO: 5%, BaO: 15%, WO ₃ : 5%, TeO ₂ : 25% To 35% + balance. Among these, when the V ₂ O ₅ component increases, the conductivity tends to increase. On the other hand, the glass material containing vanadium oxide as a main component is black and has a sufficient light absorption rate to act as BM22.

  A glass material mainly composed of vanadium oxide can be formed on the anode substrate 2 by printing. According to printing, the BM 22 can be formed while forming holes for the phosphor. In addition to this, for example, a glass material containing vanadium oxide as a main component can be applied to the entire surface of the anode substrate 2 and sintered, and then subjected to sand blasting to form holes in the portion where the phosphor is to be formed.

Another material that can be used as BM22 in the present invention is diamond-like carbon. Diamond-like carbon has an intermediate molecular structure between graphite and diamond, and has a high specific resistance of 10 ¹⁰ Ωcm or more. It is black and has a very high light absorption rate. Diamond-like carbon can be deposited on the anode substrate 2 by a CVD method. Holes for phosphors are formed on the diamond-like carbon film deposited on the anode substrate 2 by photolithography.

  11 is a cross-sectional view taken along the line CC of FIG. In FIG. 11, R, G, and B phosphors are juxtaposed with BM 22 in between. BM22 is a glass material mainly composed of vanadium oxide or diamond-like carbon as in FIG. A stripe-shaped metal back unit 231 is attached to cover the phosphor and the BM 22. In FIG. 11, the striped metal back unit 231 is a continuous film.

  The above is the case where the stripe-shaped metal back unit 231 covers one phosphor line. The smaller the stripe width forming the stripe-shaped metal back unit 231, the smaller the current value when sparking can be made. However, the present invention can also be applied to the case where the stripe width of the stripe-shaped metal back unit 231 covers phosphors in a plurality of rows. FIG. 12 shows an embodiment in which the stripe-shaped metal back unit 231 covers two rows of phosphors. In this case, the interval between the stripe-shaped metal back units 231 is about 0.2 mm, which is the same as the case where the stripe-shaped metal back units 231 cover one row of phosphors.

  13 is a cross-sectional view taken along line AA in FIG. In FIG. 13, phosphors of the same color are arranged in parallel with the BM 22 in between. The BM 22 is made of a glass material mainly composed of vanadium oxide or diamond-like carbon. A stripe-shaped metal back unit 231 is formed so as to cover the phosphor and the BM 22. In this case, the stripe-shaped metal back unit 231 covers two phosphors, that is, two rows. The striped metal back units 231 are separated from each other on the BM 22.

Also in the present embodiment, the BM 22 having a resistivity of 10 ⁸ Ω or more is formed of a glass material or diamond-like carbon whose main component is vanadium oxide, so that electrical insulation between the striped metal back units 231 is maintained. The current when a spark occurs can be suppressed.

  As described above, the present invention can also be applied to the case where the stripe-shaped metal back unit 231 covers a plurality of rows of phosphors. However, if the stripe-shaped metal back unit 231 covers too many rows of phosphors, the effect of reducing the spark current, which is the object of the invention, is diminished. On the other hand, the width separating the stripe-shaped metal back units 231 is constant regardless of the number of rows of phosphors covered by the stripe-shaped metal back units 231. Therefore, it is preferable to keep the number of phosphor lines covered by the unit to about five lines.

  In order to implement the present invention, it is necessary to form a very fine Al pattern by mask vapor deposition or mask sputtering (hereinafter referred to as mask vapor deposition). This embodiment discloses a method for forming a metal back that enables the configuration disclosed in the first embodiment. FIG. 14 is a schematic diagram showing a state in which an Al pattern is formed by mask vapor deposition according to the present invention. That is, FIG. 14 shows a state of only the Al pattern before the resistor 232 is applied.

  In FIG. 14, a metal back peripheral portion 233 of Al is formed in a frame shape so as to surround the display area. A number of thin striped Al patterns are formed in the display area. A power feeding portion 235 for supplying a high voltage from the contact spring is formed in the upper right corner. Since the metal back peripheral portion 233 is formed in a frame shape, such an Al pattern cannot be formed with only one mask.

  FIG. 15 shows a first embodiment of the vapor deposition method. This embodiment is an example in which a metal back is formed by two vapor depositions or sputtering (hereinafter represented by vapor deposition). FIG. 15A shows the shape of the first mask MK. 231M shown in FIG. 15A is a slit-like hole corresponding to the stripe-shaped metal back unit 231 formed on the anode substrate 2, and 233M is a hole corresponding to the metal back peripheral portion 233 formed on the anode substrate 2. It is.

  A number of slits 231 </ b> M are formed in the maximum of FIG. 15A, and this pitch is twice that of the stripe-shaped metal back unit 231 formed on the anode substrate 2. In FIG. 15A, a hole 233M is formed so that a part of the metal back peripheral portion 233 of the anode substrate 2 is deposited. If 233M is formed all around, the mask MK cannot be manufactured. However, if the metal back peripheral portion 233 formed on the anode substrate 2 is not formed in an annular shape, the mask MK can be manufactured.

  FIG. 15B shows a second mask MK for forming a metal back. A large number of slits 231M corresponding to the stripe-shaped metal back unit 231 of the anode substrate 2 are also formed in the mask MK in FIG. This pitch is twice that of the striped metal back unit 231 formed on the anode substrate 2. However, the position of the slit-shaped hole 231M of the mask MK in FIG. 15B is formed at a position alternate with that in FIG. 15A, and the mask MK in FIG. 15A and the position in FIG. After vapor deposition using both masks MK, a stripe-shaped metal back unit 231 corresponding to the vertical pitch of the phosphor is formed.

  A part of the hole 233M for forming the metal back peripheral portion 233 of the anode substrate 2 is formed in the mask MK of FIG. The metal back peripheral part 233 of the anode substrate 2 is completed by the hole 233M of the mask MK in FIG. 15A and the hole 233M of the mask MK in FIG. 2331M formed on the mask MK in FIG. 15A and the mask MK in FIG. 15B is a portion where the deposited Al overlaps.

  The shape of the metal back of the anode substrate 2 formed in this way is shown in FIG. In FIG. 15C, the vertical pitch of the striped metal back unit 231 is ½ of the pitch of 233M of the mask MK shown in FIGS. 15A and 15B. The strength of the mask MK is increased as the slit pitch of the mask MK is larger, and the mask MK is easy to handle. A portion 2331 partially present in the metal back peripheral portion 233 in FIG. 15C is a portion where Al is double-deposited.

  FIG. 16 shows a second embodiment for forming a metal back embodying the present invention. In this embodiment, as shown in FIGS. 16A, 16B, and 16C, the first mask MK, the second mask MK, and the third mask MK are used for vapor deposition. In the first mask MK shown in FIG. 16A, a large number of stripe-shaped slits 231M for forming the stripe-shaped metal back unit 231 are formed. The pitch of the slits 231M is three times that of the stripe-shaped metal back unit 231 formed on the anode substrate 2. The greater the pitch, the greater the mask strength and the easier handling of the mask MK. Holes for forming part of the peripheral edge of the anode substrate 2 are formed in the lower right and lower left of the first mask MK shown in FIG.

  In the second mask MK shown in FIG. 16B, a large number of striped slits for forming the striped metal back unit 231 are formed. The pitch of the slits is three times the pitch of the striped metal back unit 231 formed on the anode substrate 2. However, the position of the slit is different from the position of the slit of the first mask MK. Further, the second mask MK is formed with four holes for forming the sides of the metal back peripheral portion 233 of the anode substrate 2 in the vertical and horizontal directions.

  In the third mask MK shown in FIG. 16C, a large number of stripe-shaped slits for forming the stripe-shaped metal back unit 231 are formed. The pitch of the slits is three times the pitch of the striped metal back unit 231 formed on the anode substrate 2. However, the position of the slit is different from the position of the slit of the first mask MK and the second mask MK. Holes for forming part of the peripheral edge of the anode substrate 2 are formed in the upper right and upper left of the third mask MK. When vapor deposition is performed using the first mask MK, the second mask MK, and the third mask MK, an annular metal back peripheral portion 233 is formed on the anode substrate 2.

  FIG. 16D shows a state in which Al is deposited using the first, second, and third masks. In FIG. 16D, the vertical pitch of the striped metal back unit 231 is the same as the vertical pitch of the phosphor, and is 1/3 of the slit pitch of the first, second, and third masks. The metal back peripheral portion 233 has an annular shape, and an Al overlap portion 2331 is formed in part of the metal back peripheral portion 233.

  Thus, in this embodiment, since vapor deposition is performed using three masks, the strength of each mask is strong, and accurate vapor deposition is possible accordingly.

  FIG. 17 shows a third embodiment for forming a metal back embodying the present invention. In this embodiment, as shown in FIGS. 17A, 17B, and 17C, vapor deposition is performed using the first mask MK, the second mask MK, and the third mask MK. . In the first mask MK shown in FIG. 17A, a large number of stripe-shaped slits 231M for forming the stripe-shaped metal back unit 231 are formed. The pitch of the slits 231M is three times that of the stripe-shaped metal back unit 231 formed on the anode substrate 2. The greater the pitch, the greater the mask strength and the easier handling of the mask MK. Holes for forming the short sides of the peripheral edge of the anode substrate 2 are formed on the right and left sides of the first mask MK shown in FIG.

  In the second mask MK shown in FIG. 17B, a large number of stripe-shaped slits for forming the stripe-shaped metal back unit 231 are formed. The pitch of the slits is three times the pitch of the striped metal back unit 231 formed on the anode substrate 2. However, the position of the slit is different from the position of the slit of the first mask MK. The second mask MK is formed with elongated holes for forming the upper side and the lower side of the metal back peripheral part 233 of the anode substrate 2 in the vertical direction.

  In the third mask MK shown in FIG. 17C, a large number of stripe-shaped slits for forming the stripe-shaped metal back unit 231 are formed. The pitch of the slits is three times the pitch of the striped metal back unit 231 formed on the anode substrate 2. However, the position of the slit is different from the position of the slit of the first mask MK and the second mask MK. The third mask MK is not formed with a hole for forming the peripheral edge portion of the anode substrate 2.

FIG. 17D shows a state in which Al is deposited using the first, second, and third masks. In FIG. 17D, the vertical pitch of the stripe-shaped metal back unit 231 is the same as the vertical pitch of the phosphor, and is 1/3 of the slit pitch of the first, second, and third masks. The metal back peripheral portion 233 has an annular shape, and an Al overlap portion 2331 is formed at a corner portion of the metal back peripheral portion 233. The feature of this embodiment is that the pattern is formed using three masks on the metal back effective surface where the mask strength is a problem.
As described above, since the vapor deposition is performed using the three masks also in the present embodiment, the strength of each mask is strong, and thus accurate vapor deposition is possible.

  After Al is formed on the anode substrate 2 as described above, a resistor 232 is formed by screen printing using a mask SMK as shown in FIG. 18, and a metal back as shown in FIG. 7 is completed. Graphite is used for the resistor 232. Graphite is fired after printing. The film thickness after firing is about 5 μm. The volume low efficiency of the graphite after firing is several Ωcm, but the resistance between the metal back peripheral portion 233 and the striped metal back unit 231 is several kilohms to several tens of kilohms. This is because the only part that contributes to conduction is the lower part of the graphite film.

  In the above description, the width of the stripe-shaped metal back unit 231 covers one line of the phosphor. When the width of the stripe-shaped metal back unit 231 covers two rows of phosphors, the width of the slit of each mask may be almost doubled. In this case, the pitch of the striped slits formed in the mask is also doubled.

It is a top view of FED of this invention. It is a side view of FIG. It is AA sectional drawing of FIG. It is CC sectional drawing of FIG. It is BB sectional drawing of FIG. It is an inner side top view of the anode substrate of a prior art example. It is an inner side top view of the anode substrate of this invention. It is an enlarged plan view of a phosphor portion of an anode substrate. It is AA sectional drawing of FIG. It is AA sectional drawing of FIG. 8 in this invention. It is BB sectional drawing of FIG. 8 in this invention. It is another example of the enlarged plan view of the fluorescent substance part of an anode substrate. It is AA sectional drawing of FIG. It is the shape of the metal back | bag of this invention. It is an example of the mask which forms the metal back | bag of this invention. It is another example of the mask which forms the metal back | bag of this invention. It is another example of the mask which forms the metal back | bag of this invention. It is an example of the mask for screen printing which forms a resistor.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Cathode substrate, 2 ... Anode substrate, 3 ... Sealing part, 4 ... Spacer, 5 ... Terminal, 6 ... Exhaust substrate, 8 ... Exhaust pipe, 10. .. Through hole, 11... Scanning line, 12... Data signal line, 13 .. insulating film, 14... Electron source, 21. ..Metal back, 24 ... Anode terminal, 31 ... Sealing frame, 32, 33, 41 ... Frit glass, 50 ... Contact spring, 231 ... Stripe metal back unit, 232 ..Resistors, 233... Metal back peripheral portion, 235... Power feeding portion, MK... Mask, SMK.

Claims (19)

A cathode substrate in which an electron source is formed in a matrix, and a display device including an anode substrate facing the cathode substrate and having an effective screen formed by forming a phosphor in a location corresponding to the electron source,
The phosphor has a horizontal pitch and a vertical pitch, a black matrix is formed between the phosphors, and a plurality of long horizontal screens are applied to the phosphor and the black matrix to which an anode voltage is applied. Striped metal backs are formed, and the plurality of striped metal backs are separated from each other on the black matrix,
A peripheral portion for supplying an anode voltage to the metal back is formed of the same material as the metal back around the stripe-shaped metal back, and the striped metal back and the peripheral portion are formed by resistors. Connected,
The display device, wherein the black matrix is made of a glass material mainly composed of vanadium oxide having a resistivity of 10 ⁸ Ωcm or more.   The display device according to claim 1, wherein a width of the stripe-shaped metal back is smaller than a vertical pitch of the phosphor.   The display device according to claim 1, wherein a width of the stripe-shaped metal back is smaller than five times a vertical pitch of the phosphor. The display device according to claim 1, wherein a resistivity of the glass material containing vanadium oxide as a main component is 10 ⁸ Ωcm or more.   The display device according to claim 1, wherein the black matrix is formed of a glass material containing 30% to 40% of vanadium oxide.   The display device according to claim 1, wherein the peripheral portion has a ring shape surrounding the effective screen.   The display device according to claim 1, wherein the resistors are formed on the left and right sides of the screen.   The display device according to claim 1, wherein the resistor is made of graphite. A cathode substrate in which an electron source is formed in a matrix, and a display device including an anode substrate facing the cathode substrate and having an effective screen formed by forming a phosphor in a location corresponding to the electron source,
The phosphor has a horizontal pitch and a vertical pitch, a black matrix is formed between the phosphors, and a plurality of long horizontal screens are applied to the phosphor and the black matrix to which an anode voltage is applied. Striped metal backs are formed, and the plurality of striped metal backs are separated from each other on the black matrix,
A peripheral portion for supplying an anode voltage to the metal back is formed of the same material as the metal back around the stripe-shaped metal back, and the striped metal back and the peripheral portion are formed by resistors. Connected,
The display device, wherein the black matrix is formed of diamond-like carbon having a resistivity of 10 ¹⁰ Ωcm or more.   The display device according to claim 9, wherein a width of the stripe-shaped metal back is smaller than a vertical pitch of the phosphors.   The display device according to claim 9, wherein a width of the stripe-shaped metal back is smaller than five times a vertical pitch of the phosphor. The display device according to claim 9, wherein the diamond-like carbon has a resistivity of 10 ¹⁰ Ωcm or more.   The display device according to claim 9, wherein the peripheral portion has a ring shape surrounding the effective screen.   The display device according to claim 9, wherein the resistors are formed on left and right sides of the screen.   The display device according to claim 9, wherein the resistor is made of graphite. A cathode substrate in which an electron source is formed in a matrix, and a display device including an anode substrate facing the cathode substrate and having an effective screen formed by forming a phosphor in a location corresponding to the electron source,
The phosphor has a horizontal pitch and a vertical pitch, a black matrix is formed between the phosphors, and a plurality of long horizontal screens are applied to the phosphor and the black matrix to which an anode voltage is applied. Striped metal backs are formed, and the plurality of striped metal backs are separated from each other on the black matrix,
Around the periphery of the striped metal back, a peripheral portion for supplying an anode voltage to the metal back is formed of the same material as the metal back,
The display device, wherein the plurality of striped metal backs are formed by a plurality of mask vapor depositions or mask sputterings using different masks. The plurality of stripe-shaped metal backs are formed by first mask deposition using a first mask, or mask sputtering, and second mask deposition using a second mask or mask sputtering. ,
The pitch of the slits for forming the stripe-shaped metal back formed on the first mask and the pitch of the slits for forming the stripe-shaped metal back formed on the second mask are as follows: The display device according to claim 16, wherein the display device is twice the pitch of the striped metal back. The plurality of stripe-shaped metal backs use a first mask, a first mask vapor deposition or mask sputtering, a second mask uses a second mask vapor deposition or mask sputtering, and a third mask. Formed by third mask vapor deposition or mask sputtering using
A pitch of slits for forming the stripe-shaped metal back formed in the first mask, and a pitch of slits for forming the stripe-shaped metal back formed in the second mask; The display according to claim 16, wherein the pitch of the slits for forming the stripe-shaped metal back formed on the third mask is three times the pitch of the stripe-shaped metal back. apparatus. The peripheral portion is formed to circulate around the plurality of stripe-shaped metal backs by a plurality of mask vapor depositions or mask sputtering,
The display device according to claim 16, wherein the films formed by the plurality of mask vapor deposition or mask sputtering overlap each other.

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