JP2006093054A - Image display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image display device having a front substrate superior in discharge characteristics compared with a conventional one. <P>SOLUTION: The image display device comprises a front substrate 11 having a fluorescent screen 15 including a phosphor layer 16 and a light shielding layer 17, stripe-shaped metal back layers 20 superposed on the fluorescent screen 15, and a getter-cut layer 21 arranged between the metal back layers 20; a rear substrate 12 which is arranged opposed to the front substrate 11, having an electron emission element 18 arranged for emitting electrons toward the fluorescent screen 15; and a plurality of spacers 14 located between the rear substrate 12 and the getter-cut layers 20. The end face of the spacer 14 located at the getter-cut layer side is formed into indented-shape and a material which is depressed or cut apart by pressure contact of the spacer is used as a material for the getter-cut layer 21. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an image display device, and more particularly to an image display device having a structure excellent in discharge resistance characteristics.

  In recent years, as a next-generation image display device, a flat-type image display device in which a large number of electron-emitting devices are arranged to face an image display surface has been developed. There are various types of electron-emitting devices, and all of them basically use electron emission by an electric field, and image display devices using these electron-emitting devices are generally field emission displays (hereinafter referred to as field emission displays). , Referred to as FED). Among such FEDs, an image display device using a surface conduction electron-emitting device is also called a surface conduction electron-emitting display (hereinafter referred to as SED), but the term FED is used as a general term including SED. Use.

In general, the FED has a front substrate and a rear substrate that are opposed to each other with a predetermined gap. These substrates are joined to each other at their peripheral parts via a rectangular frame-shaped side wall to constitute a vacuum envelope. The inside of the vacuum envelope is maintained at a high vacuum with a degree of vacuum of about 10 ⁻⁴ Pa or less. Further, in order to support an atmospheric pressure load applied to the back substrate and the front substrate, a plurality of support members are disposed between these substrates.

  On the inner surface of the front substrate, a phosphor screen including phosphor layers that respectively emit red, blue, and green is formed. In order to obtain practical display characteristics, an aluminum thin film called a metal back layer is formed in stripes on the phosphor screen. Furthermore, in order to adsorb the gas remaining inside the vacuum envelope and the gas released from each substrate (for example, hydrogen, methane, oxygen, carbon dioxide, water vapor, etc.), it has a gas adsorption characteristic called getter layer. A metal thin film such as Ba (barium), V (vanadium), Ti (titanium), and Ta (tantalum) is deposited on the metal back layer.

  A large number of electron-emitting devices that emit electrons for exciting the phosphor to emit light are provided on the inner surface of the rear substrate. A large number of scanning lines and signal lines are formed in a matrix and connected to each electron-emitting device. In addition, a large number of spacers formed in the shape of plates or columns are arranged between the back substrate and the front substrate in order to support atmospheric pressure acting on these substrates.

  In such an FED, an anode voltage is applied to the image display surface including the phosphor layer and the metal back layer, and the electron beam emitted from the electron-emitting device is accelerated by the anode voltage and collides with the phosphor screen. The phosphor emits light. Thereby, an image is displayed on the image display surface. In this case, the anode voltage is desired to be at least several kV, preferably 10 kV or more.

  In such an FED, the gap between the front substrate and the rear substrate can be set to about 1 to 2 mm, which is significantly larger than that of a cathode ray tube (CRT) used as a display of a current television or computer. Weight reduction and thickness reduction can be achieved.

For example, Patent Document 1 is known as a specific conventional image display device.
Japanese Patent Laid-Open No. 10-326583

  By the way, in the conventional image display apparatus, a method of dividing the metal back layer is employed in order to maintain the discharge resistance of the front substrate. As an example, as shown in FIG. 6, for example, a phosphor screen 4 including a phosphor layer 2 and a light shielding layer 3 is formed on a front substrate 1, a metal back layer 5 is formed, and then an adjacent metal back layer 5 is formed. A getter cut layer 6 is provided between them. However, when metal deposition is performed as shown by arrow X in FIG. 6 to form a getter layer on the metal back layer 5, the metal film 7 is also formed on the getter cut layer 6, so that the adjacent metal back layer There has been a problem that the five are electrically connected to each other.

  In the conventional image display device, as described above, the spacer is disposed between the back substrate and the front substrate. For example, as shown in FIG. 7, it has been considered that this spacer is disposed between a back substrate (not shown) and the getter cut layer 6 on the front substrate 1 from the viewpoint of layout. However, in this case, a part of the getter cut layer 6 falls off at a portion where the end face of the spacer 8 contacts the getter cut layer 6 to generate particles 9, which causes discharge. Therefore, there is a problem that the getter cut layer 6 cannot be disposed on the line where the spacer is to be formed.

  The present invention has been made in view of the above-described problems, and an object thereof is to provide an image display device that is superior in discharge characteristics on a front substrate as compared with the conventional one.

  An image display device according to a first aspect of the present invention is arranged between a phosphor screen including a phosphor layer and a light shielding layer, a striped metal back layer provided on the phosphor screen, and the metal back layer. A front substrate having a getter-cut layer; a rear substrate disposed opposite to the front substrate; and an electron-emitting device that emits electrons toward the phosphor screen; and the rear substrate; A plurality of spacers located between the getter cut layers, and an end surface located on the getter cut layer side of the spacers having an uneven shape, and a material that is recessed or divided by pressure contact of the spacers as a material of the getter cut layer It is characterized by using.

  According to the image display device of the present invention, the end surface located on the getter cut layer side of the spacer is made uneven, and the material that is recessed or divided by the pressure contact of the spacer is used as the material of the getter cut layer. The adjacent metal back layers can be electrically cut off completely or in a substantially cut off state, so that the discharge characteristics can be improved as compared with the conventional device.

  According to the present invention, it is possible to provide an image display device that is superior in discharge characteristics as compared with the prior art.

  An image display apparatus according to an embodiment of the present invention will be described below with reference to FIGS. Here, as an image display device according to the present invention, an FED including a surface conduction electron-emitting device will be described as an example.

First, an overall view of the FED will be described with reference to FIGS.
As shown in FIGS. 1 and 2, the FED includes a front substrate 11 and a rear substrate 12 that are opposed to each other with a gap of 1 to 2 mm. Each of the front substrate 11 and the rear substrate 12 is configured by using a rectangular glass plate having a thickness of about 1 to 3 mm as an insulating substrate. The front substrate 11 and the back substrate 12 are flat rectangular vacuum envelopes whose peripheral portions are bonded to each other via a rectangular frame-shaped side wall 13 and whose inside is maintained at a high vacuum of about 10 ⁻⁴ Pa. 10 is constituted.

  The vacuum envelope 10 includes a plurality of spacers 14 provided therein for supporting an atmospheric pressure load applied to the front substrate 11 and the rear substrate 12. Here, the spacer 14 has a plate shape, but a columnar shape or the like can also be used. Details of the spacer 14 will be described later.

  A fluorescent screen 15 is formed on the inner surface of the front substrate 11. The phosphor screen 15 includes a phosphor layer 16 that emits red, green, and blue light, respectively, and a light absorption layer (light shielding layer) 17 that is arranged in a matrix. A metal back layer 20 that functions as an anode electrode and a getter layer (not shown) are formed on the phosphor screen 15. The phosphor layer 16 is formed on, for example, dots. The metal back layer 20 is formed of an aluminum alloy film or the like. The getter layer is formed of a metal film (for example, a titanium film) having gas adsorption characteristics, and the gas remaining in the vacuum envelope 10 and the gas released from each substrate (for example, hydrogen, methane, oxygen, carbon dioxide) , Water vapor, etc.). A getter cutter layer 21 is formed on the phosphor screen 15 between the metal back layers 20.

  The back substrate 12 includes a surface conduction electron-emitting device 18 on its inner surface. The electron-emitting device 18 functions as an electron source that excites the phosphor layer 16 of the phosphor screen 15. That is, the plurality of electron-emitting devices 18 are arranged in a plurality of columns and a plurality of rows corresponding to each pixel on the back substrate 12, and each emits an electron beam toward the phosphor layer 16. Each electron-emitting device 18 includes an electron emitting portion (not shown) and a pair of device electrodes for applying a voltage to the electron emitting portion. In addition, a large number of wirings 22 for supplying a potential to the electron-emitting device 18 are provided on the inner surface of the rear substrate 12 in a matrix shape, and end portions thereof are drawn out of the vacuum envelope 10.

  In such an FED, an anode voltage is applied to an image display surface including the phosphor screen 15 and the metal back layer 20 during an image display operation. Then, the electron beam emitted from the electron emitter 18 is accelerated by the anode voltage and collides with the phosphor screen 15. As a result, the phosphor layer 16 on the phosphor screen 15 is excited and emits light in the corresponding colors. In this way, a color image is displayed on the image display surface.

Next, the arrangement configuration of the spacers 14 and the formation method thereof will be described in detail.
As shown in FIG. 3, a getter cut layer 21 is formed on the phosphor screen 15 between the adjacent metal back layers 20. The end surface of the spacer 14 in contact with the getter cut layer 21 is an uneven surface 14 a, and the getter cut layer 21 in contact with the uneven surface 14 a is an oxide 23.

  The spacer 14 is pressed against the getter cut layer 21 as shown in FIGS. That is, first, as shown in FIG. 4A, the spacer 14 with the oxidation promoter 24 applied to the front end surface (lower end surface) is positioned directly above the getter cut layer 21. Next, the spacer 21 is pressurized while heating the getter cut layer 21 with the oxidation accelerator 24 facing downward. Accordingly, the oxidation promoter 24 on the front end surface of the spacer 14 functions when the getter cut layer 21 is pressurized, and the getter cut layer 21 with which the front end surface of the spacer 14 contacts is partially oxidized to form the oxide 23. It becomes.

  In the present invention, as a means for making the end face of the spacer to have an uneven shape, for example, a blasting process is exemplified, but the invention is not limited thereto. Also, the shape of the end face is variously exemplified. For example, a regular uneven shape (the former) as shown in FIGS. 3 and 4 may be used, or an uneven shape (the latter) having a curved surface 14b as shown in FIG. Well, not particularly limited. Here, in both the former and the latter cases, the oxidation accelerator has an action of dividing the getter cut layer, and therefore it is preferable to apply the oxidation accelerator to the tip of the spacer.

  In the present invention, since the getter cut layer needs to be recessed or cut when pressed by a spacer, a material obtained by mixing a phosphor with a light shielding layer material such as manganese oxide or frit is particularly preferable.

Next, a specific structure of the FED configured as described above will be described in more detail with reference to FIG.
(First embodiment)
That is, in the FED according to the first embodiment, as shown in FIG. 3, a getter cut layer having a width of about 200 mm and a thickness of about 10 μm is provided on the lower surface side of the front substrate (glass substrate) 11 through a light shielding layer 17 made of a black pigment. 21 is formed. Here, the getter cut layer 21 is made of a material in which frit is mixed with manganese oxide. Between the getter-cut layer 21 and the back substrate 12, there is disposed a glass plate-like spacer 14 having a width of 200 μm whose upper end surface is formed into an uneven shape by blasting. Here, the spacer 14 is in pressure contact so that the upper end surface thereof bites into the getter cut layer 21, and the contact portion is an oxide 23.

  In the FED having such a configuration, the spacer 14 is pressed against the getter cut layer 21 as shown in FIGS. 4 (A) and 4 (B). That is, first, as shown in FIG. 4A, the spacer 14 with the oxidation promoter 24 applied to the front end surface (lower end surface) is positioned directly above the getter cut layer 21. Next, the spacer 21 is pressurized while heating the getter cut layer 21 with the oxidation accelerator 24 facing downward. Here, the heating heats the entire glass substrate on the abutting side, and the pressure to the spacer 14 at this time is atmospheric pressure. Accordingly, the oxidation promoter 24 on the front end surface of the spacer 14 functions when the getter cut layer 21 is pressurized, and the getter cut layer 21 with which the front end surface of the spacer 14 contacts is partially oxidized to form the oxide 23. It becomes.

  Thus, in the said 1st Embodiment, while making the end surface located in the getter cut layer side of the spacer 14 uneven | corrugated shape, the oxidation promoter 24 is apply | coated to the uneven surface side surface of the spacer 14, and also the said getter cut As the material of the layer 14, a material that is recessed by the pressure contact of the spacer 14, that is, (manganese oxide + frit + phosphor) is used. The getter cut layer 14 with which the accelerator 24 abuts is oxidized to become an oxide 23, and the adjacent metal back layers 20 can be electrically cut off. Accordingly, the discharge characteristics on the front substrate side can be improved as compared with the conventional apparatus.

  In the first embodiment, the above-described materials are used as the spacer, the getter cut layer, and the oxidation accelerator, but the present invention is not limited to this. Further, the width of the spacer and the thickness of the getter cut layer are not limited to those described above. Further, the shape of the end face of the spacer is not an uneven shape by blasting as shown in FIG. 3 or FIG. 4, but is an uneven shape having a curved surface 14b as shown in FIG. 5, and the getter cut layer is easily cut. Such a shape may be used.

  Further, the present invention is not limited to the above-described embodiments as they are, and can be embodied by modifying the constituent elements without departing from the spirit of the invention in the stage of implementation. Further, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, you may combine suitably the component covering different embodiment.

FIG. 1 is a perspective view schematically showing an example of an FED manufactured by a manufacturing method and a manufacturing apparatus according to an embodiment of the present invention. FIG. 2 is a diagram schematically showing a cross-sectional structure along the line AA of the FED shown in FIG. FIG. 3 is an enlarged view of a main part of FIG. FIG. 4 is a cross-sectional view showing a method of forming spacers in the FED shown in FIG. FIG. 5 is an explanatory diagram of another spacer different from the spacer used in the FED shown in FIG. FIG. 6 is an explanatory diagram for explaining a problem in forming a getter layer on the front substrate side in a conventional FED. FIG. 7 is an explanatory diagram for explaining a problem in forming a spacer on a getter cutter layer on the front substrate side in a conventional FED.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Vacuum envelope, 11 ... Front substrate, 12 ... Back substrate, 15 ... Phosphor screen, 16 ... Phosphor layer, 17 ... Light absorption layer (light-shielding layer), 18 ... Electron emission element, 20 ... Metal back layer, 21 ... Getter cut layer, 22 ... Wiring, 23 ... Oxide, 24 ... Oxidation promoter.

Claims (3)

A front substrate having a phosphor screen including a phosphor layer and a light shielding layer, a striped metal back layer provided on the phosphor screen, and a getter cut layer disposed between the metal back layers;
A rear substrate disposed opposite to the front substrate and disposed with an electron-emitting device that emits electrons toward the phosphor screen;
A plurality of spacers positioned between the back substrate and the getter cut layer,
An image display device characterized in that an end face located on the getter cut layer side of the spacer has an uneven shape, and a material that is recessed or divided by pressure contact of the spacer is used as the material of the getter cut layer. The spacer has a function of partially oxidizing the getter cutter layer by pre-applying an oxidation accelerator to an end face on the side in pressure contact with the getter cut layer and pressurizing and heating the getter cutter layer. 1. The image display device according to 1. The image display device according to claim 1, wherein an end surface of the spacer is formed into an uneven shape by blasting.

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