JP2006093055A - Image display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve brightness of a phosphor screen by increasing the quantity of an electron beam by arranging members composed of an electron multiplying material at least in an electron channel. <P>SOLUTION: The image display device is composed of a front substrate 2 having a phosphor screen 6 containing a plurality of phosphor layers and light-shielding layers and a metal back layer set overlapped on the phosphor screen; a rear-face substrate 3 arranged in opposition to the front substrate, having a plurality of electron emission elements 10a corresponding to the plurality of phosphor layers; a plate-like grid 14 arranged between the front-face substrate and the back-face substrate, having a number of beam-passing holes with a positional relation arrayed against the electron emission elements; and a plurality of pillar-like spacers arranged between the front substrate and the grid as well as between the rear-face substrate and the grid, for maintaining gaps between both the substrates and the grid. Members 17 made of electron multiplying materials are formed at least in a channel in which electrons from the electron emission elements 10 reach the phosphor layers. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention has a flat envelope having a flat panel structure, and emits electrons from an electron-emitting device provided on a back substrate to display a color image by exciting and emitting a phosphor layer provided on the front substrate. The present invention relates to an image display device.

  In recent years, field emission displays (FEDs), plasma displays (PDPs), and the like are known as display devices having a vacuum envelope with a flat flat panel structure. In addition, as a kind of FED, a display device (hereinafter referred to as SED) including a surface conduction electron-emitting device has been developed.

  The SED has a front substrate and a rear substrate that are opposed to each other with a predetermined gap. These substrates are joined to each other at peripheral edges via rectangular frame-shaped side walls, and the inside is evacuated to form a flat envelope having a flat panel structure.

  A phosphor layer of three colors is formed on the inner surface of the front substrate, and on the inner surface of the rear substrate, a large number of electron-emitting devices corresponding to each pixel are arranged as an electron emission source for exciting and emitting the phosphor layer. ing. A large number of wires for driving the electron-emitting devices are provided in a matrix on the inner surface of the rear substrate, and the end portions are drawn out of the vacuum envelope.

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

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

As a specific conventional image display device, for example, as in Patent Document 1, when a vacuum envelope of the device is configured, a plate-like shape having a plurality of spacers for maintaining a gap between two plates is used. A structure having a grid is known.
Japanese Patent Laid-Open No. 2003-197098

  By the way, in the conventional image display device, electrons emitted from the electron-emitting devices pass through the beam passage holes formed in the plate-like grid and are irradiated to the phosphor layer, but the electron emission efficiency is several percent. There was a problem that it was low and sufficient luminance could not be obtained on the phosphor screen.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to dispose an electron from an electron-emitting device by arranging a member made of an electron multiplying material in a passage through which electrons from the electron-emitting device pass. An object of the present invention is to provide an image display apparatus which can increase the brightness of the phosphor screen by increasing the amount of light.

  An image display device according to a first aspect of the present invention includes a front substrate having a phosphor screen including a plurality of phosphor layers and a light-shielding layer, a metal back layer provided on the phosphor screen, and the front substrate. A rear substrate having a plurality of electron-emitting devices corresponding to the plurality of phosphor layers arranged opposite to each other, and a position arranged between the front substrate and the rear substrate and aligned with the electron-emitting devices A plate-like grid in which a large number of beam passage holes are formed, and a plurality of columnar shapes arranged between the front substrate and the grid and between the back substrate and the grid to maintain a gap between the two substrates and the grid. An image display device comprising a spacer, wherein a member made of an electron multiplying material is formed at least in a passage until electrons from the electron-emitting device reach a phosphor layer.

  According to the image display device of the present invention, the amount of electrons from the electron-emitting device is conventionally increased by forming at least a member made of an electron multiplying material in a passage until electrons from the electron-emitting device reach the phosphor layer. As a result, the brightness of the phosphor screen can be increased.

  According to the present invention, it is possible to provide an image display apparatus capable of increasing the amount of electrons from the electron-emitting device and thereby improving the luminance of the phosphor screen.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. First, an SED will be described as an example of a display device according to an embodiment of the present invention.

  As shown in FIGS. 1 to 3, the SED 1 includes a front substrate 2 and a rear substrate 3 each made of a rectangular glass plate, and these substrates are opposed to each other with a gap of about 1.0 to 2.0 mm. Has been. The front substrate 2 and the rear substrate 3 are joined to each other through a rectangular frame-shaped side wall 4 made of glass, and constitute a vacuum envelope 5 having a flat flat panel structure with a vacuum inside. .

  A phosphor 6 that functions as an image display surface is formed on the inner surface of the front substrate 2. The phosphor 6 is configured by arranging red, blue, and green phosphor layers (R, G, B) 7 and a light shielding layer 8, and the phosphor layer 7 is formed in a stripe shape or a dot shape. A metal back layer 9 made of aluminum or the like is formed on the phosphor 6. Furthermore, it is called a getter layer (not shown) for adsorbing the gas remaining inside the vacuum envelope and the gas released from the writing substrate (eg hydrogen, methane, oxygen, carbon dioxide, water vapor, etc.) A metal thin film such as Ba (barium), V (vanadium), Ti (titanium), Ta (tantalum) having gas adsorption characteristics is deposited on the metal back layer.

  On the inner surface of the rear substrate 3, a number of surface conduction electron-emitting devices 10 each emitting an electron beam are provided as electron emission sources that emit electrons for exciting and emitting the phosphor layer 7 of the phosphor 6. ing. These electron-emitting devices 10 are arranged in a plurality of columns and a plurality of rows corresponding to each pixel. Each electron-emitting device 10 includes an electron emitting portion (not shown) and a pair of device electrodes for applying a voltage to the electron emitting portion. Further, on the inner surface of the back substrate 3, a large number of wirings 11 for applying a driving voltage to the respective electron-emitting devices 10 are provided in a matrix shape, and end portions thereof are drawn out of the vacuum envelope 5. Yes.

  The side wall 4 functioning as a bonding member is sealed to the peripheral edge of the front substrate 2 and the peripheral edge of the back substrate 3 by, for example, a sealing material 12 such as low melting glass or low melting metal, and these substrates are bonded to each other. is doing.

  As shown in FIGS. 2 to 4, the SED 1 includes a spacer structure 13 disposed between the front substrate 2 and the rear substrate 3. Here, the spacer structure 13 is composed of a grid 14 made of a rectangular metal plate and a large number of columnar spacers 15 (15a, 15b) which are integrally provided on both sides of the grid.

  The grid 14 has a first surface 14 a that faces the inner surface of the front substrate 2 and a second surface 14 b that faces the inner surface of the back substrate 3, and is arranged in parallel with these substrates. A large number of electron beam passage holes 16 are formed in the grid 14 by etching or the like. The electron beam passage holes 16 are arranged to face the electron emission elements 10 and allow the electron beams emitted from the electron emission elements 10 to pass therethrough.

In the present embodiment, a member 17 made of an electron multiplying material is embedded in the electron beam passage hole 16. Examples of the member 17 include BaTiO ₃ , TiO ₂ —ZnO, MgO, NaCl, BaO, Al ₂ O ₃ , SiO ₂ , Cu, Fe, Pt, Si, and Ge. This member is not limited to the case of embedding as shown in FIGS. 2 and 3, but may be formed on one side of the grid or on the front substrate side in the form of a film or a sheet as will be described later.

  On the first surface 14 a of the grid 14, a first spacer 15 a is integrally provided so as to be positioned between adjacent electron beam passage holes 16. The extending end of the first spacer 15 a is in contact with the inner surface of the front substrate 2 via the metal back 9 and the light shielding layer 11 of the phosphor 6. Further, on the second surface 14 b of the grid 14, a second spacer 15 b is integrally provided so as to be positioned between the adjacent electron beam passage holes 16. The extending end of the second spacer 15 b is in contact with the wiring 11 provided on the inner surface of the back substrate 3.

  The spacer structure 13 configured as described above is disposed between the front substrate 2 and the back substrate 3, and the first and second spacers 15a and 15b are brought into contact with the inner surfaces of the front substrate 2 and the back substrate 3, respectively. Thus, the atmospheric pressure load acting on these substrates is supported, and the interval between the substrates is maintained at a predetermined value.

  The SED 1 includes a voltage supply unit (not shown) that applies a voltage to the grid 14 and the metal back layer 9 of the front substrate 2. For example, a voltage of 12 kV is applied to the grid 14 and a voltage of 10 kV is applied to the metal back layer 9. Further, by applying a voltage to the grid 14, the member 17 made of an electron multiplying material can be provided with a function of multiplying electrons by an already known principle (for example, JP-A-5-182632).

  In the SED 1, when displaying an image, a voltage is applied between the element electrodes of the electron-emitting device 10 via the wiring 18 to emit an electron beam from an electron-emitting portion of the arbitrary electron-emitting device 10, and a phosphor. An anode voltage is applied to 6 and the metal back layer 9. The electron beam emitted from the electron emission portion is accelerated by the anode voltage, passes through the member 17 embedded in the electron beam passage hole 16 of the grid 14, and then collides with the phosphor 6. As a result, the amount of electrons is further increased after passing through the member 17, the phosphor layer 7 of the phosphor 6 is excited and emits light, and an image with higher brightness than the conventional one is displayed.

  When the SED 1 having the above structure is manufactured, the front substrate 2 on which the phosphor 6 and the metal back layer 9 are provided in advance, and the rear substrate 3 on which the electron-emitting device 10 and the wiring 18 are provided and the side wall 4 is bonded. And prepare. In addition, a spacer structure 13 in which a large number of spacers 15 a and 15 b are provided on the grid 14 is prepared.

  Then, the spacer structure 13 is positioned on the back substrate 3. In this state, the front substrate 2, the rear substrate 3, and the spacer structure 13 are arranged in a vacuum chamber (not shown), the inside of the vacuum chamber is evacuated, and then the front substrate 2 is joined to the rear substrate 3 through the side wall 4. . Thereby, SED1 provided with the spacer structure 13 is manufactured.

In the present invention, the arrangement of the member made of the electron multiplying material is not limited to the case of being embedded in the beam passage hole as shown in FIG. 2 and FIG.
1) As shown in FIG. 5, a member made of an electron multiplier material is formed in a sheet shape on one side (upper surface) of a plate-like grid, and the four corners of the member are gridded with a caulking tool (not shown). 14 configuration.

2) As shown in FIG. 6, a metal back layer and a getter layer are sequentially stacked inside the inner substrate via a phosphor screen, and a member made of an electron multiplier material is formed in a sheet shape between the metal back layer and the getter layer. Constitution.
3) As shown in FIG. 7, a configuration in which a plurality of sheet-like members made of an electron multiplying material are formed so as to be closed for each beam passage hole.
4) Usually, since the getter layer is formed of a plurality of layers, for example, as shown in FIG. 8, one of these layers is a plurality of sheet-like members made of an electron multiplier material. As described above, the sheet-like member is used as a component of the getter layer, and has an electromagnetic shielding effect and has an advantage that the adhesion of the getter layer can be improved.

Next, specific embodiments of the present invention will be described with reference to the drawings.
Example 1
Please refer to FIG. As shown in FIGS. 2 and 3, the SED according to the first embodiment opens a large number of beam passage holes 16 in a plate-like grid 14 in a positional relationship aligned with a large number of electron-emitting devices 10. A member 17 made of an electron multiplier material (BaTiO ₃ ) is embedded in each beam passage hole 16. Here, the member 17 is formed by being embedded in the beam passage hole 16 in a paste state and then dried.

  The SED according to the first embodiment has a configuration in which a member 17 made of an electron multiplying material is embedded in a number of beam passage holes 16 opened in a plate-like grid 14 that supports the upper and lower spacers 15a and 15b. Therefore, after the electrons emitted from the electron-emitting devices arranged on the inner surface of the back substrate 3 pass through the member 17 of the beam passage hole 16, the amount of electrons can be increased compared to the conventional case, and the luminance by the phosphor 6 is increased. Can be raised.

(Example 2)
Please refer to FIG. In the SED according to the second embodiment, as shown in FIG. 5, a sheet-like member 27 made of an electron multiplying material (BaTiO ₃ ) is formed on one surface (upper surface) of the plate-like grid 14. It is characterized in that one corner is caulked to the grid 14 by a caulking tool (not shown). The other components excluding the sheet-like member are as described in the description of FIGS.
According to the SED according to the second embodiment, the same effect as the first embodiment can be obtained, and the luminance can be improved by a simple process. In Example 2, the sheet-like member 27 can be fixed to the grid by spot welding without using a caulking tool.

(Example 3)
Please refer to FIG. In the SED according to the third embodiment, as shown in FIG. 6, a getter layer 28 made of Ti is formed on the metal back layer 9, and a sheet-like member 27 made of BaTiO ₃ is formed between the metal back layer 9 and the getter layer 28. It is the structure which formed. The other components excluding the sheet-like member 27 are as described in the description of FIGS.
According to the SED according to the third embodiment, the same effect as the first embodiment can be obtained.

Example 4
In the SED according to the fourth embodiment, as schematically shown in FIG. 8, the getter layer 28 is composed of two layers of a Ba layer 28a and a Ti layer 28b, and a sheet-like member 27 made of BaTiO _{3 is} composed of a Ba layer 28a. It is characterized by being formed between the sheet-like members 27. The other components excluding the getter layer and the sheet-like member are as described in the description of FIGS.
According to the SED according to the third embodiment, the same effects as those of the first embodiment can be obtained and the adhesion of the getter layer can be improved. The arrangement of the sheet-like members is not limited to that shown in FIG.

  Note that the above-described invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the 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 SED according to an embodiment of the present invention. FIG. 2 is a diagram schematically showing a cross-sectional structure taken along line II-II of the SED shown in FIG. FIG. 3 is a partially enlarged cross-sectional view showing the cross section of FIG. 2 partially enlarged. FIG. 4 is an external perspective view showing a spacer structure incorporated in the SED of FIG. FIG. 5 is a cross-sectional view schematically showing an SED according to another embodiment of the present invention. FIG. 6 is a cross-sectional view schematically showing an SED according to another embodiment of the present invention. FIG. 7 is a cross-sectional view schematically showing an SED according to still another embodiment of the present invention. FIG. 8 is a cross-sectional view schematically showing an SED according to still another embodiment of the present invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... SED, 2 ... Front substrate, 3 ... Surface substrate, 4 ... Side wall, 5 ... Vacuum envelope, 6 ... Phosphor, 7 ... Phosphor layer, 8 ... Light absorption layer (light shielding layer), 9 ... Metal back Layer, 11, 18 ... wiring, 12 ... sealing material, 13 ... spacer structure, 14 ... grid, 15, 15a, 15b ... spacer, 16 ... electron beam passage hole, 17, 27 ... member made of electron multiplying material, 28: Getter layer.

Claims (6)

A front substrate having a phosphor screen including a plurality of phosphor layers and a light shielding layer, and a metal back layer provided on the phosphor screen;
A rear substrate having a plurality of electron-emitting devices corresponding to the plurality of phosphor layers, disposed opposite to the front substrate;
A plate-like grid disposed between the front substrate and the rear substrate and having a plurality of beam passage holes formed in a positional relationship aligned with the electron-emitting devices;
An image display device comprising a plurality of columnar spacers arranged between the front substrate and the grid, between the rear substrate and the grid and maintaining a gap between the two substrates and the grid,
An image display device characterized in that a member made of an electron multiplying material is formed at least in a passage until electrons from the electron-emitting device reach the phosphor layer. The image display apparatus according to claim 1, wherein the member made of an electron multiplying material is embedded in the beam passage hole. The image display device according to claim 1, wherein the member made of an electron multiplying material is in the form of a sheet and is disposed on one side of the grid. 2. The image display device according to claim 1, wherein a getter layer is further formed on the metal back layer, and the member made of an electron multiplying material is formed in a sheet shape between the metal back layer and the getter layer. 5. The image display device according to claim 4, wherein the getter layer is formed by laminating a plurality of layers, and a member made of an electron multiplying material is formed in a sheet shape in any of the plurality of layers. 4. The image display device according to claim 3, wherein the sheet-like member made of an electron multiplying material is fixed to the grid by spot welding to the grid or by caulking at a plurality of locations.

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