JP3158923B2 - Display device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a phosphor for displaying an image or the like and a display envelope for accommodating an electron source for exciting the phosphor. The present invention relates to a display device having an insulating support inside so that is maintained at a predetermined interval, and is particularly suitable for a display device having a field emission cathode.

[0002]

2. Description of the Related Art An electric field applied to a metal or semiconductor surface is 10
^At about ⁹ [V / m], electrons pass through the barrier and emit electrons in a vacuum even at room temperature due to the tunnel effect.
This phenomenon has been known for a long time as field emission (Field Emission), and a cathode that emits electrons by using such a principle is called a field emission cathode (Fiel Emission).
d Emission Cathode). In recent years, it has become possible to make the above-described micron-sized field emission cathode by making full use of semiconductor microfabrication technology. By forming a large number of field emission cathodes on a substrate, it is possible to create a surface emission type field emission array. It is possible. It has been proposed to apply such a field emission array as an electron source for a display device, a CRT, an electron microscope, or an electron beam device.

FIG. 9 shows a conventional display device as an example of an application example. In this display device, a glass cathode substrate 115 on which a field emission array is formed and a transparent glass substrate on which a phosphor is formed are shown. Are arranged facing each other at a predetermined interval, thereby forming an envelope for maintaining the inside at a high vacuum. The field emission array formed on the cathode substrate 115 has a stripe-shaped cathode line electrode 11 formed by sputtering or the like.
1, a resistor layer 114 formed thereon, a plurality of emitter cone groups 112 formed thereon, and a gate line electrode 110 formed near the tip of the emitter cone group 112. (Spindt)
Field emission array. Note that the resistance layer 114
An insulating layer 113 is stacked thereon, and a gate line electrode 110 is formed on the insulating layer 113.

The pitch between the emitter cones of the emitter cone group 112 can be formed with a dimension of 10 μm or less.
It is arranged to provide 100,000 pieces on one cathode substrate 115. In this field emission array, since the distance between the gate and the cathode can be made submicron, a voltage V of only several tens of volts is applied between the gate and the cathode.
Electrons can be emitted from the emitter cone group 112 by applying _GE .

[0005] An anode electrode 101 is formed on an anode substrate 104, and a phosphor dot pattern 102 is formed on the anode electrode 101. Therefore, when a positive voltage _VA is applied to the anode electrode 101, electrons emitted from the emitter cone group 112 are captured by the anode electrode 101. At this time, the captured electrons are captured by the anode electrode 101. The phosphor dot pattern 102 illuminates because it collides with and excites the phosphor dot pattern 102 laminated thereon. This emission can be observed through the transparent anode substrate 104.

Further, in this display device, the inside of an envelope formed by the cathode substrate 115 and the anode substrate 104 is made to have a high vacuum, so that the cathode substrate 115 and the anode substrate 104 are separated from each other by the influence of atmospheric pressure. Since the gap may not be maintained, the insulating pillar 103 is provided between the cathode substrate 115 and the anode substrate 104. The insulating pillar 103 is formed of an insulator such as glass, and has a cathode substrate 115 and an anode substrate 104.
Are provided at predetermined intervals.

The upper end of the insulating column 103 is disposed so as to contact the anode electrode 101 formed on the anode substrate 104, and the lower end of the insulating column 103 is formed on the insulating layer 113 of the cathode substrate 115. The gate line electrode 111 is disposed so as to contact the gate line electrode 111.

A matrix is formed by a plurality of striped cathode line electrodes 111 formed on the cathode substrate 115 and a striped gate line electrode 110 formed so as to be orthogonal to the cathode line electrodes 111. The matrix is scanned by a cathode scanning unit and a gate scanning unit (not shown). This allows
Electrons are selectively emitted from the emitter cone group 11 according to an image signal.
2 and the corresponding phosphor dot pattern 10
2 emits light, and an image is displayed on the anode substrate 104. In this case, for example, an image signal is applied to the gate scanning unit, and one image is displayed on the anode substrate 104 when scanning of one field is completed.

[0009]

However, in the conventional display device, since the insulating pillar is directly in contact with the gate line electrode, when the insulating pillar is pressurized by the atmospheric pressure, the gate line electrode is turned off. There is a problem in that the gate line electrode and the cathode line electrode may be short-circuited due to the deformation, and the insulating layer provided below the gate line electrode may be broken. In addition, since one end of the insulating support is directly in contact with the anode electrode and the other end is directly in contact with the gate line electrode, surface charging easily occurs when the insulating support is charged, and the anode electrode and the gate line electrode are easily charged. There is a problem that it is not possible to electrically isolate the above.

Therefore, according to the present invention, even if the insulating pillar is provided, the gate line electrode and the cathode line electrode are not short-circuited and the anode electrode and the gate line electrode are electrically isolated. It is an object of the present invention to provide a display device capable of performing such a display.

[0011]

In order to achieve the above object, a display device according to the present invention comprises a transparent anode substrate provided with an anode electrode having a phosphor, and emits electrons for exciting the phosphor. And a plurality of cathode substrates provided with at least a gate electrode and a cathode electrode for the transparent anode substrate and the cathode substrate so that the transparent anode substrate and the cathode substrate face each other at a predetermined distance. And a notch provided at an edge portion of the anode electrode in the vicinity of a contact position of the provided insulating post, and the cathode substrate has a notch. ,
A notch is provided at an edge portion of the gate electrode and the cathode electrode in the vicinity of a contact position of the insulating pillar provided.

In the display device, the anode electrode may be formed of a transparent electrode formed on a stripe, and a phosphor layer on a dot pattern for forming a pixel may be formed thereon. Further, a striped cathode electrode is formed on the cathode substrate, and then a resistive layer and an insulating layer are formed thereon, and the striped gate electrode is formed on the insulating layer by the cathode. It is formed so as to be orthogonal to the electrode, and is arranged so that one end of the insulating pillar is in contact with the insulating layer.

[0013]

According to the present invention, since the insulating pillar is provided so as to correspond to the notch provided at the edge of the anode electrode, the cathode line electrode and the gate line electrode, the insulating pillar is formed below the gate line electrode. Even if the insulating layer is deformed, short circuit between the gate line electrode and the cathode line electrode is prevented. Further, since the insulating pillar is not disposed in contact with the anode electrode and the gate line electrode, the anode electrode and the gate line electrode can be electrically isolated even if the insulating pillar is charged.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows the structure of an anode substrate and FIG. 2 shows the structure of a cathode substrate in one embodiment of the display device of the present invention.
FIG. 3 is a side sectional view. The display device of this embodiment is a field emission display device (FE) using a field emission cathode as an electron source.
D). In these figures, 1 is a plurality of stripe-shaped anode electrodes A1 to A9 formed on the inner surface of the anode substrate 5, 2 is a phosphor dot pattern formed as dot-shaped pixels on the anode electrode 1,
Reference numeral 3 denotes an insulating support provided between the anode substrate 5 and the cathode substrate 16 at a predetermined interval so as to maintain the anode substrate 5 and the cathode substrate 16 at a predetermined interval. Reference numeral 4 denotes a notch formed at an edge of the anode electrode 1, and reference numeral 5 denotes an anode substrate made of transparent glass. is there.

Reference numeral 10 denotes a plurality of stripe-shaped gate line electrodes G1 to G7 formed on the insulating layer 13, and reference numeral 11 denotes a stripe-shaped K1 to K5 formed on the inner surface of the cathode substrate 16. A plurality of cathode line electrodes 12, a conical emitter cone group formed on the resistance layer 14 so as to correspond to the phosphor dot pattern 2;
Reference numeral 13 denotes an insulating layer formed on the resistance layer 14 excluding a portion where the emitter cone group 12 is formed, and 14 denotes a cathode voltage applied to the cathode line electrode 11 to the emitter cone group 12. The resistance layer 15 is a cutout formed at the edge of the cathode line electrode 11 and the gate line electrode 10, and 16 is a cathode substrate made of glass.

In the display device configured as described above,
Glass cathode substrate 1 on which field emission array is formed
6 and an anode substrate 5 made of transparent glass are arranged to face each other at a predetermined interval to form an envelope which holds the inside at a high vacuum. The field emission array formed on the cathode substrate 16 includes a striped cathode line electrode 11 formed by sputtering or the like, a resistance layer 14 formed thereon, and a plurality of emitter cone groups formed thereon. 12 and a gate line electrode 10 formed near the tip of the emitter cone group 12 to form a Spindt-type field emission array. Note that an insulating layer 13 is stacked on the resistance layer 14, and the gate line electrode 10 is formed on the insulating layer 13.

FIG. 2 shows an insulating layer 13 and a resistance layer 14.
Is omitted and the cathode substrate 16 is
FIG. 3 is a diagram showing an arrangement of a cathode line electrode 11 and a gate line electrode 10 as seen through the substrate. As shown in this figure, an emitter cone group 12 is formed in a large number of square cutout regions formed in the cathode line electrode 11, and the pitch between the emitter cones of the emitter cone group 12 is 10 μm or less. It has been created in. A large number of such emitter cones are provided in a rectangular cutout region formed in the cathode line electrode 11, and tens of thousands to hundreds of thousands are provided on one cathode substrate 15.

In this field emission array, the distance between the gate and the cathode can be made submicron, and the gate line electrode 10 is formed so as to overlap the rectangular cutout area formed in the cathode line electrode 11.
Because it is provided with rectangular cutout region also it can emit electrons from the emitter cone group 12 by applying a voltage V _GE of only a few 10 volts between the gate line electrode 10 and the cathode line electrodes 11. Incidentally, the anode electrode 1 formed on the anode substrate 5 as described above is used.
When the phosphor dot pattern 2 is laminated thereon and a positive voltage _VA is applied to the anode electrode 1, the electrons emitted from the emitter cone group 12 at the corresponding position are:
It becomes trapped by the anode electrode 1 and at this time,
The trapped electrons collide with the phosphor dot pattern 2 laminated on the anode electrode 1 to excite it,
The phosphor dot pattern 2 emits light. This light emission can be observed through the transparent anode substrate 5.

Further, since the inside of the envelope is made to have a high vacuum, the envelope is pressed inward by the atmospheric pressure,
Since the cathode substrate 15 and the anode substrate 104 may not be able to maintain a predetermined interval, the insulating support 3 is disposed between the cathode substrate 15 and the anode substrate 5 as shown in FIG. Like that. The insulating posts 3 are formed of an insulator such as glass fiber, and a plurality of the insulating posts 3 are provided at predetermined intervals, for example, approximately every 2 mm between the cathode substrate 15 and the anode substrate 5. And
The upper end of the insulating pillar 3 is directly in contact with the anode substrate 104. In this case, the insulating support 3
So that the anode electrode 1 does not contact the anode electrode 1.
₁ , a notch 4 having a depth d ₁ and a length d ₂ is formed at the edge of the insulating column 3 as shown in FIG. It is disposed so as to be located substantially at the center of the notch 4 of A4.

As a result, even if the position of the insulating column 3 is slightly shifted, the insulating column 3 is prevented from contacting the anode electrode 1. As shown in FIG. 3, the lower end of the insulating support 3 is connected to the insulating layer 13 of the cathode substrate 16.
It is arranged to abut against. In this case, the insulating support 3
Is formed at the edge of the gate line electrode 10 as shown in FIG.
The insulating pillar 3 is disposed so as to be located substantially at the center of the cutout 15 of the adjacent gate line electrodes G6 and G7 as shown in a partially enlarged view in FIG.

Further, the notch 1 of the gate line electrode 10
2 is also shown at the edge of the cathode line electrode 11 corresponding to FIG.
A notch 17 is provided as shown in FIG. Therefore, the notch 15 formed at the edge of the gate line electrode 10 and the notch 17 formed at the edge of the cathode line electrode 11 form a substantially square notch as shown in a partially enlarged view of FIG. Become so. Thereby, even when the insulating support 3 is pressurized by the atmospheric pressure when the envelope is evacuated and the insulating layer 13 is deformed, the gate line electrode 10 and the cathode line electrode 11 do not exist immediately below the insulating support 3. , There is no contact between the two electrodes 10 and 11,
A short circuit accident between the gate line electrode 10 and the cathode line electrode 11 can be prevented.

Further, the insulating support column 3 is connected to the emitter cone group 12.
Even if charged by electrons emitted from the
Is not in contact with the anode electrode 1 and the gate line electrode 10, so that the electrical isolation between the electrodes 1 and 10 does not deteriorate. Therefore, even if the anode voltage applied to the anode electrode 1 is significantly increased, no leak occurs between the anode electrode 1 and the gate line electrode 10, so that the brightness of the display screen can be remarkably improved.

FIG. 2 shows a plurality of striped cathode line electrodes 11 formed on the cathode substrate 15 and a striped gate line electrode 10 formed so as to be orthogonal to the cathode line conductors 11. The matrix is configured as described above, and the matrix is scanned by a cathode scanning unit and a gate scanning unit (not shown). Thereby, electrons are sequentially emitted from the emitter cone group 12 in accordance with the image signal, and the corresponding phosphor dot pattern 2 emits light, so that an image is displayed on the anode substrate 5. In this case, for example, an image signal is applied to the gate scanning unit, and one image is displayed on the anode substrate 5 when scanning of one field is completed.

Also, the striped anode electrodes 1 shown in FIG. 1 to FIG.
0 is seven G1 to G7 cathode electrodes 11 are K1 to K5
However, this is for the sake of simplicity, and each striped electrode actually has a much larger number of electrodes. By the way, the cutouts formed at the edges of the striped anode electrode 1, gate line electrode 10, and cathode line electrode 11 are as follows:
The cutout is not limited to the rectangular notch as shown in FIGS. 1 and 2, but may be a semicircle as shown in FIG. 4A, a triangular shape as shown in FIG. 4B, or a triangular shape as shown in FIG. The trapezoidal shape shown in the figure or the inverted trapezoidal shape shown in FIG.

Next, FIG. 5 shows a modification of the structure on the anode substrate side in the display device according to one embodiment of the present invention.
(A) is a front view of the anode substrate, and (b) is a side sectional view of the anode substrate. Anode substrate 2 shown in this figure
Numeral 0 is made of soda glass, and an alkali ion passivation film 24 is formed on the surface thereof. The passivation film 24 is formed of, for example, a thin film of SiO ₂ .

On the passivation film 24, TiO
_{2 A} thin film 25 is formed, and a patterned anode electrode 21 is further formed thereon. In this case, Ti in contact with the patterned anode electrode 21
The O ₂ thin film 25 is heat-treated so as to form a colored layer 25-1. Further, a phosphor layer 22 is formed so as to cover the patterned anode electrode 21. As shown in FIG. 2A, the patterning of the anode electrode 21 is performed by etching and removing a square portion, and a large number of such square portions are provided on the anode electrode 21 vertically and horizontally. . And
The phosphor layer 22 is excited and emits light by the electrons applied to the square portion. That is, an image is displayed with the square portion being a pixel.

In this case, since the TiO ₂ thin film 25 is transparent, the displayed image can be observed through the anode substrate 20. In general, the pattern of the anode 21 having a high reflectance formed of aluminum is a colored layer. 25-1 so that the anode electrode 2
1 is prevented from being reflected on the display surface, and the contrast of the image is improved. In addition, a plurality of insulating posts 23 are provided so as to avoid pixels, and the portion of the anode electrode 21 on which the insulating posts 23 are provided is also patterned.

Next, FIG. 6 shows a process for fabricating the structure on the anode substrate side shown in FIG. First, as shown in FIG. 6A, an alkali ion passivation film 24 is formed on an anode substrate 20 made of soda glass, and an organic titanium compound 26 is further applied thereon and dried. Then
Firing at a temperature of 500 to 600 ° C for about 10 minutes, the same figure (B)
As shown in organotitanium compound film 26 of TiO ₂ thin film 2
Change to 5. Further, as shown in FIG.
An aluminum thin film 27 is deposited on the O ₂ thin film 25 by a sputtering method, a vapor deposition method, or the like. In this case, the aluminum thin film 25 is applied so as to have a thickness of about 1.1 μm.

Then, a photoresist is applied to the surface of the aluminum thin film 25, and the photoresist is patterned into a pattern by performing exposure and development treatments. Then, unnecessary portions of the aluminum thin film 25 are dissolved by etching. Then, an anode electrode 21 is formed as shown in FIG. Next, as shown in FIG. 3E, the anode electrode 2 is removed except for the portion where the insulating support 23 is provided.
The phosphor layer 22 is patterned in a planar shape on 1. When the insulating pillar is provided and the firing step is performed at a temperature of 450 to 550 ° C., the TiO ₂ thin film 25 in contact with the aluminum anode electrode 21 is colored, and the colored layer 25-1 is formed. Is done.

The reason that the TiO ₂ thin film 25 in contact with the anode electrode 21 is colored by the heat treatment is that the anode electrode 21 made of aluminum is oxidized by the TiO ₂ thin film 25 into aluminum oxide during the heat treatment.
It is presumed that the TiO ₂ thin film 25 is reduced and colored. It should be noted that non-alkali glass may be used instead of soda glass on which the passivation film 24 of SiO ₂ is formed.

As shown in FIG. 7 instead of the structure on the anode substrate side shown in FIG. 5, the function of the passivation film 24 and the coloring layer 25-1 is also used by the TiO ₂ thin film 25. The passivation film 24 of SiO ₂ formed on the anode substrate 20 may be omitted.
In this case, the thickness of the TiO ₂ thin film 25 is 500 to 150.
Preferably, it is 0 Å. The anode substrate 20 is made of soda glass. Further, FIG.
As shown in (2), in the electrode pattern of the anode electrode 21, the cross-shaped electrode 30 may be further provided in the square pattern to more reliably apply the anode voltage to the phosphor layer 22. .

In the above description, the case where the present invention is applied to a field emission type display device has been described. However, the present invention is not limited to this, and a display device in which an insulating column is provided in an envelope. For example, it can be applied to a fluorescent display tube or the like.

[0033]

As described above, according to the present invention, since the insulating pillar is provided in the notch provided at the edge of the anode electrode, the cathode line electrode and the gate line electrode, the insulating pillar is formed under the gate line electrode. Even if the formed insulating layer is deformed, it is possible to prevent a short circuit between the gate line electrode and the cathode line electrode. Further, since the insulating pillar is not disposed in contact with the anode electrode and the gate line electrode, the anode electrode and the gate line electrode can be electrically isolated even if the insulating pillar is charged. Therefore, the anode voltage applied to the anode electrode can be increased, and the brightness of the displayed image can be significantly improved.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration on an anode substrate side of an embodiment of a display device of the present invention.

FIG. 2 is a diagram showing a configuration on the cathode substrate side of an embodiment of the display device of the present invention.

FIG. 3 is a side sectional view of one embodiment of the display device of the present invention.

FIG. 4 is a modified example of a notch provided at an edge of a striped electrode.

FIG. 5 is a view showing a modification of the configuration on the anode substrate side of one embodiment of the display device of the present invention.

FIG. 6 is a view showing a manufacturing process of the modification shown in FIG. 5;

FIG. 7 is a diagram showing another modification of the configuration on the anode substrate side of one embodiment of the display device of the present invention.

FIG. 8 is a diagram showing still another modification of the configuration on the anode substrate side of one embodiment of the display device of the present invention.

FIG. 9 is a side sectional view of a conventional display device.

[Explanation of symbols]

1, 21 Anode electrode 2 Phosphor dot pattern 3, 23 Insulating support 4, 15, 17, 41 Notch 5, 20 Anode substrate 10 Gate line electrode 11 Cathode line electrode 12 Emitter cone group 13 Insulating layer 14 Resistance layer 16 Cathode substrate Reference Signs List 22 phosphor layer 24 passivation layer 25 TiO ₂ layer 25-1 coloring layer 26 organotitanium compound 27 aluminum thin film 30 cross electrode 40 stripe electrode

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Katsutoshi Muko 629 Oshiba, Mobara-shi, Chiba Futaba Electronics Industry Co., Ltd. (72) Inventor Tatsuo Yamaura 629 Oshiba, Mobara-shi, Chiba Futaba Electronics Industry Co., Ltd. 56) References JP-A-6-119876 (JP, A) JP-A-5-114373 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01J 31/12 H01J 29/87

Claims (1)

(57) [Claims] 1. A dot-like fluorescent and transparent anode substrate stripe <br/> anode electrode is provided with a stripe for emitting electrons exciting the phosphor
Through the insulating layer Jo gate electrode and the stripe-shaped cathode electrode
A plurality of cathode substrates are provided between the transparent anode substrate and the cathode substrate so that the transparent anode substrate and the cathode substrate face each other at a predetermined interval. One of the insulating props
A notch is provided at an edge portion of the striped anode electrode near an abutting position of the provided insulating pillar on the transparent anode substrate, and an end is provided so as to contact the insulating layer. And in the cathode substrate, the stripe-shaped gate electrode near the contact position of the insulating pillar provided and the
A display device, wherein a notch is provided at an edge portion of a striped cathode electrode.