JP3119406B2 - Electronic 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 an electronic display device for a computer terminal or a television receiver.

[0002]

2. Description of the Related Art FIGS. 3 to 6 show a schematic structure of a flat display device in a conventional electronic display device. FIG. 3 is a side sectional view showing the whole device, and FIG. FIG. 5 is an enlarged perspective view showing details of a main part, and FIG. 6 is an enlarged sectional view showing a matrix structure. In this flat display device, a fluorescent screen 5 in which a phosphor is applied to the inner surface of a front glass 4a of a flat glass sealed container 4 is formed. on the other hand,
An electron emission source 3 is constituted by the linear hot cathode 1 and the perforated cover electrode 2, and the thermoelectrons generated from the plurality of linear hot cathodes 1 are
It is drawn out by the perforated cover electrode 2 and directed to the matrix structure 6 for controlling electrons. Matrix structure 6
A second grid electrode 11 for more efficiently drawing electrons to the matrix structure 6 is provided between the second grid electrode 11 and the electron radiation source 3.

The direction of emission of electrons emitted from the linear hot cathode 1 of the electron emission source 3 is adjusted by the perforated cover electrode 2. The potential of the matrix structure 6 and the distance between the electron emission source 3 and the matrix structure 6 are adjusted so that the electrons that have exited the electron emission source 3 project toward the matrix structure 6 as vertically as possible, like a shower. In order to extract the electron beam more efficiently, the second grid electrode 11 is provided. The matrix structure 6 is provided on the side of the electron radiation source 3 on the insulating substrate 8.
A first control electrode group 9 is provided with a metal electrode 9a;
In opposition to this, a second control electrode group 10 including a metal electrode 10a is provided on the fluorescent screen 5 side. A large number of small round holes are formed in the insulating substrate 8 of the matrix structure 6 to form electron passing holes 7. As shown in FIG. 5, in the matrix structure 6, the metal electrodes 9a and 10a are provided for each row of the electron passage holes 7, and are insulated by the separator 12 for each row. Also,
As shown in FIG. 5, the direction of the second control electrode group 10 formed in the direction of one row of the electron passage holes 7 is orthogonal to the direction of the first control electrode group 9.

[0004] That is, a specific electron passage is performed by applying a potential applied to the first control electrode group 9 and the second control electrode group 10 to the electrons extracted so that the electron beam collides perpendicularly with the matrix structure 6. Turn on the electron beam for each hole 7
Can be -OFF. The electron beam that has exited the matrix structure 6 is accelerated and converged by applying, for example, 15 KV to an electrode provided on the back surface of the fluorescent screen 5 by aluminum evaporation. At this time, as shown in FIG. 6, a converging electrode 13 may be provided close to the matrix structure 6 so as to converge more finely on the fluorescent screen 5.

FIG. 8 illustrates the structure of a shadow mask type color picture tube (hereinafter referred to as CRT) which has been conventionally used. A CRT 21 has a fluorescent screen 23 on its inner surface.
, A funnel 24 extending from the panel 22, and a neck 25 containing an electron gun (not shown). The fluorescent screen 23 is composed of small round dot-shaped or stripe-shaped red, green, and blue light-emitting mosaic dots. Fluorescent screen 2
Opposite to 3, a shadow mask 26 in which a small round hole or a slit-like or slot-like hole is formed in a thin metal plate to form an electron passage hole 27 is arranged. The three electron beams operate the shadow mask 26 as a color selection electrode to project a color image.

FIG. 9 is a view for explaining the functions of the shadow mask 26 and the fluorescent screen 23 of the conventional shadow mask type CRT. The focused and accelerated electron beam 29 from the electron gun collides with, for example, a shadow mask 26 formed of a thin metal plate 28 having a thickness t of about 0.15 mm of an SPCC material. Each of the red, green, and blue dots R provided on the inner surface of the panel 22 at a certain angle is limited to the electron beam of a determined size.
It hits the fluorescent screen 23 composed of mosaic dots of D, GD, and BD, and emits light.

[0007]

[Problems to be solved by the invention]

By the way , in the case of the shadow mask type CRT shown in FIG. 8, as shown in FIG.
The beam diameter φ2 of the electron beam 29 impinging on the electron passing hole 27 is usually φ2 ≒ (1.1 to 1..
4) When the size of the fluorescent dot is φ3 and the size of the fluorescent dot is φ3, half of the difference between the beam diameters φ2 and φ3 on the screen is the guard band Δ, and this Δ is the color purity margin. If the size is too small, manufacturing variations cannot be absorbed and color misregistration will occur. For this reason, in the case of a shadow mask type color CRT, it has been a conventional technical problem how to make a small hole neatly over the entire screen with respect to the plate thickness t of the shadow mask 26. = 0.7t is the limit, and there is a problem that the working accuracy cannot be improved any more.

[0009] This invention has been made in view of the points mentioned above, in the electrostatic Kode Isupurei apparatus shea catcher <br/> Doumasuku formula, easily electrically controlled can be the amount and size of the electron beam with a simple structure To enable the use of thicker shadow masks
None, together with electronic screens at the center and periphery of the phosphor screen
Change the size of the
Improved electronic data to increase the guard band Δ.
It proposes a display device .

[0010]

Electronic display device according to this invention, there is provided a means to provide a process, an electron emission source including a cathode for supplying an electron beam, a number of the passing over Symbol electron beam is disposed in front of the electron emission source Shadow with electron passage hole
A mask, and a phosphor screen the electron beams passing through the shadow mask facing to disposed above Symbol electron passing hole is irradiated, the shadow mask is formed of a semiconductor substrate, the said electron emission source side and The above fluorescent screen
The first and second electrodes are formed on the
Is, on the side wall surface of each electron passage hole of the first and second
Exposed portion above the semiconductor substrate is exposed to the portion sandwiched between the electrode
It has a variable a conductive position to be applied to the first and second electrodes
An electronic beam that scans the center of the fluorescent screen.
Beam size smaller than the electron beam that scans the surrounding area.
That's what I did .

[0011]

[0012]

[Action]

[0013] <br/> in electronic display device according to the invention this is first in the side wall surface of the electron passing holes of the shadow mask
A and the exposed portion of the resistivity of the semiconductor substrate sandwiched between the second electrode, the balance between that conductive position be applied to the first and second electrodes, aperture size of the electron beam passing through the electron passage over hole , it is possible to reduce the apparent pore, this reason Shadouma
The thickness of the disk can be increased, and the first and second electrodes can be marked.
By making the applied potential variable, the fluorescent screen
The size of the electron beam can be changed between the center and the periphery.
Can Ru.

[0014]

【Example】

Example 1 _- Figure 1 is a flat display device matrix structure 16
Is an embodiment of the present invention applied to a matrix structure 1
The semiconductor substrate 18 constituting the material 6 is made of a material such as Synox A (trade name) which is an alumina-based composite material (Al ₂ O ₃ + TiN) of Asahi Glass Co., Ltd. or Synox S (trade name) which is a SiC (SiC + Al ₂ O ₃ ). Is used. On this semiconductor substrate 18, an electrode 10a is formed on the upper surface facing the fluorescent screen, and an electrode 9a is formed on the lower surface facing the electron emission source. And the electron passing holes 1 of the matrix structure 16
An exposed portion 18a where the semiconductor substrate 18 is directly exposed is provided between the electrodes 10a and 9a at the central portion of the side wall of 7.

The electrodes 10a and 9a are strip-shaped electrodes corresponding to, for example, a fluorescent screen, and 10a and 9a are orthogonal to each other. Therefore, a point corresponding to one point on the fluorescent screen can be specified by the electrodes 10a and 9a. The electrodes 10a and 9a are provided directly on the semiconductor substrate 18 with a material such as aluminum. The resistivity of general aluminum is about 2 × 10 ⁻⁶ Ω · cm, and the above-mentioned Synox A used as the semiconductor substrate 18 is 10 ⁸ to 1
It is about ^{9 5} Ω · cm and about 10 ⁵ to 10 ⁷ Ω · cm for Synox S.

In this embodiment, when +60 V and +35 V are applied as control voltages to the electrodes 10 a and 9 a, respectively, the exposed portion 18 a of the semiconductor substrate 18 is provided on the side wall of the electron passing hole 17 of the matrix structure 16. 17
The zero equipotential line in the vicinity does not block the electron passage hole 17 as shown by the broken line in FIG. 1, and the degree of blocking the passage of negatively charged electrons through the electron passage hole 17 is as shown in FIG. It is much smaller than the equipotential line shape of 0 potential in the case. Therefore, the transmittance of the electron beam passing through the matrix structure 16 is determined by the size of the electron passage hole 17 itself, and the luminance can be improved.

In this embodiment, the electrodes 10a, 9
The control voltage applied to a is, for example, +60 V and +35 V. However, in order to function as an electrode, the substrate 18 of the matrix structure 16 also needs to have withstand voltage characteristics, and the value of the control voltage is only an example, and is higher. Considering driving by voltage, the lower limit of the resistivity of the semiconductor substrate 18 is about 10 ³ Ω · cm.

Embodiment 2 FIG. FIG. 2 shows an embodiment applied to a shadow mask of a shadow mask type CRT. Normally, a material such as SPCC is used for the shadow mask 36, but here, a semiconductor substrate 38 is used as in the matrix structure of FIG. 1, and electrodes 40a and 39a are provided on one surface and the other surface. This electrode may be a strip-shaped orthogonal electrode as shown in FIG. 1, or may be an electrode connected over the entire surface of the electrode 40a and the other surface of the electrode 39a. Also in this embodiment, the electrodes 40a,
An exposed portion 38a where the semiconductor substrate 38 is directly exposed between the holes 39a is provided, and an equipotential line of zero potential is intentionally projected as shown by a broken line in FIG. 2 to substantially narrow the electron beam passing through the electron passage hole 37. Perform For example, the semiconductor substrate 38 is made closer to glass by increasing the amount of the alumina component than in the case of the first embodiment. The resistivity in this case is 10 ¹¹ Ω
・ Cm and smaller than glass.

In the second embodiment, the size of the electron beam passing through the electron passage hole 37 due to the projection of the equipotential line of 0 potential becomes φ2, while the size of the physical small hole φ1 as the shadow mask 36 becomes φ2. Can be substantially reduced. That is, the shadow mask 36 can be formed with a hole φ1 larger than a required electron beam diameter. Therefore, since the shadow mask 36 can be formed with the larger hole φ1 with the same thickness t of the mask, a high quality mask can be easily formed. Conversely, the size of the electron beam of the same φ2 can be constituted by a thicker shadow mask, and the shadow mask 26 having high rigidity and small thermal deformation, that is, small doming can be constituted.

The potentials applied to the electrode 40a and the electrode 39a may be, for example, the same and constant. Further, the potential applied to the electrodes 40a and 39a may be varied between the center and the periphery of the fluorescent screen so that the electron beam is narrowed when scanning the central part of the fluorescent screen rather than when scanning the peripheral part. . In this case, it is usually desired to increase the difference between the electron beam diameter and the phosphor dot diameter, that is, the guard band Δ, in the peripheral portion of the fluorescent screen. Therefore, in the peripheral portion, the protruding amount of the zero potential equipotential line may be reduced. .

[0021]

【The invention's effect】

[0022] <br/> in electronic display device according to the invention this is to be able to narrow the apparent electron passing holes of the shadow mask, it is possible to use a thicker shadow mask, the rigidity of the shadow mask In addition, the thermal deformation of the mask can be reduced, and a highly accurate display can be obtained. Also applied to the first and second electrodes
The potential at the center of the shadow mask
By narrowing the beam diameter from the periphery, shadow mask
To make guard band Δ larger at the periphery than at the center
Can be easily realized, and the occurrence of color shift can be effectively prevented.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a matrix structure in a flat display device according to a first embodiment of the present invention.

FIG. 2 is a shadow mask type CRT according to a second embodiment of the present invention.
FIG. 2 is a schematic diagram showing a shadow mask structure in FIG.

FIG. 3 is a side sectional view showing the entire conventional flat display device.

FIG. 4 is an enlarged layout view showing a positional relationship between components in a conventional flat display device.

FIG. 5 is an enlarged perspective view showing details of a main part in a conventional flat display device.

FIG. 6 is an enlarged sectional view showing a matrix structure in a conventional flat display device.

FIG. 7 is an enlarged sectional view of a main part of a matrix structure in a conventional flat display device.

FIG. 8 is a schematic structural view showing a conventional shadow mask type color picture tube.

FIG. 9 is an enlarged sectional view of a main part showing a shadow mask of a conventional shadow mask type color picture tube.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Linear hot cathode 2 ... Perforated cover electrode 3 ... Electron radiation source 4 ... Glass sealed container 4a ... Front glass 5 ... Fluorescent screen 6 ... Matrix structure 7 ...・ Electron passing hole 8 ・ ・ ・ Insulating substrate 9 ・ ・ ・ First control electrode group 9a ・ ・ Metal electrode 10 ・ ・ Second control electrode group 10a ・ Metal electrode 11 ・ ・ Second grid electrode 12 ・ ・ Separator 13. Focusing electrode 21 CRT 22 Panel 23 Fluorescent screen 24 Funnel 25 Neck 26 Shadow mask 27 Electron passing hole 28 Metal substrate 29 Electron beam 36・ Shadow mask 37 ・ ・ Electron passage hole 38 ・ ・ Semiconductor substrate 38a ・ Exposed part 39a ・ Electrode 40a ・ Electrode

Continuation of the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H01J 29/07 H01J 31/12

Claims (2)

(57) [Claims] 1. A Shadouma having an electron emitting source including a cathode for supplying an electron beam, a number of electron passing holes on Symbol electron beam is disposed in front of the electron emission source passes
Disk and, and a phosphor screen the electron beam passing through the arranged opposite to the shadow mask on Symbol electron passing hole is irradiated, the shadow mask is formed of a semiconductor substrate, the said electron emission source side and The above fluorescent screen
First and second electrodes are respectively formed on the side surface ,
The first and second electrodes are provided on the side wall surface of each of the electron passage holes.
It has an exposed portion where the semiconductor substrate sandwiched by portions is exposed in a variable electric position to be applied to the first and second electrodes
And an electron beam that scans the center of the fluorescent screen.
The beam size smaller than the electron beam scanning its periphery
Electronic display device, characterized in that the the like. 2. A semiconductor substrate constituting a shadow mask.
But the resistivity 10 ¹¹ to 10 ³ [Omega] cm electronic display device of claim 1, wherein <br/> that a ceramic material.