JPS62150640A - Flat matrix type cathode-ray tube - Google Patents

Abstract

PURPOSE:To prevent the unnecessary discharge along the surface of a spacer glass, and to supplement the function as an acceleration electrode and unify the diffusion of electron beams so as to improve the luminous level, by coating an electroconductive layer of carbon or the like at the upper portion at a face glass side of the spacer glass facing to the bottom plate glass side. CONSTITUTION:At the upper portion of a spacer glass 3 at a face glass side, an electroconductive layer 4 of carbon or the like is coated facing to a bottom plate glass 2 side. The electroconductive layer 4 is coated up to about the middle portion between the face glass 1 and the bottom plate glass 2. Therefore, a specific resistance is given by the coating of the conductive layer 4 to prevent the unnecessary discharge along the surface of the spacer glass 3 and to maintain a specific potential, so that the function of screening plates 1b as acceleration electrodes is supplemented and the diffusion property of electron beams can be exercised. Therefore, the diffusion of the electron beams is made even and the decrease of the luminous level at the periphery of the face glass 1 can be prevented.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a flat matrix CRT used as a lighting element of a large image display device.
In particular, the aim is to improve the level of light emitted at the periphery of the display surface.

[Conventional technology]

Figure 2 shows a flat matrix CRT that has already been proposed.
(1) is a cross-sectional view showing the configuration of the main parts of the anode electrode (1a), which is formed by coating the inside with a phosphor.
(2) is a filament (2a), and the electron beam emitted from this filament is accelerated toward the anode electrode (1a). X electrode (2b)
The bottom plate glass (8) is integrally formed by being fused to the face glass (1) and the bottom plate glass (2) so as to cover the phosphor. This is a spacer glass that forms a box-shaped glass container that narrows toward the bottom glass (2).

In the flat matrix CRT configured as above,
The X electrode (2b) and the X electrode (2C) form a scanning electrode and a pixel electrode, and have a 4 x 47) IJ structure, and the phosphor coated on the corresponding anode electrode (1a) has a predetermined shape. A phosphor for red, green, or blue is coated at the position of 16 pixels in one element.
Colored green and blue 0 However, in order to arbitrarily select these pixels, it is sufficient to apply a voltage to each scanning electrode and pixel electrode, and only the part where voltage is applied to both electrodes is selected. It is made to emit light. As is well known, the electrons emitted from the filament are accelerated by the voltage applied to the scanning electrode and the grid electrode of the pixel electrode, and collide with the anode to which a high voltage is applied, causing the electrons to strike the anode electrode surface, for example. The coated phosphor emits light due to the collision energy at this time.

[Problem that the invention seeks to solve]

However, as mentioned above, in the flat matrix CRT, the peripheral part of the spacer glass (8) is
If the length of b) is increased, the distance between the grid electrodes will be shortened, causing a phenomenon of discharge along the glass surface. Conversely, if the distance between the electrodes is shortened, the distance between the grid electrodes will be shortened, causing discharge to occur along the top side of the spacer glass (8). The present invention has been developed as described above because it is easily charged and its function as an accelerating electrode is weakened, which weakens the diffusion of the electron beam. This was done to solve the problem, and it provides a flat matrix CRTf that can improve the light emission level around the outermost part of the face glass without causing a discharge phenomenon along the surface of the spacer glass. be.

[Means for solving problems]

The flat matrix CRT according to the present invention has a conductive layer of carbon or the like coated on the upper part of the spacer glass on the face glass side toward the bottom glass side.

[Effect]

According to the flat matrix CRT of the present invention, by applying a conductive layer such as carbon to the spacer glass, a predetermined resistance value can be imparted to prevent discharge along the surface of the spacer glass, and a predetermined potential can be applied to the spacer glass. It is possible to perform the function of diffusing the electron beam while maintaining the electron beam, thereby preventing a decrease in the light emission level around the face glass.

〔Example〕

Hereinafter, one embodiment of the present invention will be described with reference to FIG. 1, in which the same parts as in FIG. 2 are denoted by the same reference numerals.

The difference between Fig. 1 and Fig. 2 is that a conductive layer (4) of carbon or the like is applied to the stop on the 7 ace glass (1) side of the spacer glass (8) toward the bottom glass (2). In other respects, they are the same. Note that the conductive layer (4) is applied to approximately the middle position between the face glass (1) and the bottom glass (2).

Therefore, according to the above embodiment, a predetermined resistance value is imparted to the spacer glass (8) by coating the conductive layer (4).
It is possible to prevent unnecessary discharge along the creeping surface of the electron beam and to maintain a predetermined potential, which complements the function of the baffle plate (1b) as an accelerating electrode and performs the function of diffusing the electron beam, resulting in uniform diffusion. Therefore, it is possible to prevent a decrease in the light emission level in the periphery of the face glass (1).

〔Effect of the invention〕

As described above, according to the present invention, by applying a conductive layer such as carbon to the upper part of the face glass side of the spacer glass toward the bottom glass side, unnecessary discharge along the surface of the spacer glass can be prevented and accelerated. It can supplement the function of an electrode and uniformly diffuse the electron beam, thereby improving the light emission level.

[Brief explanation of drawings]

FIG. 1 is a schematic sectional view showing an embodiment of the present invention, and FIG. 2 is a schematic sectional view showing a basic technology of the present invention. In the figure, (1) is the face glass, (1a) is the anode electrode, (1b) is the front plate, (2) is the bottom plate glass, (2)
a) is a filament, (2b) is a U x 1M pole (grid), (2C) is a Y electrode (grid), (8) is a spacer glass, and (4) is a conductive layer. In addition, in the figures, the same symbols indicate the same or corresponding parts.

Claims (1)

[Claims] A face glass equipped with a plurality of anode electrodes each coated with a fluorescent material on the inside, a shielding plate for shielding between the anode electrodes, a filament, and an electron beam emitted from the filament is accelerated towards the anode electrode. a spacer that is integrally formed with the face glass and the bottom glass so as to cover the phosphor and forms a box-shaped glass container that narrows toward the bottom glass; A flat matrix CRT characterized in that a conductive layer of carbon or the like is coated on the upper part of the spacer glass on the face glass side toward the bottom glass side.