RU2298854C1 - Field-effect cathode-luminescent matrix screen - Google Patents

Abstract

FIELD: cathodic-luminescence based low-voltage data display means; screens for digital and alphanumeric displays and universal panels for visualizing any desired information.

SUBSTANCE: novelty is that proposed field-effect cathode-luminescent matrix screen incorporating vacuum envelope assembled of flat transparent-glass face plate and flat anode board carrying anode electrodes covered with conducting layer and phosphor of at least one color, electron emitter matrix, external leads for connecting anode electrodes and electron emitters to voltage supply, insulating frame interconnecting face plate and anode board has its matrix of surface-conducting electron emitters formed on face plate; electron emitters are disposed against anode electrode over its perimeter to form light-emitting pixel location for emitting light excited by phosphor electrons on anode electrode through central surface of face plate free from electron emitters. As an alternative, matrix of surface-conducting electron emitters is formed on face plate and electron emitters are disposed against anode electrode to form light-emitting pixel location in central part of pixel coaxially with anode electrode for emitting light excited by phosphor electrons across anode electrode through face plate surface free from electron emitters over perimeter, black dielectric mask being disposed on transparent face plate between light-emitting pixel locations and dielectric mask, on anode board.

EFFECT: facilitated manufacture and enlarged functional capabilities of proposed screen.

2 cl, 4 dwg

Description

The invention relates to low-voltage means of displaying information based on cathodoluminescence and can be used in the development of devices for creating screens of digital and alphanumeric indicators, universal panels for visualizing the display of any information - text, character, graphic, reading devices of analog and discrete-analog measuring devices used in calculators, watches, indicator boards for collective use, etc.

In our country and abroad, especially in Japan, low-voltage cathodoluminescent indicators are widely used in electronic devices for domestic and industrial use, as well as in special equipment (see Gorfinkel B.I., Abalduev B.V., Medvedev R.S., Loginov A.P. Low-voltage cathodoluminescent indicators. - M.: Radio and communications, 1983).

A low-voltage cathodoluminescent indicator is a vacuum electronic device containing a thermionic cathode, control grids and holders enclosed in a vacuum shell with a board on which, according to a given pattern, conductive screen segments coated with a phosphor and conductive wiring with contact pads are placed.

In experimental samples, field-emission cathodes are a matrix commutated from a variety of micropoints located on a plane with a density of the order of 10,000 mm ² and providing the necessary level of field emission. An idea of the principle of action of the tip cathodes and the design of the matrix of cathodes is given in Fig. 2.8 and 2.9 in the work of B. Gorfinkel. “Sign-synthesizing electronics: low-voltage cathodoluminescence.” Publishing House of Saratov University, 1993, pp. 19-21, 24-25.

The complexity of the tip structure of the cathodes substantially complicates the implementation of this display.

It was previously established that when an electric current passes through thin metal films with an island structure several tens of thickness (from 40 to 80 for gold) the Angstrom generates an emission current due to the fact that some of the electrons carrying out charge transfer between the metal islands in the film have the velocity component normal to the film surface (see discovery No. 31, publ. 12/01/1964, authors of the discovery: P.G. Borzyak, O.G. Sarbey, R.D. Fedorovich). The authors discovered two phenomena in metals, which are gaining practical application in the field of microelectronics. Their experiments found that cold metal can emit electrons when current passes through it.

The closest analogue prototype to the invention is a cathodoluminescent screen (see RF patent No. 2152662, MKI ⁷ : HO1J 1/62, 29/18, publ. July 10, 2000), containing a vacuum shell composed of two flat glass transparent front plates and substrates with electrodes: a flat thin end emitter and an anode coated with a conductive layer and a phosphor, forming a light-emitting pixel cell located at a small controlled distance from each other in parallel planes connected through the anode and emitter buses to the output for connecting voltage sources, a dielectric frame hermetically connecting the front plate and the substrate, the anodes and emitters are made in the form of two combs, nested one into the other, with emitters with connectors located in the upper plane of the substrate, and the anodes and anode buses are located at the bottom trenches made to a predetermined depth in the substrate from the side of the upper plane, and the free space of the trenches of the anode bars is filled with a dielectric to form a planarized surface for her connecting bus. Anodes and emitters can be made in the form of any geometric figures embedded one into another, for example, in the form of spirals; a protective resistance is additionally introduced into the cathodoluminescent screen, connecting the emitter bus in series with each emitter of the light-emitting pixel cell; phosphor selected with submicron grains; the phosphor is selected low voltage with an operating voltage of not more than 50-70 V.

The disadvantage of this design is the presence of a complex system of emitter electrodes, while they are located in such a way that they reduce some parameters of the cathodoluminescent screen: viewing angle and information content of the screen.

The listed disadvantages of the claimed technical solutions are eliminated.

The invention consists in the following. The problem to which the invention is directed, is to simplify the processes in the manufacture of a matrix cathodoluminescent screen with an auto-electronic cathode, in ensuring its higher functional parameters.

The specified technical result during the implementation of the invention is achieved by the fact that in the known cathodoluminescent screen with an autoelectronic cathode containing a vacuum shell composed of two flat glass front transparent plates and an anode plate with anode electrodes coated with a conductive layer and a phosphor of at least one color, matrix of electron emitters, a dielectric frame connecting the face plate to the anode plate, a matrix of surface-conducting electron emitters is formed on the face a transparent plate, wherein the electron emitters are located opposite the anode electrode along its perimeter, forming a light-emitting pixel cell, with the possibility of outputting the light emitted by the electrons in the phosphor on the anode electrode through the central face plate-free surface of the electron emitters, between the light-emitting pixel cells a black dielectric mask is located on the front transparent plate, and a dielectric mask on the anode board.

The specified technical result during the implementation of the invention is achieved by the fact that in the known cathodoluminescent screen with an autoelectronic cathode containing a vacuum shell composed of two flat glass front transparent plates and an anode plate with anode electrodes coated with a conductive layer and a phosphor of at least one color, matrix of electron emitters, a dielectric frame connecting the face plate to the anode plate, a matrix of surface-conducting electron emitters is formed on the face a transparent plate, wherein the electron emitters are located opposite the anode electrode, forming a light-emitting pixel cell, in the central part of the pixel coaxially with the anode electrode with the possibility of outputting light radiation excited by electrons in the phosphor on the anode electrode through the surface of the face plate free around the perimeter of the electron emitter, moreover, between the light-emitting pixel cells on the front transparent plate there is a black dielectric mask, and on the anode board there is a dielectric mask.

The application of the claimed technical solution allows the use of a matrix of electron emitters as a matrix of surface-conducting electron emitters.

The introduction of a black dielectric mask on the front transparent plate focuses the electron flow from the selected emitter to the anode electrodes and increases the image contrast.

The introduction of a dielectric mask on the anode plate improves the focusing of electrons.

The invention is illustrated graphic materials.

In figure 1. The general view of the matrix cathodoluminescent screen is shown in accordance with the proposed technical solution: the matrix of electron emitters is formed on the front transparent plate in the case when the electron emitters are located opposite the anode electrode along its perimeter.

Figure 2 shows a fragment of a matrix cathodoluminescent screen pixel, in which electron emitters are located opposite the anode electrode along its perimeter.

Figure 3 shows a General view of the matrix cathodoluminescent screen in accordance with the proposed technical solution: the matrix of electron emitters is formed on a glass front plate in the case when the electron emitters are located opposite the anode electrode in the Central part of the pixel coaxially with the anode electrode.

Figure 4 shows a fragment of a matrix cathodoluminescent screen pixel, in which electron emitters are located opposite the anode electrode in the central part of the pixel coaxially with the anode electrode.

In the drawings, the following notation:

1 - a vacuum shell of a matrix cathodoluminescent screen with an autoelectronic cathode;

2 - glass front transparent plate;

3 - anode plate;

4 - anode electrodes;

5 - conductive layer;

6 - phosphor of at least one color;

7 - electron emitters;

8 - pixel light-emitting cell;

9 - dielectric frame;

10 - conclusions;

11 - dielectric mask (black on the transparent front plate).

The work of the matrix cathodoluminescent screen is as follows.

The predetermined light-emitting cell-pixel 8 is turned on by applying voltage through the terminals 10 to the corresponding electron emitter 7 and the anode electrodes 4, which form the specified light-emitting cell-pixel 8. The electrons emitted from the electron emitters 7 are scattered evenly over the area of the anode electrode 4. In this case, under the influence of an electric field concentrating on the surface of conductive electron emitters 7, electron emission occurs, the current of emitted electrons can be directed to the anode electrode 4. Under the influence of electronic bombardment, the light emitting cell-pixel 8 is illuminated.

In the first technical solution, the radiation generated by electrons in the phosphor 6 on the anode electrode 4 is output through the Central free surface of the front transparent plate 2 (see figure 1, 2).

In the second technical solution, the radiation generated by the electrons in the phosphor 6 on the anode electrode 4 is output through the surface of the front transparent plate 2, which is free around the perimeter from the emitter (see Figs. 3, 4).

The manufacturing technology of matrix cathodoluminescent screens is self-aligned, which ensures automatic placement of electron emitters and anode electrodes on top of each other: in one embodiment, the electron emitter is located opposite the anode electrode along its perimeter (see figure 2), and in the other, each of the electron emitters is located opposite the anode electrode in the Central part of the pixel coaxially with the anode electrode (see figure 4).

The inventive device can be manufactured by serial production of the matrix cathodoluminescent screen.

The operability of the claimed devices is experimentally confirmed: at present, the proposed designs of matrix cathodoluminescent screens are made and tested.

The data of the invention make it possible to obtain matrix cathodoluminescent screens providing reliable reading of information, a clear image, which is especially important for systems with a large working area and high information density.

Claims (2)

1. Matrix cathodoluminescent screen with an auto-electronic cathode, containing a vacuum shell composed of two flat glass front transparent plates and an anode plate with anode electrodes coated with a conductive layer and a phosphor of at least one color, a matrix of electron emitters, external terminals for connecting the anode electrodes and emitters of electrons with an electric voltage source, a dielectric frame connecting the face plate to the anode plate, characterized in that the surface-matrix driving electron emitters is formed on the face plate, while the electron emitters are located opposite the anode electrode along its perimeter, forming a light-emitting pixel cell, with the possibility of outputting the light emitted by the electrons in the phosphor on the anode electrode, through the central face plate-free surface of the electron emitters, moreover, between the light-emitting pixel cells on the front transparent plate there is a black dielectric mask, and on the anode board there is a dielectric baby mask. 2. A matrix cathodoluminescent screen with an autoelectronic cathode, containing a vacuum shell composed of two flat glass transparent front plates and an anode plate with anode electrodes coated with a conductive layer and a phosphor of at least one color, a matrix of electron emitters, external terminals for connecting the anode electrodes and emitters of electrons with an electric voltage source, a dielectric frame connecting the face plate to the anode plate, characterized in that the surface-matrix of the driving electron emitters is formed on the face plate, while the electron emitters are located opposite the anode electrode, forming a light-emitting pixel cell in the central part of the pixel coaxially with the anode electrode with the possibility of outputting the radiation of light excited by the electrons in the phosphor on the anode electrode through the free perimeter from electron emitters the surface of the face plate, and between the light-emitting pixel cells on the front transparent plate is a black dielectric mask, and a dielectric mask is located on the anode board.

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