RU2310946C1 - Cathodoluminescent screen disposed on active matrix substrate - Google Patents

Abstract

FIELD: display engineering; cathodoluminescent screens built on active matrix substrate to display not only universal alphanumeric data but also television and computer information.

SUBSTANCE: proposed cathodoluminescent screen which is disposed on active matrix substrate and has vacuum envelope incorporating face glass plate and bottom glass plate mounting active matrix substrate with dual-channel addressing system (X, Y) and control system for each of plurality of phosphor-covered light-emitting components of at least one color, as well as set of filamentary hot cathodes, glass frame tightly joining face and bottom glass plates is diode-type screen; ratio of distance between centers of filamentary hot cathode bases in set of filamentary hot cathodes to that between disposition planes of set of light-emitting components and set of hot cathodes meets following condition: 0.8 ≤ t_cb/x_c-a < 1.6, where t_cb is distance between centers of filamentary hot cathode bases in set of filamentary hot cathodes; X_c-a is distance between disposition planes of set of light-emitting components and set of filamentary hot cathodes; duty factor F_cb/t_cb meets following condition: 0.6 · 10^-2 ≤ F_cb/t_cb ≤ 1.6 · 10^-2, where F_cb is diameter of filamentary hot cathode base.

EFFECT: enhanced body of information, continuous brightness (absence of "washing-board" effect).

1 cl, 3 dwg

Description

The invention relates to indicator technology and can be used to create cathodoluminescent screens on an active matrix substrate, displaying not only universal signographic, but also television and computer information.

Over the past three decades, cathodoluminescent flat panel displays (VLI), developed and developed in the industry of Japan, Russia and South Korea, have found wide application in the world of indicator technology.

Displays (VLI) are characterized by high brightness and reliability in operation, they are used in household and special equipment to display universal information in various types of video terminal devices (VTU).

However, VLI displays, including the matrix type, display information with a low resolution: less (256 × 256), because the line scan adopted for their control limits the number of rows (columns) due to a sharp decrease in brightness with increasing rows (columns). In this regard, VLI cannot be used to display television and computer information with high resolution.

In recent years, developers of leading companies in the world information technology - (USA, Russia, South Korea) have directed their efforts at creating cathodoluminescent screens on an active matrix substrate (AM-VLI), which includes addressing systems and the equivalent of "internal" memory, providing quasistatic display operation mode with the highest information capacity (unlimited resolution) required to create television screens (TV) and personal computers (PC).

Currently, there are many patents and reports on the creation of active-matrix vacuum-luminescent indicators (AM-VLI) and their design features.

The main ones are:

- patent RU No. 2234762, MKI ⁷ : H01J 21/10, published on 08/20/2004;

- Journal "Electronic Industry", No. 8, 1995, article "Cathode-luminescent displays based on matrix auto-electronic cathodes and an active control substrate." Authors: B.I. Gorfinkel, E.V. Rusina, V.L. Frolov, A.I. Loginov, P.M. Lobach .;

- US patent No. 5736814, MKI: H01J 031/15, published on 04/07/1998;

- US patent No. 6392356, MKI: H01J 031/12, published May 21, 2002.

In 2004, Russia (FSUE "Research Institute" Volga ") completed the development and put into production a single-color cathodoluminescent flat-panel active-matrix vacuum fluorescent indicator (AM-VLI) - a display on the thermal cathode and a controlled silicon (Si) substrate to display universal information in VTU.

The resolution of this AM-VLI is small and amounts to (256 × 256) rows and columns.

Currently, FSUE NII VOLGA (Russia), together with Kopy-Tele (SorU-Tele, USA), is developing AM-VLI on an active matrix substrate containing (960 × 320) pixels to create full-color (RGB) ) displays for TV and PC.

However, the unresolved problem today is the creation of highly informative displays on the thermal cathode, including the active matrix control substrate, consisting in discontinuity, or rather lack of uniformity in brightness, in the areas of the phosphor located directly under the thermal cathodes and the areas between the thermal cathodes, called the effect of a washboard. The brightness between the cathodes is much lower.

The lack of uniformity of brightness across the display field creates a problem in providing a "gray scale" in both single-color and full-color displays for TV devices.

In US patent No. 6392356 it is proposed to ensure uniformity of brightness at any point by changing (controlling) the shape of the electron cloud emitted by thermionic cathodes, namely, on the upper transparent display panel from the inside (vacuum) side, a group of conductive transparent electrodes is formed - bands, for example, ITO alloy, which are oriented parallel to the thermionic cathodes.

When the corresponding voltage potential is applied to the bands of the region with a high electron density (the regions closest to the thermionic cathode are attracted / repelled in the direction of the regions with a low electron density (the regions farthest from the thermionic cathodes), equalizing the electron densities ensures the luminosity of the phosphors in different regions display.

In the article "Cathodoluminescent Displays Based on Matrix Autoelectronic Cathodes and an Active Control Substrate" by Gorfinkel, Rusina EV, Frolova VL, Loginova AP, Lobacha PM (see the journal "Electronic Industry", No. 8, 1995, pp. 5-7 - prototype) in AM displays on a silicon substrate to eliminate the brightness inhomogeneity, a design with the introduction of a cathode grid located between the planes of the AM substrate with anode segments is proposed and a system of thermionic cathodes.

However, the information volume of such cathodoluminescent screens is also limited by some electro-optical and structural factors.

The invention is as follows. The problem to which the invention is directed, is to increase the information volume, to ensure the continuity of the brightness of the glow (no "washboard" effect).

The specified technical result in the implementation of the invention is achieved by the fact that the known cathodoluminescent screen on the active matrix substrate containing a vacuum shell consisting of a front glass plate and a lower glass plate with an active matrix substrate with a dual-channel addressing system (X, Y) and with a control system for each of a plurality of light-emitting elements coated with a phosphor of at least one color, and a direct-heating thermal cathode system, a glass frame, hermetically connected yayuschuyu face and a bottom glass plate, is formed by a diode, wherein the ratio of the distance between the centers of the cores directly heated thermionic cathodes in the system directly heated thermionic cathodes to the distance between the planes of arrangement of the light emitting elements of the system and a directly heated thermionic cathodes system satisfies the following condition:

where t _kk is the distance between the centers of the cores of direct heat cathodes in the system of direct heat cathodes,

удовлетворяет условию:X _ka is the distance between the planes of the system of light-emitting elements and the system of direct-heating thermal cathodes, and the fill factor

satisfies the condition:

where Ф _kk is the core diameter of a direct-heating thermal cathode.

The invention is illustrated by graphic materials, an example of a specific implementation and description.

Figure 1 schematically shows a cathodoluminescent screen on an active matrix substrate, a direct view.

Figure 2 schematically shows a cathodoluminescent screen on an active matrix substrate, side view.

Figure 3 schematically shows a matrix of light-emitting elements X-Y.

In the drawings, the following notation:

1 - cathodoluminescent screen;

2 - a vacuum shell;

3 - front glass plate;

4 - lower glass plate;

5 - active matrix substrate located on the lower glass plate 4;

6 - light emitting elements;

7 - phosphor;

8 - direct heating thermal cathodes;

9 - two-channel addressing system (X, Y);

10 - column X-buses, for example, X ₁ , X ₂ , X ₃ , ..., X _n ;

11 - lowercase Y-buses, for example, Y ₁ , Y ₂ , Y ₃ , ..., Y _n ;

12 - semiconductor crystal on an active matrix substrate 5;

13 is a control system for each of a plurality of light emitting electrodes 4.

The cathodoluminescent screen on the active matrix substrate contains a vacuum shell 2 consisting of a front glass plate 3 and a lower glass plate 4 on which the active matrix substrate 5 is located. Inside the vacuum shell 2 on the active matrix substrate 5 there is a dual-channel addressing system (X, Y) 9 , a system of light emitting elements 6 coated with a phosphor 7 of at least one color, a control system 13 of each of a plurality of light emitting elements 6, and a system of direct heat cathodes 8.

The device operates as follows (see figure 1). The semiconductor crystal 12 is under positive voltage relative to the direct-heating thermal cathode 8, the magnitude of which is sufficient for the occurrence of cathodoluminescence on the light-emitting elements 6. On the lower-case Y-buses 11 (Y ₁ , Y ₂ , Y ₃ , ..., Y _n ), pulses are alternately applied, formed by the control system 13 by each of the plurality of light emitting elements 6. On the column X buses 10 (X ₁ , X ₂ , X ₃ , ..., X _n ,) pulses are alternately generated by the control system 13 by each of the plurality of light emitting elements 6. When availability built each element in the X-Y matrix of memory function is realized quasistatic mode information display method for dynamic addressing elements X-Y matrix, and the ability to display information from the analog scale gradation display mode is realized.

Phosphors 7 begin to glow under the influence of electronic bombardment. The light emitting elements 6, on which there is no accelerating potential, are not exposed to the electron beam, and the phosphors 7 remain in an unexcited state, i.e. all other screen elements do not light up.

Alternately illuminating in this way certain light-emitting elements 6 of the matrix screen, the desired image is obtained on the screen.

(от 0,6·10^-2 до 1,6·10^-2) определены экспериментально с учетом известных закономерностей, принятых при конструировании приборов.Figure 2 shows the distance t _kk between the centers of the cores of directly heated thermal cathodes 8, and Figures 1, 2 show the distance X _ka between the planes of the arrangement of the system of light-emitting elements 6; and direct-heated thermal cathode systems 8 and Ф _kk is the core diameter of the direct-heated thermal cathode 8. The ratio of the distance t _kk between the centers of the direct-heated thermal cathode cores 8 in the direct-heated cathode system to the distance X _k- between the planes of the system of light-emitting elements 6 and the direct-heated thermal cathode system 8 (from 0 , 8 to 1.6), as well as the fill factor

(from 0.6 · 10 ^-2 to 1.6 · 10 ^-2 ) are determined experimentally taking into account the well-known patterns adopted in the design of devices.

определяет:In this case, the fill factor

defines:

a) "transparency", "max" - the passage of light information from light-emitting elements through a system of direct-heating thermal cathodes;

b) the power consumption of the direct-heated thermal cathode system and ensures the absence of the “washboard” effect in the cathodoluminescent screens.

The use of this design of the cathodoluminescent screen on the active matrix substrate in comparison with the known designs can improve the quality of the displayed information by increasing the uniformity of the phosphor glow and eliminating the effect of "washboard".

Claims (1)

A cathodoluminescent screen on an active matrix substrate containing a vacuum shell consisting of a front glass plate and a lower glass plate with an active matrix substrate located with a two-channel addressing system (X, Y) and with a control system for each of the many light-emitting elements coated with a phosphor, at least , of the same color, and a direct-heating thermal cathode system, a glass frame tightly connecting the front and lower glass plates, characterized in that the cathodoluminescent screen and the active matrix substrate is made in diode design, and the ratio of the distance between the centers of the cores of the direct heating cathodes in the system of direct heating cathodes and the distance between the planes of the system of light-emitting elements and the system of thermal cathodes satisfies the condition:

where t _kk is the distance between the centers of the cores of direct heating cathodes in the system of direct heating cathodes; X _ka is the distance between the planes of the system of light-emitting elements and the system of direct-heating thermal cathodes, and the fill factor

satisfies the condition

where Ф _kk is the core diameter of a direct-heating thermal cathode.

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