JPH0254840A - Image display device - Google Patents

Abstract

PURPOSE:To suppress the vibration of cathodes and stabilize generated beams by fitting coil or pipe-shaped dampers on end sections of stretched linear cathodes. CONSTITUTION:Stretching springs 3 and fixing tools 4 of cathode wires 5 are stuck on both the upper end lower sides of scanning electrodes on a glass plate 1. Wire rods coated with an oxide cathode material on W wires are stretched by the springs 3 and fixing tools 4. Dampers 6 made of a W fine coil are provided on both ends of the cathode wires 5. Position fixing tools 7 are provided apart from the cathode wires 5 via insulators to prevent the movement of the inserted coil or pipe-shaped dampers. The dampers are provided outside the image display region. The vibration of the cathode wires is suppressed, thereby generated electron beams are stabilized.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a flat image display device used in color television receivers, computer terminal displays, and the like.

2. Description of the Related Art Recently, thin display devices have been widely used in the field of displaying images, characters, and the like.

An example of such a thin display device is a flat picture tube.

The present applicant previously proposed a flat picture tube in Japanese Patent Application Laid-open Nos. 189848-1989 and 193242-1980.

The configuration will be explained below with reference to FIG. This flat picture tube actually has each electrode built into a glass container, which is a vacuum envelope, but the vacuum envelope is omitted except for some parts in the figure to make the internal electrodes clear. are doing. Further, in order to clarify the horizontal and vertical directions of the screen on which images, characters, etc. are displayed, a horizontal direction H and a vertical direction Y are illustrated on the face plate portion. A plurality of vertically long linear cathodes 101 are arranged independently at equal intervals, and each of the linear cathodes 101 has an oxide cathode material formed on the surface of a tungsten wire. The number of linear cathodes 101 and the interval at which they are arranged are arbitrary. For example, if the display screen size is 10 inches, the interval at which they are arranged is 10 nyn, and 20 linear cathodes 101 are approximately 160 m in the vertical direction. It is arranged with a length of . Linear cathode 1
A face plate part 10 which is a screen part separated from 01
2, and a vertical scanning electrode 10 adjacent to the linear cathode 101.
3 are arranged to sandwich the linear cathode 101. The vertical scanning electrodes 103 are elongated in the horizontal direction, have equal pitches, are electrically divided, and are supported on an insulating support 104. These vertical scanning electrodes 103 are formed as independent electrodes having the same number of horizontal scanning lines in the vertical direction (approximately 480 in the NTSC system) if, for example, a normal television image is to be displayed. Note that the vertical scanning electrode 10
3 may be l/n of the number of horizontal scanning lines.

Between the linear cathode 101 and the face plate 102, a first grid electrode (
(hereinafter referred to as the G1 electrode) 105, a second grid electrode (hereinafter referred to as the Qt electrode) 106, a third grid electrode (hereinafter referred to as the Qs electrode) 107, and a fourth grid electrode (hereinafter referred to as the G4 electrode) 108 are arranged. There is no particular limit to the number of electrodes. G1 electrode 105 to G4 electrode 1
Each of the electrodes up to 08 is provided with an opening in a portion corresponding to the linear cathode 101 through which the electron beam passes.

The G1 electrode 105 is electrically divided into individual linear cathodes 101, and a video signal is applied to each electrode to perform beam modulation for each linear cathode 101.

The Qt electrode 106 to the G4 electrode 108 are planar electrodes that extract the electron beam or optimize the beam spot diameter in the horizontal and vertical directions. G
Between the four electrodes 108 and the face plate 102, horizontal deflection electrodes 113A, 113B, and 113C are arranged so as to sandwich the straight axis of electron beam from each linear cathode 101 and at the same spacing as the linear cathode spacing.

Each horizontal deflection electrode 113A, 113B.

113C is one in which a conductive film is formed on the surface of an insulating support 1140 by plating, vacuum deposition, or the like. An optimal DC voltage for optimizing the horizontal spot diameter of each electron beam and a deflection voltage for horizontally deflecting each electron beam are applied to each of the horizontal deflection electrodes 113A, 113B, and 113C. A light emitting layer consisting of a phosphor 115 and a metal back electrode 116 is formed on the inner surface of the face plate 102 .

The phosphor 115 sequentially spreads the field (R) in the horizontal direction during color display.
), green (G), blue (B) stripes or dots.

Next, the operation of the flat picture tube described above will be explained. First, a current is passed through the linear cathode 101 to heat it, and the G
Approximately the same voltage as the linear cathode is applied to one electrode 105 and one vertical scanning electrode (one horizontal scanning line). At this time, the electron beam advances from the linear cathode 101 toward the G1 electrode 105 and the Gt electrode 106, and each electrode
A voltage higher than the potential of the linear cathode 101 (1
00 to 500 cm) is applied to the G2 electrode 106. Here, the electron beam can be controlled by applying a potential more negative than the potential of the linear cathode 101 to the G1 electrode 105. The electron beam passing through the aperture of the G electrode 106 is transferred to the G electrode 107, the G4 electrode 108, and the horizontal deflection electrodes 113A and 113B that face each other with the electron beam in between.
, 113C, a predetermined voltage is applied to these electrodes so that the electron beam becomes a spot with a small diameter on the fluorescent surface. Here, horizontal deflection electrodes 113A, 113B,
113C, individual DC voltages are applied to obtain the best spot diameter, and at the same time, a sawtooth, stepwise, or triangular deflection voltage synchronized with horizontal scanning is superimposed, and each electron beam is is deflected horizontally by a predetermined width. The deflected electron beam collides with the phosphor 115 to form a luminescent image on the screen. At this time, in order to obtain a color image, etc., when each electron beam horizontally scans the phosphor 115 as described above, each color is applied to the G1 electrode corresponding to the phosphor of each color on which the electron beam is incident. It is sufficient to apply a modulation signal of

In addition, vertical scanning in this method is performed using one vertical scanning electrode 103 provided on the back surface of the linear cathode 101.
Vertical scanning can be performed by sequentially applying a potential to the book from the top so that an electron beam is generated on the phosphor 115 side for one horizontal scanning period (IH).

Problems to be Solved by the Invention However, the above configuration is good when the screen to be displayed has a small area, but as the area increases, the linear cathode becomes longer and the linear cathode and vertical scanning electrode become longer. It is difficult to maintain the distance between the G1 and G1 electrodes uniformly over the entire area. Furthermore, as shown in FIG. 4, the linear cathode 101 is fixed on an insulating support 104 provided with a vertical scanning electrode 103 by means of welding or the like at one end to a fixing pedestal 20, and at the other end. is stretched by a spring 21 and arranged at a constant distance from the vertical scanning electrode 103.

The linear cathode 101 is made of a thin metal wire with a diameter of 10 to 50 μm coated with an oxide cathode material, and because both ends are supported and float in space, mechanical vibrations are likely to occur. As a result, the linear cathode 101 and the vertical scanning electrode 1
03 or G1 electrode will occur, and the linear cathode 101 will be damaged. Furthermore, the vibration of the linear cathode 101 heats the linear cathode 101 and destabilizes the amount of electrons generated, resulting in brightness noise on the screen.

The present invention is intended to solve the above problems, and aims to suppress the generation of vibrations in a linear cathode and quickly stop the generated vibrations.

Means for Solving the Problems The present invention achieves the above object by providing a coil-shaped or pipe-shaped damper at the end of the stretched linear cathode, with the linear cathode passing through it. do.

Effect of the Invention With the above-described configuration, the present invention can minimize the occurrence of mechanical vibrations in the linear cathode used in flat cathode ray tubes, display tubes, etc., and at the same time, shorten the stop time even if vibrations occur. This makes it possible to reduce the occurrence of image flickering on the screen.

Examples Examples of the present invention will be described below with reference to the drawings.

FIG. 1 is a partial perspective view of a linear cathode of an image display device according to an embodiment of the present invention.

In FIG. 1, 1 is an insulating support such as a glass plate, and 2 is a vertical scanning electrode provided on this insulating support 1. In FIG.

A spring 3 , a fixture 4 , and a position fixture 7 are provided on both upper and lower sides of the vertical scanning electrode 2 . 5 is a linear cathode, and 6 is a coil damper provided so as to pass through the linear cathode 5.

In the above configuration, the structure will be explained in more detail below.

A vertical scanning electrode 2 is provided on an insulating support 1 such as a glass plate for switching an electron beam in a direction perpendicular to the screen. The vertical scanning electrode 2 is made of a transparent conductive film or a metal film, and is formed to be elongated in the horizontal direction of the screen and divided at a predetermined pitch in the vertical direction by means of screen printing, photoetching, or the like. On the insulating supports 1 at both the upper and lower ends of the vertical scanning electrode 2, springs 3 and fixtures 4 for stretching the linear cathode 5 are fixed with an adhesive (for example, low melting point glass). The linear cathode 5 is
A tungsten wire whose surface is coated with an oxide cathode material is used, and is fixed to a spring 3 and a fixture 4 and stretched with a predetermined distance from the vertical scanning electrode 2. Here, coil dampers 6 are provided at both ends of the linear cathode 5 so as to allow the linear cathode 5 to pass therethrough. The coil damper 6 uses a thin wire such as tungsten wire or tantalum wire with a diameter of about 0.1 nwn, an inner diameter of about 1 mm, and a coil of about 20 turns. next,
In order to prevent this coil damper 6 from moving on the linear cathode 5, a position fixing device 7 is provided on the insulating support 1. This position fixing device 7 is made of metal or an insulating material, and is provided at a predetermined distance from the linear cathode 5 to prevent the coil damper 6 from moving onto the vertical scanning electrode 2 portion. There is. The coil damper 6 is
It is desirable to install it outside the image display area so as not to affect the electron beam that forms the image.

Next, the operation of the above embodiment will be explained using FIG. 2. In FIG. 2, a predetermined voltage is applied to the linear cathode 5 and the vertical scanning electrode 2, and the linear cathode 5 is connected to the linear cathode 5.
The graph shows the results of applying a signal at a frequency at which the linear cathode 5 vibrates (resonant frequency) and examining the relationship between the vibration amplitude of the linear cathode 5 and the weight of the coil damper. As a result, when the coil damper was not installed, a vibration amplitude of 200μm was generated, but when the coil damper 6 was installed, the weight was reduced to 15μm.
By doing the above, it was possible to reduce the vibration amplitude to about 20 μm or less, which was 1/10 or less compared to the case described above.

Note that the coil damper 6 does not have to be coil-shaped, and the same effect could be obtained even if a pipe-shaped one having the same content was used. Moreover, the damper 6 may be provided only at one end of the linear cathode.

Effects of the Invention As described above, the present invention uses a linear cathode and also provides a coil-shaped or pipe-shaped damper at the end of the stretched linear cathode in an image display device. By passing it through the linear cathode and attaching it, vibration of the linear cathode can be suppressed. As a result, the electron beam generated from the linear cathode can be stabilized.

In the second aspect of the present invention, since the damper is provided in a portion outside the effective part of the image display section, the damper itself is able to absorb the electrons generated from the linear cathode and which are not used to form the screen.
There will be no negative impact.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a linear cathode portion of an image display device according to an embodiment of the present invention, FIG. 2 is a graph showing data for explaining the effects of the device, and FIG. 3 is a conventional flat-type cathode. FIG. 4 is a perspective view of the overall configuration of a cathode ray tube. FIG. 4 is a perspective view of the configuration of a linear cathode portion of a conventional flat cathode ray tube. DESCRIPTION OF SYMBOLS 1... Insulating support body, 2... Vertical scanning electrode, 3...
Spring, 4... Fixture, 5... Linear cathode, 6...
・Coil damper, 7...Position fixing device, Name of agent: Patent attorney Shigetaka Awano and 1 person 1 Figure 5 Seasonal certificate cathode No. 2 Figure ko'〔L'ヲ゛：Reno\'-3FiL ) / 4 Fixtures 1 Holding body Fig. Q7 1 (J

Claims (3)

[Claims] (1) A linear cathode is stretched in a vacuum container, and a coil-shaped or pipe-shaped damper is provided at the end of the stretched linear cathode, with the linear cathode passing through it. An image display device characterized by: (2) The image display device according to claim 1, wherein the damper is attached to the linear cathode at a position outside the image display area. (3) The image display device according to claim 1, wherein the position fixing device for regulating the position of the damper is provided without contacting the linear cathode.