JPH02121234A - Image displaying device - Google Patents

Abstract

PURPOSE:To make it possible to obtain a white balance by applying carbon black preliminarily in a desired area in desired phosphor in a part where phosphor of the three primary colors, red, green and blue are to be applied in stripes, and making the phophor areas of the three primary colors in spite of the same stripe width of phosphor. CONSTITUTION:Carbon black 17 is applied for a desired area in desired phosphor in a part where phosphor of three primary colors of red, green and blue in stripes in a screen to which an electron beam is radiated, so the three primary colors have the same phosphor stripe width but different phosphor areas. That is, prior to application of a green color G phosphor stripe 11, the carbon black 17 is applied in the form of grains in a desired quantity preliminarily. Light emission of the green color is thus restricted, and a white balance can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention generates an electron beam for each division when a screen is vertically divided into a plurality of divisions, and generates an electron beam for each valley division. The present invention relates to a phosphor surface for a device that displays a plurality of lines by vertically deflecting a beam to display a televised image as a whole.

Conventional technology Traditionally, cathode ray tubes have been mainly used as display elements for displaying color television images, but conventional cathode ray tubes have a very long depth compared to the screen size, making it difficult to use for thin TVs. It was impossible to create a John receiver. Furthermore, although EL display elements, plasma display devices, liquid crystal display elements, and the like have recently been developed as flat display elements, all of them are insufficient in terms of performance such as brightness, contrast, and color display.

Therefore, Japanese Patent Application No. 56-20618 (Japanese Unexamined Patent Publication No. 57-571) proposed a method for achieving a flat display device using electron beams.
135590), a new display device was proposed.

This is; when the screen is divided vertically into multiple sections, an electron beam is generated for each section, and each electron beam is deflected vertically for each valley section to display multiple lines. However, it displays a television image as a whole.

However, the above-mentioned image display device has a complicated structure, and it has been difficult to put it into practical use due to the high precision required in the assembly process, high material cost, and basic performance. Therefore, the present applicant proposed an image display device with a new structure in order to solve the above problems.

This is superior in that it has a simpler electrode structure than the previous image display device, and each electrode works very well for its own purpose and does not have much effect on other things.

This will be briefly explained below using figures.

FIG. 3 shows a basic configuration example of an image display element used in the present invention. In the figure, 1 is a back electrode, 2 is a line cathode as a beam source, and 3 is a beam extraction electrode, and the electron beam is guided to the front by the potential relationship of the three electrodes. Reference numeral 4 denotes a beam flow control electrode, which is divided into a plurality of electrodes in the horizontal direction so as to control the amount of light emitted from the valley pixels. The electron beam whose emission amount is controlled by the beam flow control electrode 4 is focused to a desired beam size by the focusing electrode 6, and is then focused to the desired beam size by the horizontal deflection electrode 6. By the vertical deflection electrode 7, the horizontal direction,
It is deflected in the vertical direction and illuminates the phosphor on the screen plate 8 to form a raster. The rasters are arranged well on the screen board 8 according to each control signal generated from the video signal, and one image is displayed as a whole.

The image display device of the present invention irradiates a phosphor with a strong electron beam for a short time to obtain a raster, and unlike a cathode ray tube, which expresses an image by the intensity of the electron beam, the image display device emits a weak electron beam for a long time. The body is irradiated to obtain a raster, and the irradiation time is controlled to express the image. Therefore, due to the above-mentioned difference in driving conditions, if the same phosphor as the cathode ray tube is used, the ratio of luminous efficiency of the three primary colors will be distorted, making it impossible to maintain white balance. Therefore, it is necessary to adjust the white balance by changing the coating area of the phosphor.

Hereinafter, the fluorescent surface of a conventional image display device will be explained with reference to the drawings.

FIGS. 2A and 2B are a front view and a sectional view of the fluorescent surface of a conventional image display device. In the example shown in FIG. 2, in order to maintain white balance, the width of the black stripes 12 at both ends of the green G phosphor stripe 11 is increased to limit green light emission. Here, 13 is a red R phosphor stripe, 14 is a blue B phosphor stripe, 15 is a face plate, and 16 is a raster formed by an electron beam.

Problems to be Solved by the Invention However, with the above configuration, when the phosphor stripes are irradiated with the raster-shaped beam shown in FIG. 2, the red and blue phosphor stripes R and B are thick; While the same brightness can be obtained even if the raster moves horizontally, the green phosphor stripe G is thinner, so it has less horizontal intensity, and even if the raster moves a little horizontally, it will cause a black stripe. It will take a while. moreover,
In terms of mechanical precision, it is extremely difficult to match the positional relationship between the raster and the phosphor stripes on all phosphor surfaces, so it is necessary to make the brightness uniform across the phosphor surface only for green. The problem was that it became impossible to do so.

In view of the above-mentioned problems, the present invention provides a phosphor surface that can achieve white balance by changing the coating area of the phosphors while keeping the widths of the phosphors of the three primary colors constant.

Means for Solving the Problems In order to solve the above-mentioned problems, the fluorescent surface of the image display device of the present invention is coated with a cap in advance on the part where the phosphors of the three primary colors of red, green and blue are applied in stripes. /Black is applied to a desired phosphor in a desired area, so that the phosphor areas of the three primary colors are different even though the phosphor stripes are the same.

Function According to the present invention, with the above-described configuration, white balance can be achieved by coating a desired area of the phosphor with carbon black to reduce the luminous efficiency.

EXAMPLE Hereinafter, an example of the present invention will be described with reference to the drawings. FIGS. 1A and 1B are a front view and a sectional view of the fluorescent surface of an image display device according to an embodiment of the present invention.

In this embodiment, before applying the green G phosphor stripe 11 to maintain white balance, a desired amount of carbon black 17 is applied in advance in the form of particles. This limits green light emission and maintains white balance.

Therefore, white balance can be achieved by adjusting the amount of carbon black 17.

Although carbon black was applied in the form of particles in this example, the same effect can be obtained by applying it in horizontal stripes and changing the width in the vertical direction.

Effects of the Invention As described above, according to the present invention, the phosphor area is changed by three primary color phosphors while keeping the same phosphor strip width, so that the brightness of the entire phosphor surface can be maintained uniformly. You can maintain the white balance and display beautiful, natural-looking images.

[Brief explanation of the drawing]

1A and 1B are a front view and a sectional view of a fluorescent surface of an image display device according to an embodiment of the present invention, and FIG. 2A is a sectional view. B is a front view and a cross-sectional view of a fluorescent surface of a conventional image display device;
FIG. 3 is an exploded perspective view of an image display element used in the present invention. 11... Green phosphor stripe, 17...
...Cabbon black.

Claims (1)

[Claims] On the screen where the electron beam is irradiated, carbon black is applied to the desired phosphors in the desired area on the part where the phosphors of the three primary colors of red, green, and blue are to be applied in stripes, and the same phosphor stripe width is applied. An image display device characterized in that the phosphor areas of three primary colors are different in size.