JPH0736621B2 - Flat panel image display device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flat panel image display device used in a television or the like, and more particularly to a flat panel image display device in which an image screen is divided.

2. Description of the Related Art As a conventional flat panel image display device, for example, Japanese Patent Laid-Open No. 60-1
It is disclosed in Japanese Patent Laid-Open No. 89848 and Japanese Patent Laid-Open No. 61-121682.

FIG. 4 (a) is a perspective view of a conventional flat panel image display device, in which 401 is divided into a plurality of band blocks, and phosphors of three primary colors of red, green and blue are horizontally arranged in stripes. Image screen, 402 arranged in sequence
Is a phosphor coated on the image screen, 403 is a horizontal deflection electrode having the same number of pairs of band blocks as that for horizontally deflecting the electron beam, 404 is a glass substrate supporting the horizontal deflection electrode 403, and 405 is horizontal. Direction, the linear cathodes that emit electrons as long as the number of band blocks arranged at equal intervals independently in the vertical direction, 406 is a grid that controls the electron beam from the linear cathode 405, and 407 is the linear cathode 4
It is a vertical scanning electrode which is provided close to the linear cathode 405 in the direction opposite to the image screen 401 with the line 05 interposed therebetween, and which is used to perform a slender vertical scanning in the electrically divided horizontal direction. The same number as the number is provided.

Note that the horizontal direction H and the vertical direction V are shown in order to clarify the horizontal and vertical directions of the screen. FIG. 4 (b) is an enlarged view of the image screen showing the coating pattern of the phosphor of the same device.

FIG. 5 is a block diagram of a signal processing unit for displaying an image of a conventional flat panel image display device.
1 is an input image signal, 102 is an A / D converter for A / D converting the image signal, 103 is a memory for storing the image signal for each band block, 106 is the D for the image signal from the memory This is a drive circuit for converting / A and driving the linear cathode 405.

In the flat panel image display device configured as described above, depending on the potential of the vertical scanning electrode 407 with respect to the linear cathode 405, the direction of the grid 406 from a certain portion in the vertical direction of the linear cathode 405 that has been preheated. An electron beam is emitted according to the image signal applied to the linear cathode 405. The emitted electron beam is accelerated by the grid 406 and, at the same time, is narrowed down through the openings provided in the grid 406 and advances toward the image screen 1.

Thus, the number of linear cathodes 405, grids 406, and vertical scanning electrodes 407 is the same as the number of vertical scanning electrodes in the vertical direction.
In the horizontal direction, the same number of electron guns as the number of band block divisions are configured. The electron beam from the electron gun is horizontally scanned by the horizontal deflection electrode 403 which is driven by a deflection waveform such as a sawtooth wave, and then causes the phosphor to emit light to display an image on the image screen 401.

It should be noted that the electron beams from the respective electron guns are simultaneously emitted in the same line in the horizontal direction, and since the horizontal deflection electrodes provided on the same glass substrate can be applied with the same electric potential structurally, they are adjacent to each other. In the band block, the deflection directions are reversed.

Next, a method of processing the image signal of the device will be briefly described. The image signal 101 of each primary color that is input is first of all an A / D converter
A / D conversion is performed by 102. The A / D-converted image signals of the respective primary colors are rearranged according to the arrangement of the phosphors applied to the image screen 401, and are sequentially written in the memory 103 for each band block. Further, the image data written one horizontal scanning time ago is simultaneously read from the plurality of memories 103 for each band block, and as described above, the band blocks display images in parallel on the same line in the horizontal direction. It will be.

However, in the above-mentioned configuration, since the deflection directions of the electron beams are different in the adjacent band blocks, an error in color reproduction occurs due to various factors in each band. In that case, the generation method differs between adjacent band blocks. For example, when the image data is output with a delayed timing, when a single green color is displayed as an image, a certain band block also causes the red phosphor to emit light, and the yellowish green color is displayed next to it. In the band block, the blue phosphor is also made to emit light, resulting in a light greenish state.
As a result, a striped pattern having the width of the band block occurs on the entire image screen, and even if a slight error in color reproduction occurs, there is a problem that the connection between the image screens is felt.

In view of the above point, the present invention has an object to provide a flat panel image display device that eliminates the feeling of band joining due to the difference in the deflection direction between adjacent band blocks.

Means for Solving the Problems According to the present invention, the phosphors are applied in reverse order between adjacent band blocks, and phosphors b of a predetermined color are provided between the band blocks.
With a 2 stripe width applied image screen,
The flat panel image display device includes a color detection circuit that detects the color of the edge of each band block and a data generation circuit that creates data for causing the phosphor b to emit light in accordance with a control signal from the color detection circuit.

Action According to the present invention, since the arrangement of the phosphors a is reversed between the adjacent band blocks, the relationship between the deflection direction and the coating arrangement of the phosphors is the same in each band block, so that the deflection directions are opposite. Therefore, there is no sense of the seam of the band due to the difference in how the color reproduction error occurs.

In addition, the color reproduction, the error, and the discontinuity of the brightness generated by reversing the arrangement of the phosphors a are also caused by the color of the phosphor a at the end of each band block and the color of the phosphor b between the band blocks. It is possible to make it difficult to feel by generating the data for making the phosphor b emit light by referring to the surrounding colors.

Embodiment 1 FIG. 1 is a block diagram showing an image signal processing circuit of a flat panel image display device according to a first embodiment of the present invention. 101 is an input image signal, 102 is an image signal
A / D converter for A / D conversion, 103 is a memory that stores an image signal for each band block, 104 is a color detection circuit that determines the color of the image from the data stored in the memory, 105
Is a data generation circuit that generates data for causing the phosphors between the band blocks to emit light according to a control signal from the color detection circuit. Reference numeral 106 is a D or image signal from the memory or the data generation circuit.
This is a drive circuit for converting / A and driving the linear cathode 405.

FIG. 2A is an enlarged view showing the coating state of the phosphor on the image screen of the flat panel image display device according to the first embodiment of the present invention. In FIG. 2, 201 is a phosphor a of three primary colors applied in stripes in each band block, and 202 is a phosphor b of a predetermined color between each band block.

The operation of the flat panel image display device of this embodiment constructed as described above will be described below. The image signal 101 of each primary color is A / D converted by the A / D converter 102 and rearranged according to the arrangement of the phosphors on the image screen,
The data is sequentially written in the memory 103 corresponding to each band block. Also. Image data written one horizontal period before is simultaneously read from the memory 103 from each memory, the drive circuit 106 drives each linear card using the data, and each band block displays an image in parallel. Let The above operation is similar to that described in the conventional example.

At this time, due to the structure of the flat panel image display device, the deflection directions are reversed in the adjacent band blocks.
If the coating order is the same, the connection of the band blocks is raised as described above. In order to prevent this, the arrangement of the phosphors a may be reversed between the band blocks as shown in FIG. 2 (b).

By doing so, the relationship between the deflection direction of the electron beam and the coating order of each phosphor can be made the same in each band block. As a result, in the case where the timing of outputting the image data is wrong, even if the position on the image screen 401 in the adjacent band block is wrong in the opposite direction, the order of applying the phosphors is reversed. For example, if a band block is shifted toward the red phosphor, it is also shifted toward the red phosphor in the adjacent band block, so that the color reproduction error occurring in each band block is adjacent. Almost the same occurs between band blocks. That is, it is possible to make it difficult to feel the joint between the band blocks due to the difference in color reproduction error, which is caused by the different deflection directions.

However, if the arrangement of the phosphors a201 is simply reversed as shown in FIG. 7B, the green phosphors are adjacent to each other at the joint of the band blocks, so only that part becomes a strong green color. Even when white is displayed on the entire screen, color reproduction is disturbed only in that part, and a thin green line is generated. When the number of divisions of the image screen is small, the generation of the thin line is not a serious problem, but when the number of divisions is increased, it becomes a problem. Therefore, as shown in FIG. 3A, a space is provided between the band blocks and the purple phosphor b is applied thereto. By doing so, the green phosphors, which are most sensitive to the brightness, are arranged at equal intervals, so that no line in which the brightness changes occurs even at the joints of the band blocks. Further, by arranging the purple phosphor b, which becomes white by combining with the green phosphor a, next to the green phosphor, it is possible to suppress the color reproduction error to the minimum. The image data for causing the purple phosphor b to emit light is detected by the color detection circuit 104 based on the data stored in the memory 103, and the data generation circuit 105 based on the color information and the luminance information. Created by.

As described above, according to the present embodiment, the coating order of the phosphor a is reversed in each band block, the space between each band block is widened between the two phosphors, and the color of the phosphor at the end of the band block is set there. By arranging the phosphor b according to the above, it is possible to suppress the discomfort between the band blocks due to the difference in the color unevenness occurring in the band blocks, that is, the feeling of the joint between the band blocks.

FIG. 3 is an enlarged view showing the coating state of the phosphor on the image screen portion of the flat panel image display device according to the second embodiment of the present invention, and 201 indicates the phosphor a coated in the band block. And is the same as that shown in FIG. 203 is the phosphor a applied between the band blocks.
Is a phosphor c having a width half that of the above.

The operation of the flat-panel image display device of the second embodiment constructed as described above will be described below.

The image signal processing in this embodiment is similar to that in the first embodiment. The difference from the first embodiment is that instead of the mixed color phosphor b between the band blocks, a primary color phosphor c having a half width is applied in two colors so as to be the same color as the color of the phosphor b. That is. By doing this, it is possible to minimize the occurrence of luminance or lines that change color by connecting the band blocks even in the case of single-color display of red or blue, or in other mixed-color display. The joints of the band blocks become less noticeable, and a better image can be displayed.

As described above, according to the present embodiment, by applying two primary color phosphors instead of mixed color phosphors, it is possible to suppress the feeling of seams between band blocks due to color unevenness occurring in the band blocks. As well as
Better color reproduction for all colors.

Although the phosphors at the ends of the band blocks are green phosphors in the first and second embodiments, the same applies to red and blue, and the phosphors b at that time are cyan and yellow, respectively. .

EFFECTS OF THE INVENTION As described above, according to the present invention, color reproduction in each band block which is unavoidable in the structure of the flat panel image display device and which occurs due to the difference in the deflection direction of the electron beam of each adjacent band block Eliminates differences between adjacent band blocks, resulting in almost the same color reproduction quality for each band block, smooth band block connection, and no connection between band blocks. A flat panel image display device capable of displaying better images can be realized, and its practical effect is great.

[Brief description of drawings]

FIG. 1 is an image signal processing block diagram of a flat panel image display apparatus according to the first embodiment of the present invention, FIG. 2 is an enlarged view showing a phosphor coating state of an image screen in the simultaneous embodiment, and FIG. FIG. 4 (b) is an enlarged view showing the phosphor coating state of the image screen in the second embodiment of the present invention, FIG. 4 (a) is a perspective view showing the structure of the flat panel image display device, and FIG. 4 (b).
FIG. 5 is an enlarged view showing a phosphor coating state of an image screen of a conventional flat panel image display device, and FIG. 5 is a block diagram showing an image signal processing block of the conventional flat panel image display device. 101 …… image signal, 102 …… A / D converter, 103 …… memory,
104 ... Color detection circuit, 105 ... Data generation circuit, 201 ...
Phosphor a, 202 ... Phosphor b, 203 ... Phosphor c, 401 ...
… Image screen, 402… Phosphor, 403… Horizontal deflection electrode, 404… Glass substrate, 405… Linear cathode, 406…
… Grid, 407… Vertical scan electrode.

Claims (2)

[Claims] 1. Red, green, which is divided into a plurality of band blocks in the horizontal direction and is sequentially applied in a vertical stripe pattern,
An image screen in which the phosphors a for each primary color of blue are arranged in the reverse order for each band block, and phosphors b of a predetermined color other than the primary color are applied in two stripes between the band blocks; An electron gun for emitting a common electron beam to each of the phosphors a and phosphors b of each color provided in each band block, and a plurality of horizontal deflection electrodes for deflecting the electron beam emitted from the electron gun. ,
A / D converter for A / D converting the image signal, a plurality of memories for storing the image signal from the A / D converter for displaying each band block, and at least a band of the data in each memory A color detection circuit that determines the colors of the image signals at both ends of the block, a data generation circuit that creates image data that causes the phosphor b of the image screen to emit light according to a control signal from the color detection circuit, and data from the memory. And a drive circuit for D / A converting image data from the data generating circuit to drive the electron gun. 2. The phosphor b between each band block is half the width of the phosphor a in the band block, and phosphors of two primary colors of three primary colors are applied in a predetermined order in four stripes. The flat panel image display device according to claim 1, further comprising an image screen.