JPS6382184A - Color display device - Google Patents

Abstract

PURPOSE:To improve the resolution of display and to reduce color arrangement noise by arranging green display picture elements in mosaic and arranging other colors alternately inbetween. CONSTITUTION:The green color display picture elements G are arranged in mosaic and the other color display picture elements R, B are arranged alternately inbetween to set the aperture rate of the green display picture elements to 1/2 of the aperture rate of the other color display picture elements. Since the green display picture elements are arranged in mosaic and the red and blue display picture elements are arranged alternately inbetween, then the display picture elements of the same color are not arranged in horizontal/vertical/ oblique directions and so-called color arrangement noise such as color stripe is not caused. Since the green display picture elements giving the largest effect onto the visual resolution are arranged in mosaic, the resolution of display is much improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a color display device for displaying color images using, for example, a liquid crystal display element.

[Summary of the invention]

The present invention relates to a color display device, in which green display pixels are arranged in a checkered pattern and other colors are arranged alternately between them, thereby improving display resolution and reducing color arrangement noise. be.

[Conventional technology]

For example, it has been proposed to display television images using liquid crystals.

In FIG. 5, (1) is an input terminal to which a television video signal is supplied, and the signal from this input terminal (1) is transmitted to each switching element M1. M2...Line L1 in the vertical (Y-axis) direction through Mm. L2...supplied to Lm. Note that m is a number corresponding to the number of pixels in the horizontal (X-axis) direction. Furthermore, a shift register (2) of m'IIt is provided, and this shift register (2) receives a clock signal Φ18. Φ2H is supplied and this shift register (2)
The drive pulse signal φH1+ φH is sequentially scanned by the crosshair signal φIJl+ φ2H from each output terminal of
2...φHm is supplied to each control terminal of the switching elements M'' to MI11. Note that the shift register (2) is supplied with a low potential (Vss) and a high potential (VDn), and drive pulses of these two potentials are formed.

In addition, each line L1 to Lm is provided with a switching element M11゜M2j... consisting of, for example, an N-channel FET.
Mn11M】21M22...Mn21...Mlm
, M2H...Mnm are connected to one end. Note that n is a number corresponding to the number of horizontal scanning lines. The other ends of these switching elements Mu to Mnm are respectively connected to liquid crystal cells Csx +
Connected to the target terminal (3) through C21...Cnm.

Furthermore, an n-stage shift register (4) is provided, and this shift register (4) receives a horizontal frequency clock signal ΦIV.
+ Φ2v is supplied, and drive pulse signals φVl, φv2 are sequentially scanned by clock signals ΦiVr Φ2v from each output terminal of this shift register (4).
...φvn is the gate line G1 in the horizontal (X-axis) direction. C
;2... Switching elements Mu to Mnm through Gn
Each row in the X-axis direction (M11 to Mtm) + (M21
~M2I11)... (Mi1~Mnm) are respectively supplied to the control terminals. In addition, shift register (4
) also has Vss and VDrl in the same way as shift register (2).
is supplied.

That is, in this circuit, a shift register (2).

(4) As shown in FIG. 6A and B, the lock signal ΦI
Hr Φ281 ΦtVt Φ2v is supplied. The shift register (2) outputs φH to φMm for each pixel period as shown in C in the same figure, and the shift register (4) outputs φv1 to φvn for each horizontal period as shown in the same figure. Output. Furthermore, the input terminal (1) is supplied with a signal as shown in FIG.

When φVi+φH1 is output, switching elements M1 and M11 to M1111 are turned on,
A current path of input terminal +1) → M1 → L1 → M11 → cti → target terminal (3) is formed, and the signal supplied to the input terminal (11) and the target terminal (3) are formed in the liquid crystal cell C1l.
) is supplied. Therefore, the charge corresponding to the potential difference due to the signal of the first pixel is sampled and held in the capacitance of this cell C1l. The light transmittance of the liquid crystal changes depending on the amount of charge. The same process is performed sequentially for the cells C12 to Cnm, and when the next field signal is supplied, the amount of charge in each of the cells C1t to Cnm is rewritten.

In this way, the light transmittance of the liquid crystal cells 011 to Cnm is changed corresponding to each pixel of the video signal, and this is sequentially repeated to display a television image.

By the way, when displaying with a liquid crystal, AC drive is generally used to increase its reliability and longevity. For example, in displaying a 1IHL image on a television, a signal obtained by inverting the video signal is supplied to the input terminal (1) for each field or frame. That is, the input terminal (1) is supplied with a signal that is inverted for each field or frame as shown in FIG. 6E.

By the way, in the above-mentioned device, the display can be colored by arranging color filters of different colors for each liquid crystal cell C and making the video signals supplied to the input terminal (1) the corresponding color signals. can. In this case, the pixel electrodes P of each liquid crystal cell C were conventionally arranged in alignment in the vertical and horizontal directions, respectively, as shown by broken lines in the figure.

Therefore, as a method of arranging color filters for the pixels (electrodes P) arranged in this way, the so-called stripe type as shown in FIG. ). In the figure, ■ indicates a red color filter, ■ indicates a green color filter, and ■ indicates a blue color filter.

However, in the case of such a striped color filter, the resolution in the horizontal direction is 1/3 that of a monochrome filter, resulting in extremely poor image quality.

In contrast, a so-called mosaic color filter as shown in FIG. 8 has also been proposed. In this case, the horizontal resolution is improved compared to the stripe type, but as is clear from the figure, because the color filters of the same color are arranged diagonally,
Diagonal color streaks appeared on the screen that looked like beat interference, and this severely degraded the image quality.

[Problem that the invention seeks to solve]

Conventional devices were constructed as described above. For this reason, conventional devices have had the problem of extremely poor image quality when colorizing images, such as low resolution of the outer layer and diagonal color distortion (so-called color alignment noise).

[Means for solving problems]

The present invention provides a plurality of first signal lines L1 . ．． L2 . . . Lm, and a plurality of second signal lines G1 . . . Lm arranged in parallel in the horizontal direction. G2...Gn are provided, and these first...Gn are provided. A selection element M11. is provided at each intersection of the second signal line. In a color display device in which pixel electrodes Psx, PI3...Pnm are provided via M12...Mnm, green display pixels @ are arranged in a checkered pattern, and display pixels 0■ of other colors are arranged in between. The color display device is characterized in that the green display pixels are arranged alternately so that the aperture ratio of the green display pixels is 1/2 of the aperture ratio of the display pixels of other colors.

[Effect]

According to this device, green display pixels are arranged in a checkered pattern,
Since display pixels of other colors are arranged alternately between them, diagonal color streaks do not occur even if a mosaic-type color filter is provided. The resolution is improved and extremely good image quality can be obtained.

〔Example〕

In Figure 1, green color filters ◎, which serve as green display pixels, are arranged in a checkerboard pattern, and red color filters ■ and blue color filters ■, which serve as display pixels of other colors, are arranged alternately between them. Ru. And the area of the green color filter O mentioned above (
The aperture ratio) is set to 1/2 of that of the other color filters.

Furthermore, FIG. 2 shows a specific circuit pattern of a liquid crystal display device corresponding to the above-mentioned arrangement of color filters O■■, in which vertical signal lines Lj and gate lines Gi are arranged in a zigzag pattern along the boundaries of each color filter. In addition, each vertical signal line L
A ゛ζ switching element Mij is formed between the pixel electrode PIj formed to match the shape of each color filter ■◎■ via an extension of the gate line Gi.

Therefore, in this device, green display pixels are arranged in a checkered pattern, and other red and blue display pixels are arranged alternately between them, so that the same color can be displayed horizontally, vertically, and diagonally. Display pixels are not lined up, so that so-called color arrangement noise such as color streaks does not occur.

Furthermore, since the green display pixels, which have the greatest influence on visual resolution, are arranged in a checkerboard pattern, the display resolution is greatly improved. In other words, the green resolution chart is the third one.
As shown in Figure B, it is possible to obtain horizontal and vertical resolution equivalent to the monochromatic case shown in Figure A. In this case, the human eye's sensitivity to resolution is greater in the vertical and horizontal directions than in the diagonal direction. Therefore, extremely good resolution can be obtained. Note that C is a red and blue resolution chart.

Further, by setting the aperture ratio of the green display pixel to 1/2, the overall display color balance remains unchanged.

In this way, with this device, extremely good image quality can be obtained.

FIG. 4 shows another example of the circuit pattern. In this example, the vertical signal line Lj and the gate line Gi are arranged in a straight line, and the switching elements for the red and blue pixel electrodes are connected to the adjacent green display. It is provided inside the pixel.

According to this, the area of the red and blue pixel electrodes can be expanded compared to the conventional one, and the area of the green pixel electrode can be expanded to 1/2 of that area.
By setting the area to , it is possible to provide two switching elements in the remaining portion, so that the above-described device can be realized extremely easily.

〔Effect of the invention〕

According to the present invention, green display pixels are arranged in a checkered pattern, and display pixels of other colors are arranged alternately between them, so even if a mosaic color filter is provided, diagonal color streaks will not occur. Also, by arranging the green display pixels in a checkered pattern, the vertical and horizontal resolution has been improved, making it possible to obtain extremely good image quality.

[Brief explanation of the drawing]

FIG. 1 is an example of the S factor of the present invention, FIGS. 2 to 4 are diagrams for explaining the same, and FIGS. 5 to 8 are diagrams for explaining a conventional device. L1~Lm are vertical signal lines, 01~Gn are gate lines, M
11~Mnn+ are switching elements, P11~PnI
11 is a pixel electrode, ■ is a red color filter, ■ is a green color filter, and ■ is a blue color filter.

Claims (1)

[Claims] A plurality of first signal lines arranged in parallel in the vertical direction and a plurality of second signal lines arranged in parallel in the horizontal direction are provided, and these first, In a color display device in which a pixel electrode is provided at each intersection of a second signal line via a selection element, green display pixels are arranged in a checkered pattern, and display pixels of other colors are arranged alternately between them. Then, the aperture ratio of the green display pixel is set to 1/2 of the aperture ratio of the display pixels of other colors.
A color display device characterized in that: