JPS59135427A - Liquid crystal panel used for color image display device - Google Patents

Abstract

PURPOSE:To perform full-color displaying without deviation in the color display by providing opposite electrodes so as to intersect at an angle of 60 deg. to the one electrode and constituting the picture elements formed by the adjacent three intersected positions in such a way as to display light of red, green and blue. CONSTITUTION:Electrodes 6, 7 are provided at an equal interval in such a way as to intersect with each other at an angle of 60 deg. on the inside surfaces of upper and lower substrates facing each other with a liquid crystal 5 in-between. The adjacent three intersected positions of both electrodes 6, 7 form a display unit part consisting of the three picture elements disposed in a regular triangle shape. A color filter 10 arranged with filter elements 11-13 of red, green and blue in accordance with the three picture elements is disposed. Thus a liquid crystal panel 1 forms the liquid crystal panel of a dot matrix system consisting of the regular arrangement of the display unit parts emitting light to R, G, B and the full color display free from deviation is accomplished.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an image display device capable of performing full color display using a liquid crystal, and in particular, an image display device in which the electrodes facing each other with the liquid crystal in between are each a plurality of parallel electrode groups, and This invention relates to a so-called dot matrix type liquid crystal panel electrode structure configured to intersect with each other.

Systems for displaying images include light emitting diode systems and plasma display systems.

There are cathode ray tube systems, liquid crystal display systems, etc., but liquid crystal display systems are advantageous because they have a low operating voltage and can be made into a flat shape, and various driving methods and liquid crystal board wiring layouts have been proposed and realized. There is.

Thus, as a device for displaying a complex image or multiple types of images on the same plane, the electrodes that sandwich the liquid crystal and face each other are formed into, for example, a plurality of rectangular electrode groups, and the electrodes that sandwich the liquid crystal are arranged in an orthogonal shape. An image display device using a so-called dot matrix method is disclosed in U.S. Patent No. 3.410.999.
No. 3,982.239, etc., and to explain it in FIGS. 1 to 4-C, a liquid crystal panel 1 constituting a display section of an image display device has an upper substrate 2 such as a glass plate, etc. A lower substrate 3 such as a glass plate facing the second substrate 2 is sealed with a seal portion 4 to form a space, and an Np-PPM liquid crystal 5 is sealed in the space. A liquid crystal 5 is provided on the upper substrate 2 and the lower substrate 3.
Rectangular electrodes 6 and 7 are formed to be orthogonal to each other with the two substrates 2 in between, forming a grid-like electrode pattern as a whole, and terminal electrodes 6a protruding from the lower substrate 3 are provided at the ends of the two substrates 2. A terminal electrode 7a protruding from one substrate 2 is provided at the end of the lower handle plate 3. On both end plates 2 and 3,
Both end plates 2.31+j+ rotate the axial direction of the molecules of the liquid crystal 5 by 90 degrees, and orientation processing is performed so that the direction of the h+E axis is perpendicular to both end plates 2 and 3, resulting in a Rice I arrangement.
Linear polarizing plates 8 and 9 are provided on the outside of both end plates 2.degree. 3, respectively.

In such a configuration, the voltage +·k[j
, 7, where no voltage higher than the threshold voltage is applied, the liquid crystal 5 maintains its initial molecular alignment and is in a twisted alignment (see the left side of FIG. 4). Further, when a voltage higher than the threshold voltage is applied, the electrode 6 to which the voltage is applied,
Only the molecules of the liquid crystal 5 located between the two ends of the liquid crystal 5 rotate in a direction parallel to the electric field, changing to a pomeotropic arrangement in which the direction of the director is perpendicular to both end plates 2.3 (see the right side of FIG. 4). Therefore, the polarizing plates 8 and 9 provided on the outside of both end plates 2.3 are misaligned so that the polarization axes are parallel to each other at the electrodes 6 and 7 where a voltage higher than the threshold voltage is applied (the 4th Light can pass through the liquid crystal panel 1 only on the right side of the figure, but cannot pass through other parts (on the left side of Figure 4), and only the electrodes 6 and 7 to which a voltage equal to or higher than the threshold voltage is applied are bright, resulting in a negative display. . Furthermore, if the polarizing plates 8 and 9 are arranged so that the polarization axes are perpendicular to each other, the electrodes 6 and 7 can be applied with a voltage equal to or higher than the threshold voltage.
Light cannot pass through the liquid crystal panel 1 only in the area (right side in Figure 4), but can pass in other areas (left side in Figure 4), and the voltage is below the threshold voltage.
Only the electrodes 6 and 7 to which the second voltage is applied are displayed as dark.

By the way, a display device which uses this liquid crystal panel 1 to constitute a -ζ flat plate type color image display device and can perform full color display is described in Japanese Patent Publication No. 54-18.886. The outline is explained in Figures 5 to 7.
The liquid crystal panel 1 is rectangular, for example, 30.48 cm (
1 foot) x 30.48 (1 foot) A grid-like electrode pattern is formed as a whole. The locations where both electrodes 2 and 3 intersect serve as pixels, and there are 750,000 pixels. Further, the polarizing plate 8 is horizontal and its polarization axis is oriented in a direction parallel to the plane of the paper, and as a result, light polarized in the horizontal direction passes through the polarizing plate 8, but light polarized at right angles to the horizontal direction is polarized. It does not pass through plate 8. The polarizing plate 9 is oriented such that its polarization axis is the same as that of the polarizing plate 8. In addition, the liquid crystal 5 has both end plates 2,
3. The inner surface has been subjected to orientation treatment.

Reference numeral 10 denotes a color filter provided behind the rear polarizing plate 9, in which a mosaic array consisting of red, green, and blue rectangular filter elements 11, 12, and 13 in contact with each other has a black edge 1.
Three sets of squares separated by 4, that is, three horizontally adjacent filter elements 11, 12 and 13 form a square, and the row of filter elements 11 connected in the vertical direction is red, and the row of filter elements 12 is green. <, It and filter element 13
The columns form three sets of skeletons and are precisely aligned with the intersecting pixels of both electrodes 6.7.

In such a configuration, by selectively applying a voltage to both electrodes 6.7, light passes only through pixels to which a voltage higher than the threshold voltage is applied, thereby changing the color of the color filter 10 located behind it. The pixels adjacent to each other corresponding to the filter elements 11, 12 and 3 of the color filter 10 form one unit display section, and the deviation varies depending on the combination of colors visible from this unit display section. For example, in the unit display unit shown in FIG. 6, the filter element 11 of the color filter 10
．． If the voltage is applied so that only the light passes through the pixels R and G facing the filter element 12, the entire unit display section will appear yellow, and similarly, if only the light passes through the pixels R and B facing the filter element 11. If only light passes through pixels G and B, they will be displayed in blue and green, respectively. Furthermore, by applying a voltage smaller than the value voltage, the direction of the director of the molecules of the liquid crystal 5 can be completely changed to both substrates 2 and 3. If it is not perpendicular to , it is possible to limit the amount of light passing through, and therefore it is possible to make a difference in the brightness ratio of each pixel, R, G, and B, and it is possible to display other colors.

Of course, when displaying all of the pixels R, G, and B, the standalone display section displays white.

Therefore, it is possible to realize a color image display device by setting up a display of 250,000 units consisting of 750,000 pixels and scanning the image using an X-Y matrix method. It can be used as a new color television display device to replace tubes.

By the way, in this type of liquid crystal panel 1, the red pixel R2, the green pixel G, and the blue pixel B are arranged as shown in FIG. Pixels of the same color are in contact with each other in the direction of (lI#), resulting in uneven color display.Also, it is also possible to arrange pixels of the same color diagonally as shown in Figure 8. The unbalanced color display still remains unresolved.

This invention was made in view of these conventional problems, and the opposing electrodes of a dot matrix liquid crystal panel are arranged parallel to each other with the liquid crystal in between, and one electrode is oriented at an angle of 60 degrees to the other electrode. The two electrodes are arranged so that they intersect at an angle of 120 degrees), and the pixels that come to the intersection of both electrodes form an equilateral triangle when the centers of three adjacent pixels are connected.
These three pixels are arranged side by side and constitute one unit display section, and each of the three pixels forming one unit display section is configured to display light of a different color of red, green, and blue, It is an object of the present invention to provide an image display device that can perform preferable full color display with less bias in color display.

Hereinafter, this invention will be explained based on the embodiments shown in FIGS. 9 to 11.
In particular, since the general structure is the same as that of the liquid crystal panel 1 shown in Section 5, the electrodes 6.7 and color filter 10, which is the point I of this invention, will be explained below. We will focus on explaining the following.

The electrodes 6 and 7 each consist of a plurality of rectangular electrodes with the same width or formed in parallel with equal gap intervals, and as shown in FIG. ) The column electrodes 7 extending in the vertical direction of the paper are inclined upward to the right, and are at an angle of 60 degrees (120 degrees) with respect to the row electrodes 6 extending in the horizontal direction of the paper. Intersect, L-), is provided. Then, the pixels formed at the intersection of both electrodes 6 and 7 are arranged side by side so that when the centers of three adjacent pixels are connected, they form an equilateral triangle and one unit representation r;1- is formed. It is.

The color filter 10 also includes three sets of red, green, and blue diamond-shaped filter elements 11, 12, and a mosaic array having substantially the same shape as the pixel shape and separated by a black edge 14, which are adjacent to each other. , the rows of filter elements 11 connected in the right direction of the page form three sets of red, the rows of filter elements 12 form a chain, and the rows of filter elements 13 form three sets of skeletons, and one jp position display section. Filter element 1 is applied to the three pixels of
The filter elements 11.12 and 13 are precisely aligned with the pixels so that one pair of filter elements 11.12 and 13 are arranged opposite each other; This can be realized by forming a straight line connecting the centers to intersect the one electrode 6 at an angle of 30 degrees (150 degrees).

Therefore, "= ---: One unit display section has three pixels R, G and ■ that display each color of red, green and blue.
3, and each pixel R, G and I3 has a number j1,
The distance between the two centers is 2(a+b)/', fr, and is uniform, where a is the width of one of the electrodes 6 and 7, and b is the cap interval between the electrodes.

Therefore, by selecting the passage of light through each pixel R, G, and I3, the unit display section can display light of many different colors as described in the conventional example. Moreover, the distances between the centers of any two of the three pixels R, G, and B constituting one unit display section (as they are equal, the color display does not shift as in the conventional case).

Note that instead of providing the filter elements 11, 12, and 13 for displaying red, green, and blue in the pixels R, G, and B in the color filter 10, the filter elements 11, 12, and 13 for displaying red, green, and blue in the pixels R, G, and B are provided in the second pixel R of at least one of the electrodes 6 and 7. , G, and B shapes, similar effects can be obtained by directly providing a colored layer.

Furthermore, the same operation as described above can be obtained by using a guest-host type liquid crystal panel 1 in which a dichroic dye is placed in the Np-FEM liquid crystal 5 and the polarizing plate 9 is not used.

In addition, this liquid crystal panel 1 can be of a passive type if the light source is placed at the rear, or a reflective type if the illumination light is emitted from the front and a reflector is provided at the rear, or a reflective type if the light source is placed at the rear. A transflective type can be achieved by providing a transflective plate such as a half mirror at the rear.

Furthermore, as another embodiment of the liquid crystal panel 1, the shape of the electrode 6.7 may be changed from a rhombus to a circle by making the intersection of both electrodes 6.7 circular, as shown in FIG. According to this, since the gear spacing between each pixel is made uniform, it is possible to obtain a display section with even less color deviation.

As described above, according to the present invention, the opposing electrodes of a dot matrix type liquid crystal panel are each formed by a plurality of parallel electrodes, and each electrode is parallel to the other electrode with the liquid crystal in between. The other electrode is arranged to intersect at an angle of 60 degrees (120 degrees), and the pixel formed at the intersection of both electrodes is
Three adjacent pixels are arranged side by side so as to form an equilateral triangle when their centers are connected, and these three pixels are used as one unit display section, and each of the three pixels forming one unit display section is red, It is configured to display light in different colors of green and blue, and can display different colors with the same pattern, making it possible to realize a liquid crystal panel that can display any color.It can be used for a variety of purposes. There are color image display devices such as television display devices that replace display boards and fluoroun tubes.

Furthermore, since the pixels that display each of the three primary colors of light are appropriately dispersed, there is less color deviation compared to conventional display devices of this type, and furthermore, because it uses a twisted type liquid crystal, the power consumption is low. An attractive color image display device with extremely good contrast can be realized.

[Brief explanation of the drawing]

1 is a plan view of a conventional liquid crystal panel, FIG. 2 is an enlarged cross-sectional view taken from section line H-11 in FIG. 1, and FIG. 3 is an enlarged sectional view taken from section line Ill-- in FIG. FIG. 4 is a schematic diagram of the liquid crystal panel shown in FIG. 6 is an enlarged plan view of the main parts of the unit display section of the liquid crystal panel shown in FIG. 5, and FIGS. 7 and 8 are plan views illustrating the state of color display of the liquid crystal panel shown in FIG. , #≠# right figure, FIG. 10 is a plan view illustrating the electrode shape of the liquid crystal panel shown in FIG. 9, and FIG. 11 is a plan view illustrating the state of color display of the liquid crystal panel shown in FIG. 9. FIG. 12 is a plan view illustrating the shape of electrodes used in another embodiment of the liquid crystal panel of the present invention. 1: Liquid crystal panel 2: Upper substrate 3: Lower substrate 5; Liquid crystal 6.7: Electrode 8, 9: Polarizing plate 10: Color filter 11,] 2.13: Filter element Fig. 1 g Fig. 9 Fig. 4 Figure 5 Figure 6 Figure 7 Figure 8 1111:]) [I GREEN [BLUE 9th]
Figure 4 Figure 1O

Claims (1)

[Scope of Claims] A liquid crystal having a property in which electrodes each consisting of a plurality of parallel electrodes are formed on each opposing surface of an upper and lower substrate, and the polarization plane of transmitted light is rotated in response to an electric field applied between the opposing electrodes. In a dot matrix liquid crystal panel, the electrodes provided on the upper and lower substrates are parallel to each other with the liquid crystal in between, and the other electrode is at an angle of 60 degrees (12 degrees) with respect to one electrode.
The three pixels are arranged so that they intersect at an angle of 0 degree), and the pixels formed at the intersection of the two electrodes form an equilateral triangle when the centers of three adjacent pixels are connected, and the three pixels is one unit display section, and a color filter or a colored layer is provided so that the three pixels constituting the one unit display section each display light of different colors of red, green, and blue. Liquid crystal panels used in image display devices.