JPS59139078A - Ic board for active panel - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides an active system having an active interface that can control the signals applied to the pixel electrodes and selectively configure the image by decoding the signals input to the pixels. It concerns matrix panels.

In recent years, expectations for display materials have been increasing, and in particular, the controversy over display materials has become one of the reasons why the added value of the entire product is blurred.

In addition, it provides freedom of display contents, increases display capacity, plays a role in helping to improve the performance of the final product, enables many functions to be added, and also improves display quality and has an excellent design. It also serves as a starting point for creating new products.

Many studies are currently being conducted with the aim of improving the performance of display devices.

Don't Matrix panels are ideally suited for liberalizing display and increasing capacity. However, if an attempt is made to realize a display system using a dot matrix r-based multiplex drive, there is an inherent limit to its display capacity, and custom-made modifications to the liquid crystal or a multiplex matrix system are being considered. 1 is still not satisfactory.

On the other hand, the memory type active matrix panel (corresponding to Japanese Patent Application No. 1757/17592) does not have the above-mentioned inherent limitations and can be said to be the most suitable system for dot matrix panels.

Figure 1 shows an example of the pixel circuit of a memory-type active panel. Indicated. 1 is one pixel, and this is constituted by a memory circuit 2 that stores the display contents of the pixel, and a control circuit wr3 that uses this information to control a signal that is applied to the pixel current. The pixel selection signal 5 is written into the data 4 of the display content of the pixel in a launch circuit constituted by a clocked inverter 6.7 and an inverter 8, and is held there.

A low frequency signal 9 (hereinafter referred to as 00MM0N signal) for driving the liquid crystal is controlled to open and close two clocked inverters 12 and 13'i by a signal 10 and 11 from this latch circuit, and is applied to the pixel electrode 14. be done. The 'rC transparent electrode formed on the top glass of the panel has the same 00M as 9.
A M0N signal 15 is applied. Clocked inverter 12 is turned on by signals 10 and 11 from the launch circuit cams.
When 16 is in the OFF state, 14 with the polarization of 00MM0N reversed is applied to the pixel electrode 14, and a voltage is effectively applied to the liquid crystal. Conversely, when the clocked inverter 13 is in the ON state and the clocked inverter 12 is in the OFF state, the OOM ON signal is applied to the pixel electrode 14, and no voltage is effectively applied to the liquid crystal. The two difference tones are used and displayed on the LCD.

However, it has features such as low voltage drive, low current consumption, high pixel density and excellent display quality.
There are a large number of elements, eight in each pixel, and there are disadvantages such as the number of elements in the entire screen being large, making it difficult to increase the yield.

When actually used in this self-memory activa- tion matrix panel, only a few images of a few stocks are often displayed in a certain part of the screen. For example, in a clock display, in a portion where seven AM and PM displays are displayed, only two images, PM and AM, are displayed.

With such specifications, it is impossible to construct the entire screen from pixels with no functions as shown in FIG. This portion where only a small number of images are displayed can be directly controlled by external signals such as s〃λ, and the circuit can be simplified. The purpose of the present invention is to replace the portion where only several types of percentage constant patterns are displayed with more simplified pixels, and to reduce the number of elements.

FIG. 2 shows a pixel circuit according to the invention. There is one pixel in 16, which is composed of a decoding circuit 1z that decodes the signal t, and a control circuit 18 that controls the signal applied to the pixel electrode based on the decoded signal Vr-. In this example we have two signals 19.20(K,
j), we have listed the case where four screens are selected. Two signals K, which are decoded by the LH decoding circuit, control the signals applied to the pixel' electrodes by opening and closing two clocked inverters 22, 23. 24 is a low-frequency drive signal (OOMMON signal) for driving the liquid crystal, which is controlled in the same way as the signal port circuit and applied to the pixel electrode 25. 26 is formed on the upper glass of the panel, and 'fc' is transparent. The number to be stamped is O0MM0N.

Now, 6′? As shown in Table 1, depending on L, two selection signals, A, B, 0 . Four pixels of D are selectable. Since each pixel displays either white or black on these four screens, there are 16 types of pixels P1 to P16 listed in Table 2 that change corresponding to these four screens. 6" here indicates 2, OH white, and 1rc black.

For example, the pixel indicated by P6 is white when A and 0, that is, when K is O (can be either 'LH0 or 1), and is white when K is 1 (can be either Lrl0 or 1). The decoding circuit W&17 in FIG. 2 is configured so that the color becomes black.

In this example, it can be applied to parts that do not change (with four or fewer images). FIG. 5 shows an example of a portion composed of nine pixels. The four screens are [1), +21, +3), [4]
These 'i5A, B, O,
Let it be D. For example, pixels 27, A, and B in Figure (1).

Since it is always black on the four screens of 0 and D, PI3 in Table 2
A decoding circuit corresponding to 28 is formed, and the pixels H1A and B indicated by 28 are white, 0 . , D are black, so by forming the decoding circuit in the whistle pixel corresponding to P4 in Table 2, it is possible to display two lines.

Each of the pixels P1 to P16 described above is configured with a different number of semiconductor elements. For example, is Pl a signal to the control circuit? It can be done by fixing the trace source, but P2 and @ are one AND gate (or N A
(ND gate) is required, and a more complicated circuit than rL is required for Pl etc.

Therefore, depending on the type of image, it may be impossible to significantly reduce the number of elements compared to the circuit shown in Figure 1, but in many cases, the screen circuits shown in Table 1, B, c, D2 By making a good selection, the number of elements can be reduced.

As described above, the circuit can be simplified by forming the pixel according to the invention in a portion of the screen that does not change much.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram of a pixel in a storage type attritive matrix panel. FIG. 2 is a circuit diagram of a pixel having a configuration according to the invention. FIG. 6 shows a partial screen of an example of application of the present invention. That's all for -1Ci...1 Figure 2C Figure 3

Claims (1)

[Claims] A drive signal applied to the liquid crystal by a circuit made up of semiconductor elements formed on a silicon substrate,
In the active matrix panel to be displayed, there is a decoding circuit that decodes the signal from the external circuit, and a control circuit that controls the signal printed on the pixel electrode by the decoded signal of the circuit. An integrated circuit board for an active panel, comprising: