JPS6397921A - Liquid crystal display device - Google Patents

Abstract

PURPOSE:To permit gradation display by an integrated circuit of binary display by weighting plural display signals, then converting the signals to the flickering frequencies of the display and converting the phases of the periods of the flickering so as to shift the same by the positions of the display. CONSTITUTION:This device is provided with a conversion circuit 1 which is inputted with the plural display signals and converts the signals to the flickering signals for gradation display, the integrated circuit 4 for binary driving of a liquid crystal panel 3, and an integrated circuit which converts video signals to the signals necessary for the liquid crystal display device. One period of the flickering is obtd. by drawing 8 image screens and the flickering frequencies corresponding to the respective gradations are the same but the phases are shifted by the positions stipulated by even and odd lines and rows. The reason thereof lies in that the flickerings go into sight in the case of flickering with the same phases when the parts of the same gradations are adjacently displayed. Patterns are so selected that the ratios of the lighting indicated by the even and odd lines between the respective frames are uniformized. The gradation display is thus obtd. by the liquid crystal display device of the binary display.

Description

[Detailed description of the invention] [Industrial application field] TECHNICAL FIELD The present invention relates to dermatology display in a liquid crystal display device.

[Conventional technology]

As shown in Figure 8, as a method of displaying gradations in a conventional liquid crystal display device, an on-voltage is applied to the common electrode of the liquid crystal display panel (while a selective pressure is applied at No. N), an on-voltage is applied to the signal electrode. By changing the amount of time that the off-voltage is applied, the effect and directivity were changed and the gradation was achieved.

[The problem that the invention is trying to solve]

However, the conventional gradation display method has the drawback that the pulse width of the waveform added to the signal electric current needs to be changed depending on the gradation, which makes the integrated circuit for driving it complicated.

Another disadvantage is that as the display capacity of the liquid crystal display device increases and the duty of dynamic driving increases, the ratio of the on-voltage to off-voltage of the signal waveform and the degree of gradation do not match.

SUMMARY OF THE INVENTION The present invention solves these problems by providing a gradation display that is unique to a double-chain display integrated circuit without using a 9th integrated circuit for gradation display. be.

[Means for solving problems]

The liquid crystal display device of the present invention weights a plurality of display signals and changes the frequency of blinking of one display in a dot matrix liquid crystal display device that performs gradation display to obtain a gray scale, and the blinking of the display Shifting the phase of the period according to the position of the display on the liquid crystal display device, converting the plurality of display signals into a blinking frequency of the display after weighting them, and converting the phase of the blinking period? It is characterized in that the conversion is performed so as to be shifted depending on the position of the display.

〔Example〕

FIG. 1 is a configuration diagram of an embodiment of the present invention, in which 1 is a conversion circuit that inputs a plurality of display signals and converts it into a blinking signal for gradation display, and 2 is a conventional liquid crystal display that performs two-direction display. In a display device, a liquid crystal panel 3't2 (an integrated circuit for surface driving (hereinafter referred to as a driving IC) 4 and a signal generally input to a CRT (hereinafter referred to as a video signal) consisting of horizontal and vertical periodic signals and two-time display signals (hereinafter referred to as a video signal) t-liquid crystal. An integrated circuit (
Below is Controller E C) From 5, Controller E C
5 is Seiko Epson stock ■5ED1340 or ■E
Products such as 111CD1341 are known.

The liquid crystal display device 2 configured in this manner can perform two-direction display using two-direction video signals.

In this embodiment, there are three display signal lines that provide gray scales, and the number of gray scales will be described below as eight to the third power of 2.

As for how to give gradation, the period of one blink shown in FIG. 2 is 8 screens and one period. (One frame of tg1 screen below,
The second screen is called 27 frames. ) Steps 0 to 3 indicate the status of the display signal, and lighting and non-lighting in each frame are displayed in the squares. and odd columns, right and odd rows and even columns.

The lower right shows the lighting and non-lighting states 9 of dots located at the intersections of odd rows and odd columns (hereinafter referred to as an even-odd matrix).

As shown here, the frequency of blinking corresponding to each gradation is the same, but the phase is shifted depending on the position defined by the even and odd rows and columns. This is because when parts of the same gradation are displayed adjacent to each other, if they blink at the same phase, flickering will be visible.

To prevent flickering, one lighting and one non-lighting should be dispersed as much as possible. If the tally is (Work 0. Work 1. Work 5) = (0, 1
, 1), the blinking pattern is 1.1,1°1.0,0,0
．． Instead of 0, it is 1,0°1.0,1,0,1, as shown in Figure 2.
It is 0. However, 1 indicates lighting and 0 indicates non-lighting.

Further, in each gradation, the pattern is selected so that the ratio of lighting indicated by an even-odd matrix between each frame is uniform.

If we put
* 0), the even-odd matrix from frames 1 to 8 is expressed as below, and the lighting ratio in each frame is 4/4.4/4.
．． 2/4.4/4.4/4.4/4.2/4, 4/4
roar 7 ram 3. It changes greatly in frame 7, and if the same gradation parts are displayed next to each other, it will flicker easily, so if we do it as shown in Figure 2, the lighting ratio in each frame will be 4/4.3/4.
．． 4/4.3/4.4/4.3/4.4/4.3/4, so there is almost no change between each of the 7 frames, and flickering can be prevented.

This flashing signal? It is the conversion circuit l that gives the third
The configuration diagram is shown in the figure.

8 is a phase comparison circuit, 9 is a voltage controlled oscillation circuit, i.

is a frequency dividing circuit. These three circuits provide a clock with a frequency corresponding to each dot of the display signal. By moving the inverting flip 70 knob 11i using this clock, even columns and odd columns can be set. This is used as a column signal. shall be.

Further, by moving the inverted 7r lip 7r:1 knob 12 using the horizontal synchronizing signal, even and odd rows can be set.H is used as a low signal.

Also, by moving the 3-bit counter 13 with the vertical synchronization signal, frames 1 to 8 are set as a settable frame signal.

Logical operations are performed by inputting these column signals, row signals, frame signals, and display signal circuits ◎ to 3 to the logic circuit section assembled in the logic circuit shown in Figure 4.
Output matching Figure 2 can be obtained.

FIG. 5 shows another implementation column of the present invention, in which the logic circuit section 6 of the implementation column shown in FIG.
The contents of ROM 7 are shown in FIG. 6.

This allows one ROM to be used without using multiple logic circuits.
7 can be substituted.

FIG. 7 is another embodiment of the present invention, and is a block diagram for converting display signals of three colors red, green, and blue into gradations of a color display personal computer No. 14, in which red is converted to gradation. 2. Green. Gradation display is performed by weighting W with 1.

In another embodiment of the present invention, the conversion circuit l is installed in front of the video input of an ordinary black-and-white CRT, or the input of a KL or plasma display that can display signals from a CRT, thereby achieving the sky arrangement shown in FIG. It is possible to convert the color display to gradation and display it in the near future.

〔Effect of the invention〕

As described above, according to the present invention, an N F-J display can be obtained using a two-direction liquid crystal display device, and the gradation thereof is as follows.
Since it is determined based on the blinking frequency, the effect of making the % gradation brighter can be obtained.

Furthermore, since the display signal is converted into a blinking dot signal in real time, just by changing the conversion circuit 1, it can be used not only for liquid crystal displays but also for ML, plasma displays, and CR displays.
Gradation display of devices such as T can be easily performed. The effect is ti.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an embodiment of the present invention. FIG. 2 is a diagram of the blinking pattern of the present invention. FIG. 3 is a circuit diagram of a specific circuit array of the logic circuit unit 6 of the conversion circuit 1 of the implementation array. FIG. 4 is a diagram of an example circuit of the switching circuit of the implementation array. ! FIG. 5 is a diagram of the circuit array of the logic circuit section of the conversion circuit 1 using the high-speed read ROM 7. FIG. 6 is a table diagram of the data contents of the high-speed read ROM 7. FIG. 7 is a diagram of another embodiment of the present invention. 1: Conversion circuit 2: Liquid crystal display 3: Liquid crystal panel 4: Drive C 5: Controller C 6: Logic circuit 7: ROM 8: Phase comparator circuit 9: Voltage controlled oscillation circuit 10 : Frequency divider circuit 11: Inversion flip 70 tube 12: Inversion flip-flop 13: 3 bit binary counter 14; Color display personal computer, etc. 15: Common electrode signal t6: Signal electrode signal in case of 4/8 gradation 17: Signal If the electrode signal is 6/81V, the applicant is Seiko Epson Corporation, Figure 3, Figure 6, Figure 7.

Claims (3)

[Claims] (1) In a dot matrix liquid crystal display device that performs gradation display by weighting multiple display signals, it is possible to obtain gradations by changing the frequency of blinking of the display, and to change the cycle of the blinking of the display. Shifting the phase depending on the position of the display on the liquid crystal display device, converting the plurality of display signals into a blinking frequency of the display after weighting them, and shifting the phase of the blinking cycle depending on the position of the display. A liquid crystal display device characterized in that it can be converted into a liquid crystal display device. (2) In the liquid crystal display device according to claim 1, the blinking of the display is characterized in that the lighting time is dispersed and uniform in the cycle of the blinking of the display. A liquid crystal display device. (3) In the liquid crystal display device according to claim 1, the phase of the blinking cycle of the display is such that the position at which the display is displayed on the liquid crystal display device is an intersection of an odd row and an odd column; A liquid crystal display device characterized in that the display is shifted according to four cases: the intersection of odd rows and even columns, the intersection of even rows and odd columns, and the intersection of even rows and even columns.