JPS63174089A - Contrast display system - 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] [Summary] The present invention is a display device using a raster scan method, in which low luminance In the display area, adjacent pixels in the area are alternately turned on and smoke-extinguished to realize low-luminance display with reduced flickering.

[Industrial application field]

This relates to a method for displaying pseudo gradation in a display device that uses bitmap pixels and uses a raster scan method and is not capable of displaying luminance gradation in units of two pixels. The present invention relates to a gradation display method in which pixels are alternately turned on and off to obtain a low-luminance display.

[Conventional technology]

Conventionally, in a display device with a single 0 display brightness, 1
When performing gradation display on a pixel basis, in addition to alternately turning on and off the pixels in the entire low-luminance area, it is also possible to turn on and off every other raster display row. However, there were devices that successively reversed this to obtain a low-brightness display.

[Problem that the invention seeks to solve]

According to the above-mentioned prior art, especially in an area where low-brightness display parts are concentrated, there is a problem in that the screen flickers because the lights are turned on and off all at once in a certain period.

[Means for solving problems]

It is equipped with a storage means for storing pattern data of a display object and brightness data of the display object, and when displaying a predetermined area with low brightness according to the storage means etc., each pixel constituting the predetermined area is Lights on.

The display state is controlled to be alternately adjacent to the non-lit state, and the display state is reversed at a predetermined period.

[Effect]

By controlling the display state to be different for each pixel and reflecting the display state at a predetermined cycle.

Pixels that turn on or off at a certain point are distributed,
Moreover, since both exist in a mixture, they have the effect of reducing visual flicker.

〔Example〕

FIG. 1 shows an embodiment of the gradation display method of the present invention.

A time chart in one embodiment is shown in FIG.

In FIG. 1, pattern memory 1-1 stores the shape of image data to be displayed, and brightness memory 1-2 represents the brightness of the area within the shape stored in pattern memory 1. . Flip-flop (FF) 10-12.
Gates 13 to 16 receive the output data of the luminance memory and a vertical synchronization signal (VSYN) which is a synchronization signal for image display;
Horizontal synchronization signal (H3YNC) and dot clock tl17 (
The display signal is generated according to the signal level (VCL).

Here, 1. For example, it is assumed that the pattern memory 1-1 stores the brightness data of the character font area and the brightness memory 1-2 stores the brightness data of the character font area of the pattern memory 1-1, and the brightness data is "1". If the output is 0'', the signal line G2 will always be 1, and the 2 display signal will be the pattern memory 1-2. It becomes equal to the output of 1.

Further, when the outputs of the pattern memory 1-1 and the brightness memory 1-2 are "1", that is, low brightness display is performed, the display signal is controlled according to the signal G1.

Signal G1 is an exclusive OR gate 13゜14
The signal Q1 is a signal that is output by calculating the exclusive OR of the signals Q1 to Q3, and the signal Q1 is inverted every time 100 pages are displayed by applying the VSYNC signal to FF10. Signal Q2 is a signal output from FFII and inverted for each display row, and signal Q3 is a signal output from FF12 and inverted for each pixel. As a result, the signal G1 is inverted every pixel display during the display period of one row, and the signal G1 in one row and the signal Gl in the next row are "0" and "1".
" is inverted. For example, when displaying pixel a2 in FIG. 2, signal G1 is "0", but for pixels a1 and a3 around 1, it becomes "1". At b2 below a2 on the screen, the G1 signal becomes 1", and at the same position and pixel a2° as a2 in the next frame, the signal G1 becomes "1" and the previous frame is displayed. It is reversed with time. An example of this display is shown in Figure 3.
1) and (2) are displayed alternately.

In this way, pattern memory 1-1 and brightness memory 1-2
By setting both of the outputs to "1", adjacent pixels are controlled to turn on and off alternately, and the display state of each pixel changes alternately for each display of one frame. A pixel that repeatedly turns on and off appears darker than a pixel that is always on, making it possible to display two levels of gradation.

FIG. 4 shows an example of the operation of one embodiment. Here, Figure 4 (1)
are all 1'' with the data of pattern memory 1-1, and the fourth
If Figure (2) is the data in the brightness memory 1-2, in this case, the displays shown in Figure 4 (3) and (4) are alternately performed, and as a result, the display as shown in Figure 4 (5) is low. It becomes possible to recognize that the display is displayed at brightness and normal brightness.

〔Effect of the invention〕

As explained in detail above, according to the present invention, when displaying at low luminance in a device that displays at a single luminance, bright spots and dark spots are arranged so that they are evenly mixed and are alternately arranged. This has the effect of reducing visual phenomena such as flickering and single color unevenness.

In addition, in the above examples, a display screen that lights up and has luminance is explained, but the invention is not limited to this, and a display screen that changes the color density by changing the amount of passing or reflected light using a liquid crystal or the like is also applicable. The same applies to devices that have.

[Brief explanation of the drawing]

FIG. 1 shows an embodiment of the gradation display method of the present invention. FIG. 2 is a time chart in one embodiment.
Display example. FIG. 4 is an example of operation in one embodiment. In the drawing. 1-1 is a pattern memory. 1-2 is a brightness memory. 10.11.12 is a flip-flop (FF). 13, 14, 15, and 16 indicate gates, respectively. Figure 1

Claims (4)

[Claims] (1) In a raster scan type display device,
A storage means (1) is provided for storing data of a display object and brightness data of the display object, and low brightness display of a predetermined area according to the storage means (1) is carried out by each adjacent pixel of a plurality of pixels constituting the predetermined area. A gradation display method characterized by controlling each pixel to have a different display state, and inverting the display state at a predetermined period. (2) The storage means (1) includes a pattern memory (1-1) for storing shape data of the displayed object, and a brightness memory (1-1) for storing the brightness data of the displayed object.
2) The gradation display method according to claim 1, which comprises: (3) The gradation display system according to claim 1, wherein the different display states are a bright display state and a dark display state of the pixel. (4) The gradation display method according to claim 1, wherein the inversion of the display state occurs every time one field of raster scanning of the display screen of the display device is completed.