Panel type color display device and system for processing image information

• US 6,078,304 A
• Filed: 10/20/1995
• Issued: 06/20/2000
• Est. Priority Date: 10/24/1994
• Status: Expired due to Fees

• Current Assignee: Kazuo Aoki, Tri-Light Investment Limited, Yasuaki Gomi
• Original Assignee: Kazuo Aoki, Tri-Light Investment Limited, Yasuaki Gomi
• Inventors: Miyazawa, Kuniaki
• Primary Examiner(s): Mengistu, Amare
• Assistant Examiner(s): LEWIS, DAVID LEE
• Application Number:
  US08/546,330
• Time in Patent Office: 1,705 Days
• Field of Search: 345/88, 345/89, 345/98, 345/99, 345/100, 345/102, 345/144, 345/147, 345/148, 345/155, 345/186, 345/150
• US Class Current: 345/88
• CPC Class Codes: G09G 2310/0235 Field-sequential colour display
• CPC Class Codes: G09G 3/2018 by time modulation using two or more time intervals
• CPC Class Codes: G09G 3/3406 Control of illumination source illumination devices structurally associated with liquid crystal cells G02F1/1336
• CPC Class Codes: G09G 3/3611 Control of matrices with row and column drivers
• CPC Class Codes: G09G 3/3685 Details of drivers for data electrodes

Abstract

According to the panel type color display device of the present invention, the image information is converted into the serial data in which the color data of colors R, G, and B are sequentially switched within the video frame, and the image data for one screen are repetitively overwritten in the respective color frames of R, G, and B at the time period of the display frame, and the liquid crystal is intermiittently driven plural times. Thus, the high-speed response and the large responding quantity of the liquid crystal can be surely obtained comparing with the case of continuously driving the liquid crystal. As a result, the video with high contrast can be realized in respective short color frames, and the gradation difference can be expressed by regulating the number of repetitive overwriting.

Claims

1. A color display comprising:

a variable transmittance portion, the variable transmittance portion having a plurality of pixel elements, the variable transmittance portion having a characteristic amount of time in which it reaches a maximum level of transmittance upon application of a constant voltage;

a backlight source; and

a driving cirtuit for varying the transmittance of each pixel element of the variable transmittance portion in response to color image information, wherein the driving circuit drives each pixel element of the variable transmittance portion with a plurality of pulses, each of the plurality of pulses having a duration shorter than the characteristic duration of time in which the variable transmittance portion reaches the maximum level of transmittance upon application of a constant voltage.

2. A color display as in claim 1, wherein the backlight source emits red, green, or blue light.

3. A color display as in claim 1 comprising a plurality of backlight sources and wherein each of the plurality of backlight sources is associated with one or more of the plurality of pixel elements and wherein each of the plurality of backlight sources may be controlled independently of the others.

4. A color display as in claim 1, wherein the driving circuit drives the variable transmittance portion sequentially for each of colors red, green, and blue.

5. A color display as in claim 2, wherein the driving circuit comprises a memory for data.

6. A color display as in claim 1, wherein the variable transmittance portion comprises a super twisted nematic liquid crystal.

7. A color display as in claim 1, wherein the variable transmittance portion comprises a thin film transistor device.

9. A method of driving a color display panel as in claim 6, comprising the step of:

converting the color image information into serial data such that each of the plurality of pixel elements is driven in response to color image information sequentially for each of the colors red, green, and blue.

10. A method of driving a color display panel as in claim 7, comprising the step of:

varying the number of pulses used to drive the pixel elements in response to gradation information in the color image information, thereby displaying gradations of color.

8. A method of driving a color display, the color display comprising a variable transmittance portion, the variable transmittance portion having a plurality of pixel elements and the variable transmittance portion having a characteristic amount of time in which it reaches a maximum level of transmittance upon application of a constant voltage;

the method comprising the steps of;

receiving color display information;

driving each of the plurality of pixel elements with a plurality of pulses in response to the color display information, wherein each of the plurality of pulses has a duration shorter than the characteristic amount of time in which the variable transmittance portion reaches a maximum level of transmittance upon application of a constant voltage.