Circuit for controlling color sequential liquid crystal display and method for controlling the same

• US 8,295,627 B2
• Filed: 10/20/2008
• Issued: 10/23/2012
• Est. Priority Date: 08/13/2008
• Status: Active Grant

• Current Assignee: Sitronix Technology Corporation
• Original Assignee: Sitronix Technology Corporation
• Inventors: Lin, Chih-Yu, Chang, Chao-Chu
• Primary Examiner(s): Repko, Jason M
• Assistant Examiner(s): Nakhjavan, Shervin
• Application Number:
  US12/254,103
• Publication Number:
  US 20100039450A1
• Time in Patent Office: 1,464 Days
• Field of Search: 382/162, 382/254, 348/751, 348/761, 348/791, 349/8, 349/78, 349/80, 349/108, 345/38, 345/50, 345/51, 345/87, 345/88
• US Class Current: 382/254
• CPC Class Codes: G09G 2310/0235 Field-sequential colour display
• CPC Class Codes: G09G 3/3413 Details of control of colour illumination sources
• CPC Class Codes: G09G 3/3622 using a passive matrix G09G3/3674 - G09G3/3696 take precedence

Abstract

The present invention provides a circuit for controlling a color sequential liquid crystal display (LCD) and a method for controlling the same. The control circuit comprises a light-source driving circuit, a data driving circuit, and a scan driving circuit. The light-source driving circuit produces a driving signal for controlling the color sequential LCD to produce backlight with different colors. The data driving circuit produces a data signal and includes a plurality of data pulses. The scan driving signal produces a scan signal and includes a plurality of scan pulses corresponding to the plurality of data pulses, respectively. By controlling the pluralities of data pulses and scan pulses and the backlight, the color sequential LCD will display an image. The voltage levels of the pluralities of data pulses and scan pulses change according to different images. Thereby, power consumed by the control circuit can be reduced. In addition, color-mixing problems will be reduced according to the present invention.

Claims

1. A circuit for controlling a color sequential liquid crystal display (LCD), comprising:

a light-source driving circuit, producing a driving signal and transmitting to the color sequential LCD for controlling the color sequential LCD to produce backlights with different colors;

a data driving circuit, producing a data signal and transmitting to the color sequential LCD, and the data signal including a plurality of data pulses; and

a scan driving circuit, producing a scan signal and transmitting to the color sequential LCD, and the scan signal including a plurality of scan pulses corresponding to the plurality of data pulses, respectively;

wherein the color sequential LCD displays an image according to the voltage amplitude differences between the pluralities of scan pulses and data pulses and according to the backlights, and the voltage amplitudes of the pluralities of data pulses and scan pulses are changed according to different images.

2. The circuit of claim 1, wherein the voltage amplitudes of the plurality of scan pulses are changed according to the colors of the image.

3. The circuit of claim 1, and further comprising a timing control circuit, producing a timing signal and transmitting to the light-source driving circuit, the data driving circuit, and the scan driving circuit for producing the driving signal, the data signal, and the scan signal, respectively, according to the timing signal.

4. The circuit of claim 3, where the timing control circuit, the data driving circuit, and the scan driving circuit can be integrated into a control chip.

5. The circuit of claim 4, wherein the control chip further integrates the light-source driving circuit.

6. The circuit of claim 1, wherein the backlights controlled by the driving signal of the color sequential LCD include a red backlight, a green backlight, and a blue backlight.

7. The circuit of claim 6, wherein the backlights further include a white backlight.

8. The circuit of claim 7, wherein the white backlight is produced after the red backlight, the green light, and the blue backlight, respectively.

9. The circuit of claim 1, wherein the color sequential LCD further comprises:

a backlight module, producing backlights with different colors according to the driving signal; and

a display module, displaying the image according to the data signal, the scan signal, and the backlights.

10. The circuit of claim 1, wherein the circuit for controlling the color sequential LCD is applied to a twisted nematic (TN) LCD or a super twisted nematic (STN) LCD.

11. A method for controlling a color sequential liquid crystal display (LCD), comprising the steps of:

producing a driving signal and transmitting to the color sequential LCD, for controlling the color sequential LCD to produce backlights with different colors;

producing a data signal and transmitting to the color sequential LCD, the data signal including a plurality of data pulses; and

producing a scan signal and transmitting to the color sequential LCD, the scan signal including a plurality of scan pulses corresponding to the plurality of data pulses, respectively;

wherein the color sequential LCD displays an image according to the voltage amplitude differences between the pluralities of scan pulses and data pulses and according to the backlights, and the voltage amplitudes of the pluralities of data pulses and scan pulses are changed according to different images.

12. The method of claim 11, wherein the voltage amplitudes of the plurality of scan pulses are changed according to the colors of the image.

13. The method of claim 11, and further comprising producing a timing signal, for producing the driving signal, the data signal, and the scan signal, respectively, according to the timing signal.

14. The method of claim 11, wherein the backlights controlled by the driving signal of the color sequential LCD include a red backlight, a green backlight, and a blue backlight.

15. The method of claim 14, wherein the backlights further include a white backlight.

16. The method of claim 15, wherein the white backlight is produced after the red backlight, the green light, and the blue backlight, respectively.

17. The method of claim 11, wherein the driving signal is transmitted to a backlight module of the color sequential LCD for producing backlights with different colors according to the driving signal, and the data signal and the scan signal are transmitted to a display module of the color sequential LCD for displaying the image according to the data signal, the scan signal, and the backlights.

18. The method of claim 11, wherein the method for controlling the color sequential LCD is applied to a twisted nematic (TN) LCD or a super twisted nematic (STN) LCD.