Automatic liquid crystal display contrast adjustment

• US 20070085815A1
• Filed: 10/14/2005
• Published: 04/19/2007
• Est. Priority Date: 10/14/2005
• Status: Abandoned Application

• Current Assignee: General Motors LLC (General Motors Company)
• Original Assignee: General Motors Corporation (General Motors Company)
• Inventors: Wang, Mingheng, Oesterling, Christopher, Przybyleski, Matthew
• Application Number:
  US11/251,379
• Publication Number:
  US 20070085815A1
• Time in Patent Office: Days
• US Class Current: 345/102
• CPC Class Codes: G09G 2320/041 Temperature compensation
• CPC Class Codes: G09G 2320/066 for control of contrast
• CPC Class Codes: G09G 2330/021 Power management, e.g. power saving
• CPC Class Codes: G09G 3/2011 by amplitude modulation
• CPC Class Codes: G09G 3/3413 Details of control of colour illumination sources
• CPC Class Codes: G09G 3/3648 using an active matrix G09G3/367 - G09G3/3696 take precedence

Abstract

A display, a method of controlling contrast of a liquid crystal display, and a liquid crystal display. The display includes a liquid crystal panel and a controller for controlling contrast voltage to the liquid crystal panel. The display further includes a temperature sensor operably attached to the controller. A display contrast of the liquid crystal panel is based on the contrast voltage. The contrast voltage is based on a sensed temperature of the temperature sensor. The method includes sensing a temperature. A contrast voltage to the liquid crystal display is controlled based on the sensed temperature. The liquid crystal display includes means for sensing a temperature; and means for controlling contrast voltage to the liquid crystal display based on the sensed temperature.

Claims

1. A display comprising:

a liquid crystal panel;

a controller for controlling contrast voltage to the liquid crystal panel; and

a temperature sensor operably attached to the controller;

wherein a display contrast of the liquid crystal panel is based on the contrast voltage;

wherein the contrast voltage is based on a sensed temperature of the temperature sensor.

2. The display of claim 1 wherein the contrast voltage is inversely proportional to the sensed temperature.

3. The display of claim 1 wherein the liquid crystal display comprises a dialing keypad.

4. The display of claim 1 wherein the controller pulse width modulates the contrast voltage.

5. The display of claim 1 wherein the display is operably attached to a telematics unit.

6. The display of claim 5 wherein the telematics unit is selected from a group consisting of the temperature sensor, a time sensor, an ambient light sensor, and a global positioning system.

7. The display of claim 6 further comprising a display backlight operably attached to the telematics unit;

wherein the display backlight operates based at least one of the time and date sensor, the ambient light sensor, and the GPS unit.

8. A method of controlling contrast of a liquid crystal display, the method comprising:

sensing a temperature; and

controlling contrast voltage to the liquid crystal display based on the sensed temperature.

9. The method of claim 8 wherein the contrast voltage is inversely proportional to the sensed temperature.

10. The method of claim 8 wherein the liquid crystal display comprises a dialing keypad.

11. The method of claim 8 further comprising pulse width modulating the contrast voltage.

12. The method of claim 8 further comprising backlighting the liquid crystal display.

13. The method of claim 12 wherein backlighting the liquid crystal display comprises sensing at least one of time, date, ambient light, and global position.

14. The method of claim 8 further comprising controlling temperature of the liquid crystal display.

15. A liquid crystal display comprising:

means for sensing a temperature; and

means for controlling contrast voltage to the liquid crystal display based on the sensed temperature.

16. The display of claim 15 further comprising means for pulse width modulating the contrast voltage.

17. The display of claim 15 further comprising means for backlighting the liquid crystal display.

18. The display of claim 15 further comprising means for controlling temperature of the liquid crystal display.