SYSTEM AND METHOD FOR ACHIEVING OPTIMAL DISPLAY CONTRAST IN A MOBILE COMMUNICATION DEVICE

• US 20070146304A1
• Filed: 03/08/2007
• Published: 06/28/2007
• Est. Priority Date: 11/06/2000
• Status: Active Grant

• Current Assignee: Malikie Innovations Limited (Key Patent Innovations Limited)
• Original Assignee: Marek Reksnis, Phat Tran, Robert Lowles
• Inventors: Lowles, Robert, Tran, Phat, Reksnis, Marek
• Granted Patent: US 7,843,413 B2
• Time in Patent Office: Days
• US Class Current: 345/102
• CPC Class Codes: G06F 3/04897 Special input arrangements or commands for improving display capability
• CPC Class Codes: G09G 2320/0606 Manual adjustment
• CPC Class Codes: G09G 2320/066 for control of contrast
• CPC Class Codes: G09G 3/3406 Control of illumination source illumination devices structurally associated with liquid crystal cells G02F1/1336
• CPC Class Codes: G09G 3/36 using liquid crystals
• CPC Class Codes: H04M 1/22 Illumination; Arrangements for improving the visibility of characters on dials
• CPC Class Codes: H04M 1/72448 with means for adapting the functionality of the device according to specific conditions

Abstract

A method is for calibrating a contrast offset value for an LCD contrast control system in a mobile device. The method includes the steps of adjusting a user contrast setting on the mobile device to a desired optimal values initializing the contrast offset value, determining a contrast ratio of the LCD, and incrementing the contrast offset value until the contrast ratio reaches a peak value.

Claims

1. A method for calibrating a contrast offset value for an LCD contrast control system in a mobile device, comprising:

adjusting a user contrast setting on the mobile device to a desired optimal value;

initializing the contrast offset value;

determining a contrast ratio of the LCD; and

incrementing the contrast offset value until the contrast ratio reaches a peak value.

2. The method of claim 1 wherein the contrast offset value is initialized to zero.

3. The method of claim 1 wherein the contrast offset value is initialized to a predetermined value.

4. The method of claim 1 further comprising:

taking an image of the LCD; and

determining the contrast ratio of the LCD from the image.

5. The method of claim 1 wherein the incrementing step includes:

determining whether the contrast ratio is higher than any previously measured values;

if the contrast ratio is higher than any previously measured values, then saving the contrast offset value and contrast ratio to a memory location, incrementing the contrast offset value, and determining an updated contrast ratio;

if the contrast ratio is not higher than any previously measured values, then determining whether the contrast ratio is a first measured value;

if the contrast ratio if the first measured value, then incrementing the contrast offset value and determining an updated contrast ratio; and

if the contrast ratio is not the first measured value, then setting the contrast offset on the mobile device to the saved contrast offset value.

6. The method of claim 1 wherein the incrementing step includes:

determining whether the contrast ratio is higher than any previously measured values;

if the contrast ratio is higher than any previously measured values, then saving the contrast offset value and contrast ratio to a memory location, incrementing the contrast offset value, and determining an updated contrast ratio;

if the contrast ratio is not higher than any previously measured values, then determining whether the contrast ratio is a first measured value;

if the contrast ratio is the first measured value, then incrementing the contrast offset value and determining an updated contrast ratio;

if the contrast ratio is not the first measured value, then determining whether the contrast ratio is substantially less than the saved contrast ratio;

if the contrast ratio is not substantially less than the saved contrast ratio, then incrementing the contrast offset value and determining an updated contrast ratio; and

if the contrast ratio is substantially less than the save contrast ratio, then setting the contrast offset value on the mobile device to the saved contrast offset value.

7. A method for calibrating a contrast scale value for an LCD contrast control system in a mobile device, comprising:

adjusting a user contrast setting on the mobile device to a highest setting;

initializing the contrast scale value;

determining a contrast ratio of the LCD; and

incrementing or decrementing the contrast scale value until the contrast ratio reaches a desired maximum value.

8. The method of claim 7 wherein the contrast scale value is incremented or decremented by a scale calibration step value.

9. The method of claim 8 further comprising:

initializing the calibration step value to a pre-selected maximum step value.

10. The method of claim 8 wherein the scale calibration step value is reduced each time the contrast scale value is incremented or decremented.

11. The method of claim 10 wherein the scale calibration step is reduced by one half each time the contrast value is incremented or decremented.

12. The method of claim 7 wherein the step of incrementing or decrementing includes:

determining whether the contrast ratio of the LCD is substantially equivalent to a desired maximum value;

if the contrast ratio is substantially equivalent to the desired maximum value, then saving the contrast scale value to the mobile device;

if the contrast ratio is not substantially equivalent to the desired maximum, then determining whether the contrast ratio of the LCD is above or below the desired maximum value;

if the contrast ratio is not substantially equivalent to the desired maximum, and if the contrast ratio of the LCD is above the desired maximum value, then decrementing the contrast scale value until the contrast ratio reached the desired maximum value; and

if the contrast ratio is not substantially equivalent to the desired maximum, and if the contrast ratio of the LCD is below the desired maximum value, then incrementing the contrast scale value until the contrast ratio reaches the desired maximum value.

13. The method of claim 7 wherein the step of incrementing or decrementing includes:

determining whether the contrast ratio of the LCD is within a pre-selected tolerance range of a desired maximum value;

If the contrast ratio is within the pre-selected tolerance range of the desired maximum value, then saving the contrast scale value to the mobile device;

if the contrast ratio is not within the pre-selected tolerance range of the desired maximum value, then determining whether the contrast ratio of the LCD is above or below the desired maximum value;

if the contrast ratio is not within the pre-selected tolerance range of the desired maximum value, and if the contrast ratio of the LCD is above the desired maximum value, then decrementing the contrast scale value until the contrast ratio reached the desired maximum value; and

if the contrast ratio is not within the pre-selected tolerance range of the desired maximum value, and if the contrast ratio of the LCD is below the desired maximum value, then incrementing the contrast scale value until the contrast ratio reaches the desired maximum value.

14. The method of claim 7 wherein the contrast scale value is initialized to zero.

15. The method of claim 7 further comprising:

taking an image of the LCD; and

determining the contrast ratio of the LCD from the image.

16. A method for calibrating a backlight adjustment value for an LCD contrast control system in a mobile device, comprising:

turning on a LCD backlight;

initialize the backlight adjustment value;

adjusting a user contrast setting on the mobile device to a pre-calibrated optimal value;

determining a contrast ratio of the LCD; and

incrementing the backlight adjustment value until the contrast ratio reaches a peak value.

17. The method of claim 16 wherein the backlight adjustment value is initialized to zero.

18. The method of claim 16 further comprising:

taking an image of the LCD; and

determining the contrast ratio of the LCD from the image.

19. The method of claim 16 wherein the incrementing step includes:

determining whether the contrast ratio is higher than any previously measured values;

if the contrast ratio is higher than any previously measured values, then saving the backlight adjustment value and contrast ratio to a memory location, incrementing the backlight adjustment value, and determining an updated contrast ratio;

if the contrast ratio is not higher than any previously measured values, then determining whether the contrast ratio is a first measured value;

if the contrast ratio is the first measured value, then incrementing the backlight adjustment value and determining an updated contrast ratio; and

if the contrast ratio is not the first measured value, then setting the backlight adjustment value on the mobile device to the saved backlight adjustment value.

20. The method of claim 16, wherein the step of incrementing the backlight adjustment value until the contrast ratio reaches a peak value is performed by a method comprising the steps of:

determining whether the contrast ratio is higher than any previously measured values;

if the contrast ratio is higher than any previously measured values, then saving the backlight adjustment value and contrast ratio to a memory location, incrementing the backlight adjustment value, and determining an updated contrast ratio;

if the contrast ratio is not higher than any previously measured values, then determining whether the contrast ratio is a first measured value;

if the contrast ratio if the first measured value, then incrementing the backlight adjustment value and determining an updated contrast ratio;

if the contrast ratio is not the first measured value, then determining whether contrast ratio is substantially less than the saved contrast ratio;

if the contrast ratio is not substantially less than the saved contrast ratio, then incrementing the backlight adjustment value and determining an updated contrast ratio; and

if the contrast ratio is substantially less than the save contrast ratio, then setting the backlight adjustment value on the mobile device to the saved backlight adjustment.