Monochromatic field sequential liquid crystal display

• US 20050035940A1
• Filed: 02/24/2004
• Published: 02/17/2005
• Est. Priority Date: 08/12/2003
• Status: Active Grant

• Current Assignee: Malikie Innovations Limited (Key Patent Innovations Limited)
• Original Assignee: Blackberry Limited
• Inventors: Lazaridis, Mihal, Griffin, Jason T., Lowles, Robert J.
• Granted Patent: US 7,233,310 B2
• Time in Patent Office: Days
• US Class Current: 345/102
• CPC Class Codes: G02F 1/133622 Colour sequential illumination
• CPC Class Codes: G09G 2310/0235 Field-sequential colour display
• CPC Class Codes: G09G 3/3406 Control of illumination source illumination devices structurally associated with liquid crystal cells G02F1/1336
• CPC Class Codes: H04M 1/22 Illumination; Arrangements for improving the visibility of characters on dials
• CPC Class Codes: H04M 1/72403 with means for local support of applications that increase the functionality
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A device and a method are provided for establishing a monochromatic background light source in an electronic device with a field sequential liquid crystal display. The device and method provide for the continuous illumination of one or more of a plurality of color backlights of a field sequential liquid crystal display to provide a monochromatic source of light behind the liquid crystal layer of the display. The intensities of the one or more of the plurality of color backlights may be selected to achieve a user selected color, or the intensities may be chosen to reduce power consumption. The monochromatic mode may be selected while in another mode of operation.

Claims

1. An electronic device, comprising:

a field sequential liquid crystal display with a liquid crystal layer and a plurality of color backlights; and

a control module for controlling the continuous illumination of one or more of the plurality of color backlights to provide a monochromatic source of light behind the liquid crystal layer.

2. The device of claim 1, wherein individual intensities of the one or more of the plurality of backlights are selected to achieve a user selected color.

3. The device of claim 1, wherein individual intensities of the one or more of the plurality of backlights are minimized while providing a user acceptable contrast level.

4. The device of claim 1, wherein a output intensity of one or more of the plurality of backlights is set to zero.

5. The device of claim 1, wherein only one backlight is illuminated.

6. The device of claim 5, wherein the backlight with the lowest power consumption is selectively illuminated.

7. The device of claim 1, wherein the continuous illumination of the one or more of the plurality of backlights is one of a plurality of display modes that can be selected by the user.

8. The device of claim 1, wherein the frame rate frequency of the field sequential liquid crystal display is set to between about 24 and about 70 Hertz.

9. The device of claim 1, wherein the frame rate frequency of the field sequential liquid crystal display is set to between about 24 and about 40 Hertz.

10. A method for providing a monochromatic background display mode in an electronic device having a field sequential liquid crystal display with a plurality of color backlights, comprising:

continuously illuminating one or more of the plurality of color backlights of the field sequential liquid crystal display.

11. The method of claim 10, wherein individual intensities of the one or more of the plurality of backlights are selected to achieve a user selected color.

12. The method of claim 10, wherein the individual intensities of the one or more of the plurality of backlights are minimized while providing a user acceptable contrast level.

13. The method of claim 10, wherein the output intensity of one or more of the plurality of backlights is set to zero.

14. The method of claim 10, wherein only one backlight is illuminated.

15. The method of claim 14, wherein the backlight with the lowest power consumption is selectively illuminated.

16. The method of claim 10, wherein the continuous illumination of one or more of the plurality of backlights is one of a plurality of display modes that can be selected by the user.

17. An electronic device, comprising:

a field sequential liquid crystal display with a liquid crystal layer and a plurality of color backlights; and

a control module for controlling the continuous illumination of one or more of the plurality of backlights to provide a monochromatic source of light behind the liquid crystal layer

wherein the frame rate frequency of the field sequential liquid crystal display is set to between about 24 and about 40 Hertz, and the individual intensities of the one or more of the plurality of backlights are selected to achieve a user selected color.