Light illumination compensation for mobile computing devices

• US 20090042606A1
• Filed: 08/08/2007
• Published: 02/12/2009
• Est. Priority Date: 08/08/2007
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Palm, Inc. (TCL Technology Group Corp.)
• Inventors: Embler, Gary L.
• Granted Patent: US 8,060,136 B2
• Time in Patent Office: Days
• US Class Current: 455/556.100
• CPC Class Codes: H04M 1/22 Illumination; Arrangements for improving the visibility of characters on dials

Abstract

A mobile computing device includes a housing, a light source, a power circuit, and a processing circuit. The housing is configured to be carried by a user while in use. The power circuit is coupled to the light source. The processing circuit is configured to provide control signals to the power circuit to illuminate the light source. The processing circuit is configured to count the illuminations of the light source, to store usage data based on the counted illuminations, and to adjust the control signals based on the usage data.

Claims

1. A mobile computing device, comprising:

a housing configured to be carried by a user while in use;

a light source;

a power circuit coupled to the light source; and

a processing circuit configured to provide control signals to the power circuit to illuminate the light source, wherein the processing circuit is configured to count the illuminations of the light source, to store usage data based on the counted illuminations, and to adjust the control signals based on the usage data.

2. The mobile computing device of claim 1, wherein the light source comprises a light emitting diode.

3. The mobile computing device of claim 2, wherein the light source comprises a plurality of different-colored light emitting diodes configured to emit substantially white light.

4. The mobile computing device of claim 3, wherein the power circuit comprises a plurality of power output lines, each power output line coupled to a different one of the plurality of different-colored light emitting diodes, wherein the processing circuit is configured to provide control signals which independently control the different light emitting diodes, wherein at least one of the different light emitting diodes is controlled based on the usage data.

5. The mobile computing device of claim 4, wherein the processing circuit is configured to determine a chromaticity shift in light provided by the different light emitting diodes based on the usage data and to control the different light emitting diodes to correct for the chromaticity shift.

6. The mobile computing device of claim 1, wherein the usage data is based on a quantity of illuminations over a lifetime of the light source.

7. The mobile computing device of claim 1, wherein the usage data is based on a quantity of illuminations over a predetermined period of time less than 1 hour.

8. The mobile computing device of claim 1, further comprising a digital camera configured to capture an image.

9. The mobile computing device of claim 8, wherein the light source is configured to provide a flash.

10. The mobile computing device of claim 8, wherein the light source is configured to provide a continuous illumination.

11. The mobile computing device of claim 1, further comprising a flat-screen display, wherein the light source is configured to illuminate the flat-screen display.

12. The mobile computing device of claim 1, wherein the light source comprises a white phosphor light emitting diode.

13. The mobile computing device of claim 1, wherein the mobile computing device comprises a display fixed in a coplanar or parallel plane with a plurality of input devices.

14. The mobile computing device of claim 1, further comprising a wireless telephone.

15. The mobile computing device of claim 1, wherein the processing circuit is configured to operate a plurality of personal information management applications and to synchronize the personal information management applications with a remote computer.

16. A method of compensating for chromaticity shift in a light source, comprising:

generating control signals in a mobile computing device to illuminate a plurality of different-colored light-emitting diodes to emit substantially white light;

storing usage data based on the usage of the light emitting diodes; and

independently adjusting the control signals to at least one of the light-emitting diodes to produce the substantially white light based on the usage data.

17. The method of claim 16, wherein the usage data is based on at least one of a quantity of usage over a lifetime of the light source and a quantity of usage over a predetermined period of time less than 1 hour.

18. A digital camera phone, comprising:

a housing configured to be carried by a user while in use;

a wireless telephone circuit configured for cellular communication;

a digital camera;

a light source;

a power circuit coupled to the light source; and

a processing circuit configured to provide control signals to the power circuit to illuminate the light source and to variably adjust the intensity of the light source.

19. The digital camera phone of claim 18, wherein the processing circuit is configured to store usage data representing usage of the light source and to variably adjust the control signals based on the usage data.

20. The digital camera phone of claim 19, wherein the processing circuit is configured to count the illuminations of the light source and to store the usage data based on the counted illuminations of the light source.

21. The digital camera phone of claim 19, wherein the light source comprises a plurality of different light emitting diodes configured to emit substantially white light, wherein the processing circuit is configured to determine a chromaticity shift in light provided by the plurality of different light emitting diodes based on the usage data and to variably adjust the intensity of at least one of the plurality of different light emitting diodes to compensate for the chromaticity shift.