AMBIENT LIGHT SENSOR WITH REDUCED SENSITIVITY TO NOISE FROM INFRARED SOURCES

• US 20120056091A1
• Filed: 11/15/2011
• Published: 03/08/2012
• Est. Priority Date: 09/25/2008
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Mahowald, Peter H.
• Granted Patent: US 8,779,345 B2
• Time in Patent Office: Days
• US Class Current: 250/340
• CPC Class Codes: G01J 1/02 Details
• CPC Class Codes: G01J 1/0219 Electrical interface; User interface
• CPC Class Codes: G01J 1/029 Multi-channel photometry
• CPC Class Codes: G01J 1/04 Optical or mechanical part supplementary adjustable parts
• CPC Class Codes: G01J 1/0407 Optical elements not provided otherwise, e.g. manifolds, windows, holograms, gratings
• CPC Class Codes: G01J 1/1626 Arrangements with two photodetectors, the signals of which are compared
• CPC Class Codes: G01J 1/32 adapted for automatic variation of the measured or reference value regulation of light intensity G05D25/00

Abstract

Systems and methods are provided for detecting ambient light with reduced sensitivity to infrared sources. An electronic device may include an infrared sensor, an ambient light sensor, a decoder, and a processor. The infrared sensor may detect an intensity of infrared light. The ambient light sensor may be configured to detect incident light and to generate an electronic signal indicative of an intensity of visible light. The decoder may be configured to receive the intensity of infrared light and to generate an intensity of decoded infrared light. The processor, which may be coupled to the decoder and the ambient light sensor, may be configured to substitute an alternate electronic signal for the electronic signal if the intensity of infrared light exceeds a threshold amount.

Claims

1-7. -7. (canceled)

8. A method for controlling an electronic device comprising:

detecting an intensity of all light at substantially any wavelength;

detecting an intensity of infrared light at near-infrared wavelengths;

generating an electronic signal indicative of an intensity of ambient light based on a difference between the intensity of all light and the intensity of infrared light; and

generating a first control signal based on the electronic signal and, if the intensity of infrared light exceeds a threshold intensity, generating a second control signal based on an alternate electronic signal.

9. The method of claim 8 further comprising:

causing an illumination mechanism associated with the electronic device to respond to at least one of the first and second control signals.

10. The method of claim 9 wherein causing comprises increasing a brightness of the illumination mechanism.

11. The method of claim 9, wherein the illumination mechanism comprises a keyboard.

12. The method of claim 9, wherein the illumination mechanism comprises a display.

13. The method of claim 9, wherein the illumination mechanism comprises an indicator light for visual diagnostics.

14. The method of claim 8, wherein the alternate electronic signal is a previous value of the electronic signal.

15. The method of claim 8 further comprising:

restoring the electronic signal if the intensity of infrared light is below the threshold intensity.

16-18. -18. (canceled)