Remote control systems that can distinguish stray light sources

• US 7,655,937 B2
• Filed: 07/16/2008
• Issued: 02/02/2010
• Est. Priority Date: 11/07/2006
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: King, Nicholas Vincent, Hotelling, Steven Porter, Kerr, Duncan Robert, Low, Wing Kong
• Primary Examiner(s): Sohn; Seung C
• Application Number:
  US12/174,542
• Publication Number:
  US 20080272272A1
• Time in Patent Office: 566 Days
• Field of Search: 250/226, 250/578.1, 250/559.29, 345/158, 345/163, 345/169, 340/825.72, 340/825.57
• US Class Current: 250/578.1
• CPC Class Codes: G01J 1/16 using electric radiation detectors G01J1/20 takes precedence
• CPC Class Codes: G01J 1/4204 with determination of ambient light solar light G01J2001/4266
• CPC Class Codes: G01J 1/44 Electric circuits for command of an exposure part G03B7/02
• CPC Class Codes: G08C 2201/32 Remote control based on movements, attitude of remote control device
• CPC Class Codes: G08C 23/04 using light waves, e.g. infrared
• CPC Class Codes: H04N 21/42204 User interfaces specially adapted for controlling a client device through a remote control device; Remote control devices therefor constructive details of casings for the remote control device H01H9/0235; user interfaces for controlling a tuning device of a television receiver through a remote control H03J9/00; remote control of peripheral devices connected to a television receiver through the remote control device of the television receiver H04B1/205
• CPC Class Codes: H04N 21/42221 Transmission circuitry, e.g. infrared [IR] or radio frequency [RF]

Abstract

Remote control systems that can distinguish predetermined light sources from stray light sources, e.g., environmental light sources and/or reflections are provided. The predetermined light sources can be disposed in asymmetric substantially linear or two-dimensional patterns. The predetermined light sources also can output waveforms modulated in accordance with one or more signature modulation characteristics. The predetermined light sources also can output light at different signature wavelengths.

Claims

1. A method for distinguishing at least one predetermined light source from stray light sources, the method comprising:

continuously modulating an output waveform of the at least one predetermined light source in accordance with at least one signature modulation characteristic;

detecting light from light sources using a photodetector;

generating photodetector data representative of the detected light; and

identifying at least one light source from the photodetector data that exhibits the at least one signature modulation characteristic.

2. The method of claim 1, wherein modulating an output waveform of the at least one predetermined light source comprises turning the at least one predetermined light source ON and OFF in accordance with the at least one signature modulation characteristic.

3. The method of claim 1, wherein modulating an output waveform of the at least one predetermined light source comprises adjusting signal strength of the output waveform in a predetermined manner in accordance with the at least one signature modulation characteristic.

4. The method of claim 1, wherein:

the at least one predetermined light source comprises at least first and second predetermined light sources;

modulating an output waveform of the at least one predetermined light source comprises modulating an output waveform of the first predetermined light source in accordance with at least a first signature modulation characteristic, and modulating an output waveform of the second predetermined light source in accordance with at least a second signature modulation characteristic; and

identifying at least one light source comprises identifying a first light source that exhibits the first signature modulation characteristic, and identifying a second light source that exhibits the second signature modulation characteristic.

5. The method of claim 1, wherein the at least one signature modulation characteristic comprises a predetermined frequency at which the output waveform of the at least one predetermined light source is modulated, a predetermined duty cycle at which the output waveform of the at least one predetermined light source is modulated, a phase shift, or a combination thereof.

6. The method of claim 1, wherein identifying at least one light source comprises demodulating the photodetector data in accordance with the at least one signature modulation characteristic.

7. The method of claim 1, wherein:

the photodetector comprises a two-dimensional position sensitive diode; and

detecting light from light sources comprises detecting light from light sources using the two-dimensional position sensitive diode.

8. The method of claim 1, further comprising determining the position of the photodetector with respect to the identified at least one light source.

9. The method of claim 1, wherein:

the at least one predetermined light sources comprises a plurality of predetermined light sources;

the plurality of predetermined light sources are disposed in a target pattern; and

the identifying at least one light source is based on the target pattern.

10. A system comprising:

a first predetermined light source configured to emit light at a first signature wavelength;

a second predetermined light source configured to emit light at a second signature wavelength, wherein the first signature wavelength is different than the second signature wavelength; and

a remote control having a photodetector module, wherein the photodetector module is configured to detect the first and second signature wavelengths of light.

11. The system of claim 10, wherein the photodetector module comprises first and second photodetectors, wherein the first photodetector is configured to detect the first wavelength of light and the second photodetector is configured to detect the second wavelength of light.

12. The system of claim 10, wherein the photodetector module comprises an array of interleaved pixels, wherein a first portion of the interleaved pixels are configured to detect the first wavelength of light and a second portion of the interleaved pixels is configured to detect the second wavelength of light.

13. The system of claim 12, wherein the first and second portions form alternating rows of the array.

14. The system of claim 12, wherein the first and second portions form alternating columns of the array.

15. The system of claim 12, wherein the first and second portions form a checkerboard pattern.

16. The system of claim 10, wherein the first and second predetermined light sources are disposed in a display.

17. The system of claim 10, further comprising a remote control within which the photodetector module is disposed.

18. The system of claim 10, further comprising circuitry configured to determine whether the remote control is upside-down.

19. The system of claim 10, further comprising circuitry configured to determine the position of the remote control with respect to the first and second predetermined light sources.