INTERACTIVE INPUT SYSTEM AND ILLUMINATION SYSTEM THEREFOR

• US 20110169727A1
• Filed: 02/19/2010
• Published: 07/14/2011
• Est. Priority Date: 01/13/2010
• Status: Active Grant

• Current Assignee: Smart Technologies ULC (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Smart Technologies ULC (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Akitt, Trevor Mitchell
• Granted Patent: US 8,624,835 B2
• Time in Patent Office: Days
• US Class Current: 345/156
• CPC Class Codes: G06F 3/0421 by interrupting or reflecting a light beam, e.g. optical touch-screen

Abstract

An interactive input system includes at least one illumination source emitting radiation into a region of interest; at least one imaging assembly capturing image frames of the region of interest, the at least one illumination source being in the field of view of the at least one imaging assembly; and a controller communicating with the at least one illumination source, the controller controlling the intensity of radiation emitted by the at least one illumination source during image frame capture.

Claims

1. An interactive input system comprising:

at least one illumination source emitting radiation into a region of interest;

at least one imaging assembly capturing image frames of said region of interest, said at least one illumination source being in the field of view of said at least one imaging assembly; and

a controller communicating with said at least one illumination source, said controller controlling the intensity of radiation emitted by said at least one illumination source during image frame capture.

2. The interactive input system of claim 1, wherein the intensity of radiation emitted by the at least one illumination source during image frame capture is reduced by the controller.

3. The interactive input system of claim 2, wherein the intensity of emitted radiation is reduced to a level approximating the background in image frames captured by the at least one imaging device.

4. The interactive input system of claim 3, wherein the intensity of emitted radiation is reduced to a level approximating backlight illumination provided to said region of interest.

5. The interactive input system of claim 4 comprising:

a plurality of imaging assemblies capturing images of said region of interest from different vantages;

at least one illumination source adjacent each imaging assembly; and

a controller for each illumination source.

6. The interactive input system of claim 5, wherein the controller is responsive to its associated imaging assembly during image frame capture thereby to illuminate generally fully the associated illumination source and is responsive to its associated imaging assembly during image frame capture by other imaging assemblies to illuminate the associated illumination source at a reduced level.

7. The interactive input system of claim 6 comprising a plurality of illumination sources associated with each imaging assembly.

8. The interactive input system of claim 6, wherein said controller is responsive to an image sensor of said imaging assembly during image frame capture and is responsive to a processor of said imaging assembly when illuminating the associated illumination source at a reduced level.

9. The interactive input system of claim 1, wherein said region of interest is generally rectangular, imaging assemblies are positioned adjacent at least two corners of said region of interest, and an illumination source is positioned adjacent each imaging assembly.

10. The interactive input system of claim 9, further comprising a reflective bezel surrounding the region of interest.

11. The interactive input system of claim 10, wherein said reflective bezel is retro-reflective.

12. The interactive input system of claim 11, wherein an imaging assembly is positioned adjacent each corner of said region of interest.

13. The interactive input system of claim 11, comprising a plurality of illumination sources associated with each imaging assembly.

14. The interactive input system of claim 13, wherein said illumination sources are infrared sources.

15. The interactive input system of claim 11, wherein the intensity of radiation emitted by the at least one illumination source during image frame capture is reduced by the controller.

16. The interactive input system of claim 15, wherein the intensity of emitted radiation is reduced to a level approximating backlight illumination provided to said region of interest by said bezel.

17. The interactive input system of claim 16, wherein each controller is responsive to its associated imaging assembly during image frame capture thereby to illuminate generally fully the associated illumination source and is responsive to its associated imaging assembly during image frame capture by other imaging assemblies to illuminate the associated illumination source at a reduced level.

18. The interactive input system of claim 17, comprising a plurality of illumination sources associated with each imaging assembly.

19. The interactive input system of claim 17, wherein each controller is responsive to an image sensor of said imaging assembly during image frame capture and is responsive to a processor of said imaging assembly when illuminating the associated illumination source at a reduced level.

20. A method of controlling image capture in an interactive input system, the method comprising:

causing at least one illumination source to emit radiation into a region of interest;

causing at least one imaging assembly to capture image frames of said region of interest, said at least one illumination source being in the field of view of said at least one imaging assembly; and

controlling the intensity of radiation emitted by said at least one illumination source during image frame capture.

21. The method of claim 20, wherein said controlling comprises reducing the intensity of radiation emitted by said at least one illumination source.

22. The method of claim 21, wherein said controlling comprises reducing the intensity of radiation emitted by said at least one illumination source to a level approximating the background of captured image frames.