INTERACTIVE INPUT SYSTEM AND INFORMATION INPUT METHOD THEREFOR

• US 20110242060A1
• Filed: 04/01/2010
• Published: 10/06/2011
• Est. Priority Date: 04/01/2010
• 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: Radke, Tim, McGibney, Grant
• Granted Patent: US 9,189,086 B2
• Time in Patent Office: Days
• US Class Current: 345/179
• CPC Class Codes: G06F 3/03545 Pens or stylus
• CPC Class Codes: G06F 3/0425 using a single imaging device like a video camera for tracking the absolute position of a single or a plurality of objects with respect to an imaged reference surface, e.g. video camera imaging a display or a projection screen, a table or a wall surface, on which a computer generated image is displayed or projected tracking a projected light spot to determine a position on a display surface G06F3/0386
• CPC Class Codes: G06F 3/0428 by sensing at the edges of the touch surface the interruption of optical paths, e.g. an illumination plane, parallel to the touch surface which may be virtual sensing beam interruptions in a planar beam grid of an optical touch-screen G06F3/0421

Abstract

An interactive input system comprises at least one imaging assembly having a field of view looking into a region of interest and capturing image frames and processing structure in communication with the at least one imaging assembly. When a pointer exists in captured image frames, the processing structure demodulates the captured image frames to determine frequency components thereof and examines the frequency components to determine at least one attribute of the pointer.

Claims

1. An interactive input system comprising:

at least one imaging assembly having a field of view looking into a region of interest and capturing image frames; and

processing structure in communication with the at least one imaging assembly, when a pointer exists in captured image frames, said processing structure demodulating the captured image frames to determine frequency components thereof and examining the frequency components to determine at least one attribute of said pointer.

2. The interactive input system of claim 1, wherein during demodulating the processing structure applies a transform to the captured image frames.

3. The interactive input system of claim 1, wherein the pointer is a pen tool emitting modulated radiation into the region of interest.

4. The interactive input system of claim 3, wherein the modulated radiation emitted by the pen tool is infrared radiation.

5. The interactive input system of claim 1, wherein the attribute comprises any one of pointer input colour and pointer functionality.

6. The interactive input system of claim 5, wherein the pointer functionality is any of right mouse click, left mouse click, and eraser.

7. The interactive input system of claim 1, wherein the at least one imaging assembly comprises at least two imaging assemblies.

8. The interactive input system of claim 7, wherein during demodulating the processing structure applies a transform to the captured image frames.

9. The interactive input system of claim 7, wherein the pointer is a pen tool emitting modulated radiation into the region of interest.

10. The interactive input system of claim 7, further comprising at least one light source configured for emitting radiation into the region of interest.

11. The interactive input system of claim 10, wherein the at least one light source is cycled between on and off states.

12. The interactive input system of claim 11, wherein the at least one imaging assembly captures successive image frames, one image frame being captured when the at least one light source is in the on state and one image frame being captured when the at least one light source is in the off state.

13. The interactive input system of claim 11, wherein said processing structure subtracts image frames captured when the at least one light source is in the off state from image frames captured when at least one light source is in the on state to form difference image frames, sums the difference image frames to form a composite image frame, and determines a location of the pointer in the composite image frame.

14. The interactive input system of claim 13, wherein said processing structure further defines an analysis region associated with the pointer location, and applies the analysis region to the captured image frames for carrying out the examining.

15. The interactive input system of claim 9, wherein the pen tool comprises a pressure sensitive tip, and the pen tool further modulates emitted modulated radiation according to tip pressure.

16. The interactive input system of claim 10, wherein each of the imaging assemblies comprises at least two light sensors having generally identical views of the region of interest and capturing the image frames, the at least two light sensors having exposure periods that are generally staggered.

17. The interactive input system of claim 7, further comprising a bezel at least partially surrounding the region of interest and having a surface in the field of view of said at least two imaging assemblies.

18. The interactive input system of claim 10, wherein the radiation emitted by the at least one light source is infrared radiation.

19. The interactive input system of claim 9, wherein the modulated radiation emitted by the pen tool is infrared radiation.

20. The interactive input system of claim 7, wherein the attribute comprises any one of pointer input colour and pointer functionality.

21. The interactive input system of claim 20, wherein the pointer functionality is any of right mouse click, left mouse click, and eraser.

22. A method of inputting information into an interactive input system comprising:

capturing image frames of a region of interest; and

when a pointer exists in captured image frames, demodulating the captured image frames to determine frequency components thereof and examining the frequency components to determine at least one attribute of the pointer.

23. The method of claim 22, wherein the demodulating further comprises applying a transform to the captured image frames.

24. The method of claim 22, wherein the pointer is an active pen tool emitting modulated radiation into the region of interest.

25. The method of claim 22, further comprising emitting radiation into the region of interest from at least one light source.

26. The method of claim 25, wherein the at least one light source is cycled between on and off states.

27. The method of claim 26, wherein the captured image frames comprise image frames captured in the on and off states.

28. The method of claim 26, further comprising:

generating a composite image frame by subtracting image frames captured in the off state from image frames captured in the on state to form difference image frames, and summing the difference image frames;

determining a location of the pointer in the composite image frame; and

defining an analysis region associated with the pointer location;

wherein the examining is carried out within the analysis region applied to the captured image frames.

29. The method of claim 22, wherein the attribute is selected from the group consisting of pointer input colour and pointer functionality.

30. The method of claim 29, wherein the pointer functionality is any of right mouse click, left mouse click, and eraser.