INTERACTIVE INPUT SYSTEM AND PEN TOOL THEREFOR

• US 20110242006A1
• 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: THOMPSON, SEAN, Holmgren, David, McGibney, Grant
• Granted Patent: US 8,872,772 B2
• Time in Patent Office: Days
• US Class Current: 345/173
• CPC Class Codes: G06F 3/03545 Pens or stylus
• 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

A pen tool for use with a machine vision interactive input system comprises an elongate body and a tip arrangement at one end of the body, an end surface of the body at least partially about the tip arrangement carrying light reflective material that is visible to at least one imaging assembly of the interactive input system when the pen tool is angled.

Claims

1. A pen tool for use with a machine vision interactive input system comprising:

an elongate body; and

a tip arrangement at one end of said body, an end surface of said body at least partially about said tip arrangement carrying light reflective material that is visible to at least one imaging assembly of said interactive input system when the pen tool is angled.

2. A pen tool according to claim 1 wherein said end surface surrounds said tip arrangement and wherein the end surface carries an annular ring of light reflective material.

3. A pen tool according to claim 2 wherein a side surface of said body adjacent said tip arrangement carries at least one band of light reflective material that extends around said body.

4. A pen tool according to claim 3 wherein said light reflective material is retro-reflective material.

5. A pen tool according to claim 4 wherein the at least one band of light reflective material extending around said body is continuous.

6. A pen tool according to claim 5 wherein the side surface of said body carries a plurality of spaced bands of light reflective material, each band extending around said body.

7. A pen tool according to claim 3 wherein said at least one band of light reflective material is patterned.

8. A pen tool according to claim 7 wherein said at least one band of light reflective material is interrupted at generally equal circumferentially spaced locations.

9. A pen tool according to claim 2 wherein the light reflective material on said end surface is patterned.

10. A pen tool according to claim 9 wherein the light reflective material on said end surface is interrupted at generally equal space locations.

11. A pen tool according to claim 2 wherein said tip arrangement comprises a nib and wherein light reflective material substantially surrounds said nib.

12. A pen tool according to claim 11 wherein a side surface of said body adjacent said tip arrangement carries at least one band of light reflective material that extends around said body.

13. A pen tool according to claim 12 wherein the side surface of said body carries a plurality of spaced bands of light reflective material.

14. A pen tool according to claim 12 wherein said at least one band of light reflective material is patterned.

15. A pen tool according to claim 14 wherein said at least one band is interrupted at generally equal circumferentially spaced locations.

16. A pen tool according to claim 2 wherein said tip arrangement comprises a first portion that is in general axial alignment with said body, a generally conical portion extending from said first portion and narrowing in a direction away from said first portion and a nib at the narrow end of said conical portion.

17. A pen tool according to claim 16 wherein said light reflective material is provided on a side surface of said first portion.

18. A pen tool according to claim 17 further comprising a generally light transparent cover over the light reflective material on the outer surface of said first portion.

19. A pen tool for use with a machine vision interactive input system comprising:

an elongate, generally cylindrical body; and

a tip arrangement extending from one end of said body, said tip arrangement comprising a generally conical portion that narrows in a direction away from said body and a nib at the narrow end of said conical portion, wherein an end surface of said body adjacent said tip arrangement carries an annular ring of light reflective material that is visible to at least one imaging assembly of said interactive input system when the pen tool is angled.

20. A method of identifying a pointer in a machine vision interactive input system comprising a region of interest surrounded by a bezel and at least one imaging assembly having a field of view looking into said region of interest, said method comprising:

capturing image frames; and

processing the image frames to detect the presence of a pointer and to detect the presence of a signature that is distinctive of the bezel representative of a pen tool.

21. The method of claim 20 wherein during processing of the image frames to detect the presence of a signature, the image frames are processed to detect pen tool reflections in regions of the image frames beyond the limits of the bezel.

22. The method of claim 21 wherein processing of the image frames to detect the presence of a signature comprises dividing a background image frame from each captured image frame to form a difference image frame and examining the different image frames to detect pen tool reflections in regions of the image frames beyond the limits of the bezel.

23. The method of claim 22 wherein processing of the image frames to detect the presence of a signature further comprises, after said subtracting, determining the visible end limits of the bezel in each difference image frame and masking regions of each difference image frame beyond the end limits.

24. The method of claim 23 wherein the end limit determining is performed one of manually or automatically.

25. The method of claim 23 wherein said examining comprises thresholding each difference image frame to detect the presence of reflections therein and when reflections are present, determining whether the reflections appear in regions beyond the limits of the bezel.

26. An interactive input system comprising:

a region of interest surrounded by a bezel;

at least one imaging assembly having a field of view looking into the region of interest and seeing said bezel; and

processing structure processing image frames captured by said at least one imaging assembly to detect the presence of a pointer and to detect the presence of a signature that is distinctive of the bezel representative of a pen tool.