Waveguide Configurations for Minimising Substrate Area

• US 20080106527A1
• Filed: 11/05/2007
• Published: 05/08/2008
• Est. Priority Date: 11/06/2006
• Status: Abandoned Application

• Current Assignee: Zetta Research and Development LLC - RPO Series (Zetta Research, LLC)
• Original Assignee: RPO Pty Limited (RPO, Inc.)
• Inventors: Holloway, Warwick, Kukulj, Dax, Maxwell, Ian, Charters, Robert, Cornish, Benjamin
• Application Number:
  US11/935,124
• Publication Number:
  US 20080106527A1
• Time in Patent Office: Days
• US Class Current: 345/176
• CPC Class Codes: G02B 6/12004 Combinations of two or more optical elements
• CPC Class Codes: G02B 6/1245 Geodesic lenses
• CPC Class Codes: G02B 6/125 Bends, branchings or intersections
• CPC Class Codes: G06F 3/0421 by interrupting or reflecting a light beam, e.g. optical touch-screen

Abstract

The invention describes various optical waveguide layouts with reduced substrate area, with particular application to reducing bezel width in optical touch systems. In certain preferred embodiments the optical waveguide layouts include a plurality of waveguide crossings.

Claims

1. A waveguide assembly for passing signals to or from an input area of an optical touch input device, said assembly comprising a plurality of waveguides extending between a respective plurality of lenses and a respective signal detector or signal source, wherein at least one waveguide crosses over at least one other waveguide in said assembly.

2. A waveguide assembly as claimed in claim 1 wherein said waveguides cross each other at an angle sufficiently large to minimise signal interference or cross talk between said waveguides.

3. A waveguide assembly as claimed in claim 2 wherein the size of said angle is a function of:

i) the materials comprising said waveguides; and

/or

ii) the wavelength of an optical signal transmitted by said waveguides.

4. A waveguide assembly as claimed in claim 2 wherein said angle is greater than 10 degrees.

5. A waveguide assembly as claimed in claim 2 wherein said angle is greater than 40 degrees.

24. A method according to claim 12 wherein a waveguide assembly as claimed in anyone of the preceding claims wherein said plurality of waveguides extend along at least part of their length in a mutually parallel spaced apart array.

6. A waveguide assembly for passing signals to or from an input area of an optical touch input device, said assembly comprising a waveguide fairway defined by a plurality of waveguides that, at least along part of their length, extend in an array to thereby define inner and outer sides of said fairway, wherein waveguides on said outer side of said fairway cross over other waveguides in said allay to said inner side of said fairway for connection to lenses facing said input area of said touch input device.

8. A waveguide assembly as claimed in claim 6 wherein said waveguides are directed towards said outer side of said fairway at substantially the same point along their length.

9. A waveguide assembly as claimed in claim 6 wherein said waveguides are directed towards said outer side of said fairway sequentially at different points along their length.

7. A waveguide assembly for passing signals to or from an input area of an optical touch input device, said assembly comprising a waveguide fairway defined by a plurality of waveguides that, at least along part of their length, extend in an allay to thereby define inner and outer sides of said fairway, wherein each said waveguide at some point along its length is directed toward said outer side of said fairway.

10. A waveguide assembly as claimed in claim 7 wherein said assembly is produced on an L-shaped substrate, said waveguides being formed on two portions of said substrate substantially at right angles to each other, each portion having an array of waveguides for waveguide assembly connection to said respective plurality of lenses.

11. A waveguide assembly according to claim 7 comprising a plurality of waveguide assemblies stacked on top of each other to define a multi-layer waveguide assembly.

12. A waveguide assembly as claimed in claim 7 wherein said plurality of waveguides extend along at least part of their length in a mutually parallel spaced apart array.

13. A method for reducing bezel width in an optical touch input device;

said method comprising the steps of providing a waveguide assembly for passing signals to or from an input area of said optical touch input device, said assembly comprising a plurality of waveguides extending between a respective plurality of lenses and a respective signal detector or signal source, wherein at least one waveguide crosses over at least one other waveguide in said assembly.

18. A method according to claim 13 wherein said assembly is produced on an L-shaped substrate, said waveguides being formed on two portions of said substrate substantially at tight angles to each other;

each portion having an array of waveguides for waveguide assembly connection to said respective plurality of lenses.

19. A method according to claim 13 wherein said waveguides cross each other at an angle sufficiently large to minimise signal interference or cross talk between said waveguides.

20. A method according to claim 19 wherein the size of said angle is a function of:

i) the materials comprising said waveguides; and

/or ii) the wavelength of an optical signal transmitted by said waveguides.

21. A method according to claim 19 wherein said angle is greater than 10 degrees.

22. A method according to claim 19 wherein said angle is greater than 40 degrees.

23. A method according to claim 19 comprising a plurality of waveguide assemblies stacked on top of each other to define a multi-layer waveguide assembly.

14. A method for reducing bezel width in an optical touch input device;

said method comprising the steps of providing a waveguide assembly for passing signals to or from an input area of said optical touch input device, said assembly comprising a waveguide fairway defined by a plurality of waveguides that, at least along part of their length, extend in an array to thereby define inner and outer sides of said fairway, wherein waveguides on said outer side of said fairway cross over other waveguides in said array to said inner side of said fairway for connection to lenses facing said input area of said touch input device.

16. A method according to claim 14 wherein said waveguides are directed towards said outer side of said fairway at substantially the same point along their length.

17. A method according to claim 14 wherein said waveguides are directed towards said outer side of said fairway sequentially at different points along their length.

15. A method for reducing bezel width in an optical touch input device;

said method comprising the steps of providing a waveguide assembly for passing signals to or from an input area of said optical touch input device, said assembly comprising a waveguide fairway defined by a plurality of waveguides that, at least along part of their length, extend in an array to thereby define inner and outer sides of said fairway, wherein each said waveguide at some point along its length is directed toward said outer side of said fairway.