ILLUMINATION DEVICE WITH METALIZED LIGHT-TURNING FEATURES

• US 20110157093A1
• Filed: 12/27/2010
• Published: 06/30/2011
• Est. Priority Date: 12/29/2009
• Status: Active Grant

• Current Assignee: Snaptrack Incorporated (Qualcomm, Inc.)
• Original Assignee: Qualcomm MEMS Technologies Incorporated (Qualcomm, Inc.)
• Inventors: Dhanens, Stephen P., Gousev, Evgeni P., Bita, Ion, Narayanan, Kollengode S.
• Granted Patent: US 8,810,528 B2
• Time in Patent Office: Days
• US Class Current: 345/175
• CPC Class Codes: G02B 26/001 based on interference in an adjustable optical cavity interference filters G02B5/28; devices or arrangements using multiple reflections in spectrometry or monochromators G01J3/26
• CPC Class Codes: G02B 6/0045 by shaping at least a portion of the light guide
• CPC Class Codes: G02B 6/0055 Reflecting element, sheet or layer
• CPC Class Codes: G02B 6/0083 Details of electrical connections of light sources to drivers, circuit boards, or the like
• CPC Class Codes: G02F 1/225 in an optical waveguide structure
• CPC Class Codes: G06F 2203/04103 Manufacturing, i.e. details related to manufacturing processes specially suited for touch sensitive devices
• CPC Class Codes: G06F 2203/04112 Electrode mesh in capacitive digitiser: electrode for touch sensing is formed of a mesh of very fine, normally metallic, interconnected lines that are almost invisible to see. This provides a quite large but transparent electrode surface, without need for ITO or similar transparent conductive material
• CPC Class Codes: G06F 3/0421 by interrupting or reflecting a light beam, e.g. optical touch-screen
• CPC Class Codes: G06F 3/0443 using a single layer of sensing electrodes
• CPC Class Codes: G06F 3/0446 using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes
• CPC Class Codes: Y10T 29/49117 Conductor or circuit manufacturing

Abstract

This disclosure provides systems, methods and apparatus for a front illumination device with metalized light-turning features. In one aspect, an illumination device with integrated touch sensor capability includes a light guide having a metalized light-turning feature and an electrode system for sensing changes to the capacitance between electrodes in the electrode system induced by the proximity of an electrically conductive body, such as a human finger. The metalized light-turning features may be electrically connected to and/or part of the electrode system.

Claims

1. An illumination device with integrated touch-sensing capability comprising:

a light guide having a conductor formed on a light-turning feature; and

a touch-sensing electrode system capable of sensing a change to a capacitance of the conductor induced by the proximity of an electrically conductive body.

2. The illumination device of claim 1, wherein the conductor is formed on a faceted feature on a surface of the light guide.

3. The illumination device of claim 1, wherein the conductor is masked in order to reduce reflections of ambient light from the conductor.

4. The illumination device of claim 3, wherein the conductor is masked with an interferometric structure.

5. The illumination device of claim 4, wherein the interferometric structure is configured to be more reflective of light striking a bottom surface of the interferometric structure than light striking a top surface of the interferometric structure.

6. The illumination device of claim 1, wherein the electrode system is capable of determining a location in an x-y plane of the change to capacitance induced by the proximity of the electrically conductive body.

7. The illumination device of claim 1, further comprising:

a display which can be illuminated by the light guide;

a processor that is configured to communicate with said display, said processor being configured to process image data; and

a memory device that is configured to communicate with said processor.

8. The illumination device as recited in claim 7, further comprising a driver circuit configured to send at least one signal to said display.

9. The illumination device as recited in claim 8, further comprising a controller configured to send at least a portion of said image data to said driver circuit.

10. The illumination device as recited in claim 7, further comprising an image source module configured to send said image data to said processor.

11. The illumination device as recited in claim 10, wherein said image source module comprises at least one of a receiver, transceiver, and transmitter.

12. The illumination device as recited in claim 7, further comprising:

an input device configured to receive input data and to communicate said input data to said processor.

13. The illumination device of claim 1, wherein

the light guide comprises a light-turning layer formed on a substrate;

and

the light-turning feature is formed in the light-turning layer.

14. The illumination device of claim 1, wherein

the touch-sensing electrode system comprises a first electrode extending in one direction and a second electrode extending in another, non-parallel direction;

the first electrode has a gap with two sides formed to prevent the intersection of the first and the second electrodes, the gap breaking the first electrode into a first side and a second side; and

the first and second electrodes are formed on a single surface.

15. The illumination device of claim 14, wherein the first side of the first electrode is electrically connected to the second side of the first electrode across the gap through a conductive bridge and vias formed on both sides of the gap.

16. The illumination device of claim 15, wherein the first and second electrode comprise transparent conductors.

17. The illumination device of claim 15, wherein the conductive bridge is formed on a level below the surface of the first and second electrodes.

18. The illumination device of claim 15, wherein the conductive bridge comprises a reflective conductor.

19. The illumination device of claim 15, wherein the vias comprise a reflective conductor.

20. The illumination device of claim 19, wherein the vias are light-turning features configured to direct light downward out of the light guide.

21. The illumination device of claim 1, wherein the electrically conductive body comprises a human finger.

22. The illumination device of claim 1, wherein the touch-sensing electrode system comprises electrodes formed in two different layers.

23. The illumination device of claim 1, wherein the touch-sensing electrode system is capable of sensing a change to a mutual capacitance.

24. The illumination device of claim 1, wherein the touch-sensing electrode system is capable of sensing a change to a self capacitance.

25. The illumination device of claim 1, wherein the light guide has light-turning features that are not in electric communication with the touch-sensing electrode system.

26. The illumination device of claim 1, wherein the light guide is disposed over a reflective display.

27. The illumination device of claim 26, wherein the reflective display comprises display elements comprising interferometric modulators.

28. An illumination device with integrated touch-sensor capability comprising:

a guiding means for guiding light having a conducting means for conducting electricity formed on a turning means for turning light; and

a sensing means for sensing a change to a capacitance of the conducting means induced by the proximity of an electrically conductive body.

29. The illumination device of claim 28, wherein the sensing means comprises a touch-sensing electrode system.

30. The illumination device of claim 28, wherein:

the guiding means comprises a light guide;

the conducting means comprises a conductor;

the turning means comprises a light-turning feature;

or

the sensing means comprises a touch-sensing electrode system.

31. A method of manufacturing an illumination device with integrated touch-sensing capability comprising:

disposing a conductor on surfaces of a light-turning feature in a light guide; and

electrically connecting the conductor to an electrode system capable of sensing a change to a capacitance of the conductor induced by the proximity of a electrically conductive body.

32. The method of claim 31, further comprising taper etching the light-turning feature on the light guide to form a facet.

33. The method of claim 32, further comprising depositing a reflective conductor on the facet.

34. The method of claim 33, further comprising depositing an index-matched turning layer on a substrate and taper etching the light-turning feature in the turning layer.

35. The method of claim 34, further comprising:

patterning a first electrode extending in one direction and a second electrode extending in another, non-parallel direction on the substrate before depositing the turning layer;

patterning a gap with two sides in the first electrode formed to prevent the intersection of the first and the second electrodes, the gap breaking the first electrode into a first side and a second side; and

etching the light-turning feature for electrically connecting to one of the first and second sides of the first electrode.

36. The method of manufacturing the illumination device with integrated touch-sensing capability of claim 35, further comprising

forming a conductor on the light-turning feature;

depositing a conductive bridge in a layer over the turning layer, thereby electrically bridging the first and the second side of the first electrode through the conductor formed on the light-turning feature and the conductive bridge.

37. The method of manufacturing the illumination device with integrated touch-sensing capability of claim 34, further comprising

patterning a first electrode extending in one direction and a second electrode extending in another, non-parallel direction on the turning layer;

patterning a gap with two sides in the first electrode formed to prevent the intersection of the first and the second electrodes, the gap breaking the first electrode into a first side and a second side; and

etching the light-turning feature for electrically connecting to one of the first and second sides of the first electrode.

38. The method of manufacturing the illumination device with integrated touch-sensing capability of claim 37, further comprising

forming a conductor on the light-turning feature;

and

depositing a conductive bridge in a layer below the turning layer thereby electrically bridging the first and the second side of the first electrode through the conductor formed on the light-turning feature and the conductive bridge.

39. An illumination device comprising:

a light guide having a conductor formed on a light-turning facet,

wherein the conductor formed on the light-turning facet is electrically connected to an electronic system.

40. The illumination device of claim 39, wherein the electronic system is capable of detecting the proximity of an electrically conductive body.

41. The illumination device of claim 40, wherein the conductor forms electrodes in a capacitive touch sensor system.

42. The illumination device of claim 39, wherein the conductor constitutes a layer in a stack of materials forming an interferometric structure for reducing reflections.

43. The illumination device of claim 39, wherein the conductor extends across an entire display surface.