Illumination device with metalized light-turning features
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.
1. An illumination device with integrated touch-sensing capability comprising:
a light guide having a conductor formed on a light-turning feature, and extending into a recess of the light turning feature; and
a touch-sensing electrode system capable of sensing a change to an electric field of the conductor,
wherein the touch-sensing electrode s stem includes a first electrode extending in one direction and a second electrode extending in another, non-parallel direction,
wherein 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
wherein the first and second electrodes are formed on a single surface.
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 the electric field of the conductor.
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 the display, the processor being configured to process image data; and
a memory device that is configured to communicate with the processor.
8. The illumination device of claim 7 , further comprising a driver circuit configured to send at least one signal to the display.
9. The illumination device of claim 8 , further comprising a controller configured to send at least a portion of the image data to the driver circuit.
10. The illumination device of claim 7 , further comprising an image source module configured to send the image data to the processor.
11. The illumination device of claim 10 , wherein the image source module includes at least one of a receiver, transceiver, or transmitter.
12. The illumination device of claim 7 , further comprising:
an input device configured to receive input data and to communicate the input data to the processor.
13. The illumination device of claim 1 , wherein
the light guide includes 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 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.
15. The illumination device of claim 14 , wherein the first and second electrodes include transparent conductors.
16. The illumination device of claim 14 , wherein the conductive bridge is formed on a level below the surface of the first and second electrodes.
17. The illumination device of claim 14 , wherein the conductive bridge includes a reflective conductor.
18. The illumination device of claim 14 , wherein the vias include a reflective conductor.
19. The illumination device of claim 18 , wherein the vias are light-turning features configured to direct light downward out of the light guide.
20. The illumination device of claim 1 , wherein the first and second electrodes are formed in two different layers.
21. The illumination device of claim 1 , wherein the touch-sensing electrode system is capable of sensing a change to a mutual capacitance.
22. The illumination device of claim 1 , wherein the touch-sensing electrode system is capable of sensing a change to a self capacitance.
23. The illumination device of claim 1 , wherein the light guide has light-turning features that are not in electrical communication with the touch-sensing electrode system.
24. The illumination device of claim 1 , wherein the light guide is disposed over a reflective display.
25. The illumination device of claim 24 , wherein the reflective display includes display elements including interferometric modulators.
26. The illumination device of claim 1 , wherein the change to the electric field is induced by the proximity of a body.
27. The illumination device of claim 26 , wherein the body is electrically conductive.
28. A method of manufacturing an illumination device with integrated touch-sensing capability comprising:
patterning a first electrode extending in one direction and a second electrode extending in another, non-parallel direction on a substrate;
patterning a gap with two sides in the first electrode formed to prevent the intersection of the first and second electrodes, the gap breaking the first electrode into a first side and a second side;
depositing an index-matched turning layer on the substrate to form a light guide;
taper etching a light-turning feature in the turning layer to form a facet;
depositing a reflective conductor on surfaces of the facet, and extending into a recess of the facet;
etching the light-turning feature for electrically connecting to one of the first and second sides of the first electrode; and
electrically connecting the conductor to an electrode system capable of sensing a change to an electric field of the conductor, the electrode system including the first and second electrodes.
29. The method of manufacturing the illumination device with integrated touch-sensing capability of Claim 28 , further comprising
depositing a conductive bridge in a layer over the turning layer, thereby electrically bridging the first side and the second side of the first electrode through the conductor formed on the light-turning feature and the conductive bridge.
30. The method of claim 28 , wherein the change to the electric field is induced by the proximity of a body.
31. The method of claim 30 , wherein the body is electrically conductive.
32. The method of claim 28 , wherein sensing the change to the electric field includes sensing a change to a capacitance of the conductor.
33. A method of manufacturing the an illumination device with integrated touch-sensing capability comprising:
depositing an index-matched turning layer on a substrate;
taper etching the light-turning feature in the turning layer to form a facet;
depositing a reflective conductor on surfaces of the facet, and extending into a recess of the facet;
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;
etching the light-turning feature for electrically connecting to one of the first and second sides of the first electrode; and
electrically connecting the conductor to an electrode system capable of sensing a change to an electric field of the conductor, the electrode system including the first and second electrodes.
34. The method of manufacturing the illumination device with integrated touch-sensing capability of claim 33 , further comprising
depositing a conductive bridge in a layer below the turning layer thereby electrically bridging the first side and the second side of the first electrode through the conductor formed on the light-turning feature and the conductive bridge.
35. An illumination device comprising:
a light guide having a conductor, formed on a light-turning facet, and extending into a recess of a light turning feature,
a first electrode extending in one direction and a second electrode extending in another, non-parallel direction,
wherein the first electrode has a gap with two sides formed to prevent the intersection of the first and second electrodes, the gap breaking the first electrode into a first side and a second side,
wherein the first and second electrodes are formed on a single surface, and
wherein the conductor formed on the light-turning facet is electrically connected to an electronic system.
36. The illumination device of claim 35 , wherein the electronic system is capable of detecting the proximity of an electrically conductive body.
37. The illumination device of claim 36 , wherein the conductor forms electrodes in a capacitive touch sensor system.
38. The illumination device of claim 35 , wherein the conductor constitutes a layer in a stack of materials forming an interferometric structure for reducing reflections.
39. The illumination device of claim 35 , wherein the conductor extends across an entire display surface.