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 plurality of light-turning features defined by recesses in a surface of the light guide;
a plurality of spaced-apart conductors including a reflective metallic layer, each of the plurality of spaced-apart conductors extending in a corresponding one of the recesses; and
touch-sensing electronics capable of sensing a change to an electric field of a conductor of the plurality of conductors.
2. The illumination device of claim 1 , wherein each of the plurality of spaced-apart conductors resides on a same level as others of the plurality of spaced-apart conductors.
3. The illumination device of claim 1 , wherein the recesses extend partially through the light guide.
4. The illumination device of claim 1 , wherein surfaces of the recesses include facets, wherein the conductors reside on the facets.
5. The illumination device of claim 1 , wherein each of the conductors is coated with a reflection reducing structure to reduce reflections of ambient light from the corresponding conductor.
6. The illumination device of claim 5 , wherein the reflection reducing structure is an interferometric structure, wherein the interferometric structure includes a corresponding one of the plurality of conductors, a spacer layer, and an absorber layer.
7. The illumination device of claim 6 , wherein the interferometric structure is configured to be more reflective of light striking the corresponding conductor than light striking the absorber layer.
8. The illumination device of claim 1 , wherein:
the light guide includes a light-turning layer on a substrate; and
the plurality of light-turning features extend in the light-turning layer.
9. The illumination device of claim 1 , wherein the touch-sensing electronics is capable of determining a location in an x-y plane of the change to the electric field of each one of the plurality of conductors.
10. The illumination device of claim 1 , wherein the touch-sensing electronics is capable of sensing a change to a mutual capacitance.
11. The illumination device of claim 1 , wherein the touch-sensing electronics is capable of sensing a change to a self capacitance.
12. The illumination device of claim 1 , wherein the change to the electric field is induced by the proximity of an electrically conductive body.
13. The illumination device of claim 1 , wherein the light guide is over a reflective display.
14. The illumination device of claim 13 , wherein the reflective display includes display elements including interferometric modulators.
15. The illumination device of claim 1 , further comprising:
a display which can be illuminated by the light guide;
a processor configured to communicate with the display, the processor being configured to process image data; and
a memory device configured to communicate with the processor.
16. The illumination device of claim 15 , wherein the display is rearward of the light guide.
17. The illumination device of claim 15 , further comprising:
a driver circuit configured to send at least one signal to the display; and
a controller configured to send at least a portion of the image data to the driver circuit.
18. The illumination device of claim 15 , further comprising:
an image source module configured to send the image data to the processor, wherein the image source module includes at least one of a receiver, transceiver, and transmitter.
19. The illumination device of claim 15 , further comprising:
an input device configured to receive input data and to communicate the input data to the processor.
20. A method of manufacturing an illumination device with integrated touch-sensing capability, comprising:
providing a light guide having a plurality of light-turning features defined by recesses in a surface of the light guide;
depositing a plurality of spaced-apart conductors, each including a reflective metallic layer on surfaces of a corresponding light-turning feature in the light guide; and
electrically connecting the conductors to touch-sensing electronics capable of sensing a change to an electric field of a conductor of the plurality of conductors.
21. The method of claim 20 , wherein depositing a plurality of spaced-apart conductors includes depositing each of the plurality of spaced-apart conductors on a same level.
22. The method of claim 20 , wherein the recesses extend partially through the light guide.
23. The method of claim 20 , wherein providing the light guide includes taper etching each of the light-turning features on the light guide to form facets.
24. The method of claim 20 , wherein providing the light guide includes depositing an index-matched turning layer on a substrate and taper etching the light-turning features in the turning layer.
25. The method of claim 20 , further comprising providing a display adjacent the light guide such that the light guide is configured to illuminate the display.
26. The method of claim 25 , wherein the plurality of light-turning features are forward of the display and configured to direct light rearwards toward the display.