Illumination device with metalized light-turning features

• US 9,182,851 B2
• Filed: 08/14/2014
• Issued: 11/10/2015
• Est. Priority Date: 12/29/2009
• Status: Active Grant

• Current Assignee: Snaptrack Incorporated (Qualcomm, Inc.)
• Original Assignee: Qualcomm MEMS Technologies Incorporated (Qualcomm, Inc.)
• Inventors: Bita, Ion, Dhanens, Stephen P., Gousev, Evgeni P., Narayanan, Kollengode S.
• Primary Examiner(s): Bolotin, Dmitriy
• Application Number:
  US14/459,541
• Publication Number:
  US 20140354601A1
• Time in Patent Office: 453 Days
• Field of Search: 345173-179, 178 1801- 1811, 359/290, 349 61- 71, 362615-629
• US Class Current: 1/1
• 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 plurality of light-turning features defined by recesses in a surface of the light guide;

a plurality of spaced-apart conductors, individual ones of the plurality of conductors residing on and extending into a corresponding one of the recesses without extending into an immediately neighboring recess; 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 plurality of conductors includes a reflective metallic layer.

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, further comprising a plurality of mask structures, each mask structure disposed over a corresponding one of the plurality of the conductors and configured to reduce reflections of ambient light from the corresponding conductor.

6. The illumination device of claim 5, wherein the mask structures are interferometric structures.

7. The illumination device of claim 6, wherein the recesses extend into the surface of the light guide towards an opposite surface of the light guide, and wherein the interferometric structures are configured to reflect light propagating within the light guide while providing a lower-level of reflection of ambient light.

8. The illumination device of claim 1, wherein:

the light guide includes a light-turning layer disposed on a substrate; and

the plurality of light-turning features extending 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 disposed 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, 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.

17. 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.

18. 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.

19. 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;

disposing individual ones of a plurality of spaced-apart conductors on surfaces of a corresponding light-turning feature in the light guide, and extending into the corresponding recess of the light-turning feature without extending into an immediately neighboring recess; and

electrically connecting the conductors to touch-sensing electronics capable of sending a change to an electric field of a conductor of the plurality of conductors.

20. The method of claim 19, wherein disposing individual ones of a plurality of spaced-apart conductors on surfaces of a corresponding light-turning feature in the light guide includes forming each of the plurality of spaced-apart conductors on a same level.

21. The method of claim 19, wherein disposing individual ones of a plurality of spaced-apart conductors on surfaces of a corresponding light-turning feature in the light guide includes depositing a reflective metallic layer on the surfaces of the corresponding light-turning feature.

22. The method of claim 19, wherein providing the light guide includes taper etching each of the light-turning features on the light guide to form facets.

23. The method of claim 19, 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.

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

a means for guiding light having a plurality of means for turning light defined by recesses in a surface of the guiding means;

a plurality of spaced-apart means for conducting electricity, individual ones of the conducting means residing on a corresponding turning means, and extending into the recess of the corresponding turning means without extending into an immediately neighboring recess; and

a means for detecting a touch event based on sensing a change to an electric field of a conducting means of the plurality of conducting means.

25. The illumination device of claim 24, wherein the guiding means includes a light guide;

the conducting means includes a conductor;

the turning means includes a light-turning feature;

or the detecting means includes touch-sensing electronics.

26. The illumination device of claim 24, wherein the plurality of spaced-apart conducting means resides on a same level.

27. The illumination device of claim 24, wherein the conducting means includes a reflective metallic conductor.

28. The illumination device of claim 24, wherein the change to the electric field is induced by the proximity of an electrically conductive body.

29. The illumination device of claim 24, wherein the detecting means includes means for sensing a change to a capacitance of the conducting means.