Apparatus and method for a molded waveguide for use with touch screen displays

• US 7,471,865 B2
• Filed: 06/04/2004
• Issued: 12/30/2008
• Est. Priority Date: 06/04/2004
• Status: Expired due to Fees

• Current Assignee: POA Sana Liquidating Trust
• Original Assignee: POA Sana Liquidating Trust
• Inventors: Graham, David S.
• Primary Examiner(s): Font; Frank G
• Assistant Examiner(s): CHIEM, DINH D
• Application Number:
  US10/861,251
• Publication Number:
  US 20050271319A1
• Time in Patent Office: 1,670 Days
• Field of Search: None
• US Class Current: 385/132
• CPC Class Codes: G02B 6/124 Geodesic lenses or integrated gratings
• CPC Class Codes: G02B 6/138 by using polymerisation
• CPC Class Codes: G02B 6/32 having lens focusing means positioned between opposed fibre ends with lens being an integral part of the single fibre end G02B6/262
• CPC Class Codes: G02B 6/43 Arrangements comprising a plurality of opto-electronic elements and associated optical interconnections
• CPC Class Codes: G06F 3/0421 by interrupting or reflecting a light beam, e.g. optical touch-screen
• CPC Class Codes: Y10T 29/49117 Conductor or circuit manufacturing

Abstract

An apparatus and method for an inexpensive, simple to make, self-aligning molded waveguide made of an optically transparent material and that can be used to generate a grid or lamina of light for use with touch screen displays. The molded waveguide substrate includes a plurality of lenses and a plurality of waveguide grooves corresponding to the plurality of integral lenses respectively. After the substrate is molded, the grooves are filled with an optically transparent material to optically couple and align the plurality of lenses and the plurality of grooves respectively. In one application, the molded waveguide substrate is positioned adjacent a touch screen device. A light transmitter and an imaging device are optically coupled to the molded waveguide substrate, and a processing device is coupled to the imaging device. The processing device is configured to determine a data entry to the touch screen by deciphering the coordinates of an interrupt in the light created in the free space adjacent the touch screen device when a data entry is being made to the touch screen device.

Claims

1. An apparatus, comprising:

a molded substrate body made from a first optically transparent material having;

(i) a plurality of integrally molded optical lenses shaped as part of the molded substrate body and made from the first optically transparent material having backside surface and a curved optical face on the side of the lens opposite from the backside surface; and

(ii) a plurality of negative grooves molded into the substrate body wherein the grooves terminate at the backside surface of the integrally molded optical lenses and in optical alignment with the plurality of integral lenses,

the molded substrate body, the plurality of integral optical lenses, and the plurality of negative grooves form a monolithic waveguide substrate; and

a second optically transparent material provided within the plurality of negative waveguide grooves, the optically transparent material forming a plurality of waveguide cores that terminate at the backside surface of the integrally molded optical lenses such that the cores are in contact with and in optical alignment with the plurality of integral optical lenses,

each of the plurality of integrally molded optical lenses are molded to taper toward the backside surface of said lens and taper toward an associated one of the plurality of negative grooves so as to contact an associated waveguide core.

2. The apparatus of claim 1, wherein the plurality of integral optical lenses are three-dimensional lenses.

3. The apparatus of claim 1, wherein the plurality of integral optical lenses have a dimension ranging from 50 to 2000 microns in diameter.

4. The apparatus of claim 1, wherein the plurality of waveguide grooves are approximately 5 to 50 microns deep.

5. The apparatus of claim 1, wherein the plurality of waveguide grooves are approximately 3 to 50 microns wide.

6. The apparatus of claim 1, wherein the monolithic waveguide substrate and the plurality of integral optical lenses have an index of refraction ranging from n=1.0 to 2.0.

7. The apparatus of claim 1, wherein the monolithic waveguide substrate and the plurality of integral optical lenses are made from a the first optically transparent material having a first index of refraction and the plurality of grooves are filled with the second optically transparent material having a second index of refraction, wherein the second index of refraction is greater than the first index of refraction.

8. The apparatus of claim 1, wherein the plurality of optical lenses are configured with optical properties to create a lamina of light when light is provided to inputs of the plurality of waveguides grooves.

9. The apparatus of claim 1, wherein the plurality of integral optical lenses are configured with optical properties to create a grid of light when light is provided to inputs of the plurality of waveguides grooves.

10. The apparatus of claim 1, wherein the monolithic waveguide substrate is further configured with a first sub-set of the plurality of waveguide grooves extending in a first direction along a first axis.

11. The apparatus of claim 10, wherein the monolithic waveguide substrate is further configured with a second sub-set of the plurality of waveguide grooves extending in a second direction along a second axis.

12. The apparatus of claim 11, wherein the first axis and the second axis are either perpendicular or parallel to each other.

13. The apparatus of claim 1, wherein the monolithic waveguide substrate is further configured such that the plurality of waveguide grooves extend on a first surface of the monolithic substrate and a second surface of the monolithic substrate, wherein the first surface and the second surface are perpendicular to one another.

14. The apparatus of claim 1, wherein a first sub-set of the plurality of waveguide grooves are configured to be optically coupled to a light emitter.

15. The apparatus of claim 1, wherein a first sub-set of the plurality of grooves are configured to be optically coupled to an imaging device.

16. The apparatus of claim 1, wherein the monolithic waveguide substrate is shaped into one the following shapes:

a straight substrate;

a square;

an L-shaped member, a rectangle, triangle, round, or oval.

17. The apparatus of claim 1, further comprising:

a touch screen device, the monolithic waveguide substrate being configured to create light in the free space adjacent the touch screen device; and

an imaging device optically coupled to the light created in the free space adjacent the touch screen device.

18. The apparatus of claim 17, further comprising a processing device coupled to the imaging device, the processing device configured to determine a data entry to the touch screen by deciphering the coordinates of an interrupt in the light created in the free space adjacent the touch screen device when a data entry is being made to the touch screen device.

19. The apparatus of claim 1, wherein the monolithic waveguide substrate is formed by one of the following:

injection molding;

compression molding;

embossing;

or optical micro-molding.

20. The apparatus of claim 1, wherein the integral optical lenses comprise the following optical elements:

gratings, bragg gratings, coupling horns.

21. The apparatus of claim 1, wherein the plurality of negative waveguide grooves have angled walls.

22. The apparatus of claim 1, wherein the angled walls ranges from 3 to 5 degrees.

23. The apparatus of claim 1, wherein the plurality of negative waveguide grooves are approximately 6 to 8 microns wide and 20 to 25 microns deep.

24. The apparatus of claim 1, wherein the plurality of integral optical lenses have a height ranging from 40 to 250 microns.

25. The apparatus of claim 1, wherein the monolithic waveguide substrate is made from a polycarbonate material.

26. The apparatus of claim 1, wherein the plurality of integral optical lenses have a diameter ranging from 750 microns to 1 millimeter.

27. The apparatus of claim 1, wherein the first optically transparent material forming the monolithic waveguide substrate is made from a light curable material.

28. The apparatus of claim 27, wherein the light curable material comprises an epoxy or urethane.

29. The apparatus of claim 1, wherein the second optically transparent material is a UV curable material.

30. The apparatus of claim 1, wherein the second optically transparent material consists of an optical adhesive urethane or an optical epoxy.

31. The apparatus of claim 1, wherein each of the molded optical lenses that form part of the substrate body comprising the first optically transparent material are self-aligned with each associated waveguide core comprising the second optically transparent material.

32. The apparatus of claim 1, wherein the substrate body has a top planar portion of the surface and wherein the negative grooves are recessed into the substrate body such that the waveguide cores are formed below the top planar portion of the surface and wherein the curved optical faces of the each of the molded optical lenses are oriented so that a portion of the curved optical surface is above said top planar portion and another portion of the curved optical surface is below said top planar portion.

33. The apparatus of claim 1, wherein each of the molded optical lenses comprise a single lens element.

34. The apparatus of claim 32, wherein the plurality of integral optical lenses have a height extending above the top planar portion of the surface, said height ranging from 40 to 250 microns.