Optical spot displacement apparatus

• US 20060044987A1
• Filed: 07/15/2005
• Published: 03/02/2006
• Est. Priority Date: 07/16/2004
• Status: Active Grant

• Current Assignee: Ohio State University
• Original Assignee: Ohio State University
• Inventors: Anderson, Betty Lise, Argueta-Diaz, Victor
• Granted Patent: US 7,660,499 B2
• Time in Patent Office: Days
• US Class Current: 369/112.10
• CPC Class Codes: G02B 19/0023 at least one surface having optical power
• CPC Class Codes: G02B 19/0033 characterised by the use
• CPC Class Codes: G02B 26/0833 the reflecting element being a micromechanical device, e.g. a MEMS mirror, DMD G02B26/0825 takes precedence; micromechanical devices in general B81B
• CPC Class Codes: G02B 6/0018 Redirecting means on the surface of the light guide
• CPC Class Codes: G02B 6/0068 Arrangements of plural sources, e.g. multi-colour light sources

Abstract

Optical spot displacement apparatus comprises: a face that is divided into a plurality of columns; each column of the plurality including a predetermined number of prisms, the predetermined number of prisms of a same column configured within the corresponding column to displace at least one incident light beam a common predetermined distance from incidence, and the predetermined number of prisms of different columns configured within each corresponding column to displace the at least one incident light beam a different predetermined distance from incidence.

Claims

1. Optical spot displacement apparatus comprising:

a face, said face being divided into a plurality of columns;

each column of said plurality including a predetermined number of prisms, said predetermined number of prisms of a same column configured within the corresponding column to displace at least one incident light beam a common predetermined distance from incidence, and said predetermined number of prisms of different columns configured within each corresponding column to displace said at least one incident light beam a different predetermined distance from incidence.

2. The apparatus of claim 1 wherein the prisms of each column comprise roof prisms;

wherein each roof prism comprising an entrance for accepting at least one light beam incident thereon and an exit for exiting said at least one incident light beam therefrom; and

wherein each roof prism of the same column configured within the corresponding column to displace the at least one incident light beam a common predetermined distance from prism entrance to prism exit, and each roof prism of different columns configured within each corresponding column to displace the at least one incident light beam a different predetermined distance from prism entrance to prism exit.

3. The apparatus of claim 2 wherein each roof prism including a base and at least two sides for internal reflection of light, the base of each said predetermined number of prisms of each column disposed at said face for accepting at least one incident light beam at the entrance, for internally reflecting the at least one incident light beam, and for exiting the reflected at least one light beam the predetermined distance from the entrance.

4. The apparatus of claim 2 including at least one lens disposed at the entrance of each prism for reducing divergence of the at least one incident light beam;

and at least one lens disposed at the exit of each prism for restoring any divergence of an exiting at least one light beam.

5. The apparatus of claim 2 wherein the predetermined number of prisms of different columns increase from column to column according to a binary sequence.

6. The apparatus of claim 1 wherein the prisms of some columns of the plurality comprise at least one pair of input and output prisms that are spaced apart along an optical path of the corresponding column a distance commensurate with the predetermined displacement distance of the at least one light beam, each input prism of said pair for directing the at least one incident light beam along said optical path to said output prism, and each output prism for receiving and exiting the at least light beam directed thereto.

7. The apparatus of claim 1 wherein the prisms of some columns of the plurality are joined together in sets so that the at least one incident light beam may travel inside each set of joined prisms;

and wherein the number of prisms in each set for each of said some columns is commensurate with the predetermined displacement distance of the corresponding column of said set.

8. The apparatus of claim 7 wherein each prism of the some columns includes a base with an input light region and an output light region;

and wherein the prisms are joined together at their bases output light region to input light region to form each set.

9. The apparatus of claim 7 including at least one lens disposed within each set of joined prisms for reducing beam divergence of the at least one light beam traveling the set.

10. The apparatus of claim 1 wherein the predetermined displacement distance of each column increases from column to column according to a binary sequence.

11. The apparatus of claim 1 including an input/output plane for the at least one incident light beam;

and at least one input lens disposed at a predetermined distance from said input/output plane for reducing divergence of the at least one incident light beam.

12. The apparatus of claim 11 including at least one output lens disposed at a predetermined distance from said input/output plane for reducing divergence of the at least one displaced light beam.

13. Optical spot displacement apparatus comprising:

a first plane and a second plane;

a mirror disposed at said first plane, said mirror including an entrance region and an exit region;

a series of spherical mirrors disposed along a path at said second plane;

wherein at least one light beam incident the entrance region will enter and travel along said path by reflections between the spherical mirrors of said second plane and mirror of said first plane until said at least one light beam reaches the exit region where it exits rendering the at least one light beam displaced by a predetermined distance commensurate with a distance between the entrance and exit regions of said mirror.

14. The apparatus of claim 13 wherein the first and second planes are upper and lower planes, respectively, of an optical waveguide section.

15. The apparatus of claim 13 wherein each spherical mirror has a focal length;

and wherein a distance between the first and second plane is less than substantially four times the focal length.

16. The apparatus of claim 13 including an input optical element disposed at the entrance region for coupling the at least one incident light beam at a predetermined angle through the first plane to one of the spherical mirrors of the series.

17. The apparatus of claim 16 wherein the input optical element comprises a prism.

18. The apparatus of claim 13 including an output optical element disposed at the exit region for coupling the traveling at least one light beam at a predetermined angle to exit through the first plane.

19. The apparatus of claim 18 wherein the output optical element comprises a prism.

20. Optical waveguide based spot displacement apparatus comprising:

a substrate of a first refractive index;

a core channel of a second refractive index disposed within said substrate, said second refractive index being greater than the first refractive index, said core channel including an entrance region and an exit region spaced apart a predetermined distance;

a first optical element disposed at said entrance region for coupling at least one incident light beam into said core channel at a first predetermined angle to cause said at least one incident light beam to travel through said core channel; and

a second optical element disposed at said exit region for coupling said at least one traveling light beam from said core channel at a second predetermined angle to cause said at least one traveling light beam to exit from said core channel.

21. The apparatus of claim 20 wherein the first optical element and second optical elements both have a third refractive index that is greater then the second refractive index.

22. The apparatus of claim 20 wherein the first optical element comprises a first prism disposed above the entrance region of the core channel a first predetermined distance for refracting the at least one incident light beam at the first predetermined angle;

and wherein the second optical element comprises a second prism disposed above the exit region of the core channel a second predetermined distance for refracting the at least one traveling light beam at the second predetermined angle.

23. The apparatus of claim 22 wherein air separates the first and second prisms from their respective entrance and exit regions of the core channel;

and wherein the refractive index of air is less than both of the first and second refractive indices.

24. The apparatus of claim 20 wherein the first optical element comprises a first diffraction grating disposed at the entrance region of the core channel for diffracting the at least one incident light beam at the first predetermined angle;

and wherein the second optical element comprises a second diffraction grating disposed at the exit region of the core channel for diffracting the at least one traveling light beam at the second predetermined angle.

25. The apparatus of claim 24 wherein the first and second diffraction gratings are etched into their respective entrance and exit regions of the core channel.

26. The apparatus of claim 24 wherein the first and second angles of defraction are controlled in accordance with grating periods of their respective first and second diffraction gratings.

27. The apparatus of claim 26 wherein the grating periods of the first and second diffraction gratings are set to permit a ninety degree matching coupling to their respective incident and traveling at least one light beam.

28. Optical spot displacement apparatus comprising:

a face, said face being divided into a plurality of columns;

each column of said plurality including a predetermined number of waveguide based light beam displacement sections, said predetermined number of waveguide based light beam displacement sections of a same column configured within the corresponding column to displace at least one incident light beam a common predetermined distance from incidence, and said predetermined number of waveguide based light beam displacement sections of different columns configured within each corresponding column to displace said at least one incident light beam a different predetermined distance from incidence.

29. The apparatus of claim 28 wherein each waveguide based light beam displacement section comprising:

a substrate of a first refractive index;

a core channel of a second refractive index disposed within said substrate, said second refractive index being greater than the first refractive index, said core channel including an entrance region and an exit region spaced apart a predetermined distance;

a first optical element disposed at said entrance region for coupling at least one incident light beam into said core channel at a first predetermined angle to cause said at least one incident light beam to travel through said core channel; and

a second optical element disposed at said exit region for coupling at least one traveling light beam from said core channel at a second predetermined angle to cause said at least one traveling light beam to exit from said core channel, wherein the light beam displacement distance of each section being commensurate with the predetermined distance separating the exit region from the entrance region.

30. The apparatus of claim 29 wherein the first optical element comprises a first diffraction grating disposed at the entrance region of the core channel for diffracting the at least one incident light beam at the first predetermined angle;

and wherein the second optical element comprises a second diffraction grating disposed at the exit region of the core channel for diffracting the at least one traveling light beam at the second predetermined angle.

31. The apparatus of claim 30 wherein the first and second diffraction gratings are etched into their respective entrance and exit regions of the core channel.

32. The apparatus of claim 28 wherein the predetermined number of waveguide based light beam displacement sections of different columns increase from column to column according to a binary sequence.

33. The apparatus of claim 28 wherein the predetermined displacement distance of the waveguide based light beam displacement sections of each column increases from column to column according to a binary sequence.