Free-space optically accessed acoustically modulated retro-reflector arrays

1. A system comprising:

a plurality of acousto-optic retro reflectors, wherein each of the acousto-optic retro reflectors is configured to physically react in response to an acoustic signal;

a light scanner configured to sequentially transmit a first light signal towards each individual acousto-optic retro reflector in the plurality of acousto-optic retro reflectors;

a light detector configured to receive a second light signal emitted by the light scanner, wherein the second light signal is reflected by the plurality of acousto-optic retro reflectors; and

a processor configured to determine at least one property of the acoustic signal based upon the second light signal received by the light detector.

2. The system of claim 1 , wherein the plurality of acousto-optic retro reflectors are arranged as a one dimensional array.

3. The system of claim 1 , wherein the plurality of acousto-optic retro reflectors are arranged as a multi-dimensional array.

4. The system of claim 1 , wherein the plurality of acousto-optic retro reflectors are arranged as an end-fire array.

5. The system of claim 1 , wherein the plurality of acousto-optic retro reflectors are arranged as a broadside array.

6. The system of claim 1 , wherein the first light signal is a laser light.

7. The system of claim 6 , wherein the laser light is emitted from a device in a group consisting of a gas laser, a chemical laser, an excimer laser, a solid-state laser, a fiber laser, a photonic crystal laser, a semiconductor laser, a dye laser, a free electron laser, and a bio laser.

8. The system of claim 1 , wherein the plurality of acousto-optic retro reflectors are passive.

9. The system of claim 1 , wherein the determining at least one property of the acoustic signal comprises detecting an acoustic signal source location.

10. The system of claim 1 , wherein the determining at least one property of the acoustic signal comprises reconstructing the acoustic signal.

11. The system of claim 1 , wherein the light scanner is further configured to transmit a light signal towards, and receive a light signal from, an additional acousto-optic retro reflector based on the determining at least one property of the acoustic signal.

12. The system of claim 1 , wherein the light scanner is further configured to cease transmitting light towards, and receiving light from, a spare acousto-optic retro reflector based on the determining at least one property of the acoustic signal.

13. The system of claim 1 , wherein the light scanner and the light detector are a single unit.

14. The system of claim 1 , wherein the second light signal reflected by the plurality of acousto-optic retro reflectors is an acoustically modulated form of the first light signal emitted by the light scanner.

15. The system of claim 1 , wherein the sequence is predetermined.

16. The system of claim 15 , wherein the processor is further configured to determine at least one property of the acoustic signal based at least on the location of the plurality of acousto-optic retro reflectors and the predetermined sequence.

17. The system of claim 1 , wherein the sequence is a continuous scan.

18. The system of claim 17 , further configured to:

establish an array topology based on the second light signal received as a result of the continuous scan; and

determine at least one property of the acoustic signal based on array topology.

19. The system of claim 1 , wherein the sequence is determined dynamically.

20. The system of claim 19 , further configured to determine a sequence based on the light detector successfully receiving an acoustically modulated light signal from one or more of the plurality of acousto-optic retro reflectors, wherein the sequence incorporates at least the acousto-optic retro reflectors from which the light detector successfully received an acoustically modulated light signal.

21. The system of claim 20 , further configured to:

establish an array topology based on the location of the acousto-optic retro reflectors from which the light detector successfully received an acoustically modulated light signal; and

determine at least one property of the acoustic signal based on array topology.

22. The system of claim 1 , further configured to:

determine an array topology based on the plurality of acousto-optic retro reflectors; and

determine at least one property of the acoustic signal based on the array topology.

23. The system of claim 1 , wherein the light source is separated from the plurality of acousto-optic retro reflectors by free-space.

24. The system of claim 1 , wherein the light detector is separated from the plurality of acousto-optic retro reflectors by free-space.

25. The system of claim 1 , wherein the light scanner is configured to transmit the first light signal independent of the second light signal.

26. The system of claim 1 , wherein the light sensor is placed within a line of sight of the plurality of acousto-optic retro reflectors.

27. The system of claim 1 , wherein an acousto-optic retro reflector in the plurality of acousto-optic retro reflectors is selected from the group consisting of a corner cube reflector and a spherical reflector.

28. A method, comprising:

sequentially transmitting a light signal towards each individual acousto-optic retro reflector in a plurality of acousto-optic retro reflectors, wherein the plurality of acousto-optic retro reflectors is configured to physically react to an acoustic signal;

receiving a modulated form of at least one transmitted light signal resulting from the physical reaction of at least one corresponding reflector of the plurality of acousto-optic retro reflectors; and

determining at least one property of the acoustic signal based upon the modulated form of the at least one transmitted light signal.

29. The method of claim 28 , wherein the plurality of acousto-optic retro reflectors is arranged as a one dimensional array.

30. The method of claim 28 , wherein the plurality of acousto-optic retro reflectors is arranged as a multi-dimensional array.

31. The method of claim 28 , wherein the plurality of acousto-optic retro reflectors is arranged as an end-fire array.

32. The method of claim 28 , wherein the plurality of acousto-optic retro reflectors is arranged as a broadside array.

33. The method of claim 28 , wherein the plurality of acousto-optic retro reflectors is passive.

34. The method of claim 28 , wherein the determining at least one property of the received modulated form of the transmitted light signal comprises detecting an acoustic signal source location.

35. The method of claim 28 , wherein the determining at least one property of the received modulated form of the transmitted light signal comprises reconstructing the acoustic signal.

36. The method of claim 28 , wherein the light scanner and the light detector are a single unit.