UV laser based stand-off acoustic sensor

Patent metadata

Field	Value
Publication number	US-10222253-B2
Application number	US-201615175423-A
Country	US
Kind code	B2
Filing date	Jun 7, 2016
Priority date	Jul 14, 2015
Publication date	Mar 5, 2019
Grant date	Mar 5, 2019

Abstract

A system for aerially surveying an area where a plane may have crashed in water and locating pings from the plane's black box using a laser on an aerial platform that produces laser pulses; using a launch telescope to direct the laser pulses to the water producing scattering from the laser pulses and a continuous stream of backscatter; using a receiving telescope to collect the continuous stream of backscatter; using an interferometer operatively connected to the receiving telescope to produce two outputs, wherein one output is the continuous stream of backscatter, and wherein the other output is a delayed replica of the first output; and using a data collection and analysis unit operatively connected to the interferometer to produce a measurement of the sound.

First claim

The invention claimed is:

1. An apparatus for detecting sound in an environment at long distances, comprising:
a platform;
a laser operatively connected to said platform that produces laser pulses;
a launch telescope operatively connected to said laser that directs said laser pulses to the environment producing scattering from said laser pulses and a continuous stream of backscatter;
a receiving telescope operatively connected to said platform that collects said continuous stream of backscatter wherein said continuous stream of backscatter incudes a return pulse and delayed return pulse;
an interferometer operatively connected to said receiving telescope the receives said return pulse and said delayed return pulse, interferes said delayed return pulse with said return pulse, and produces an output; and
a data collection and analysis unit operatively connected to said interferometer that receives said output and provides a measurement of the sound in the environment.

2. The apparatus for detecting sound at long distances of claim 1 wherein said platform is an aerial platform.

3. The apparatus for detecting sound at long distances of claim 1 wherein said platform is a fixed platform.

4. The apparatus for detecting sound at long distances of claim 1 wherein said environment is water.

5. The apparatus for detecting sound at long distances, of claim 1 wherein said environment is an entity producing sound in air.

6. The apparatus for detecting sound at long distances of claim 1 wherein said environment is an individual producing sound in air.

7. The apparatus for detecting sound at long distances of claim 1 wherein said laser is a UV laser.

8. The apparatus for detecting sound at long distances of claim 1 wherein said laser is a UV laser that produces UV laser pulses.

9. The apparatus for detecting sound at long distances of claim 1 wherein said laser is a UV laser that produces nanosecond UV laser pulses.

10. The apparatus for detecting sound at long distances of claim 1 wherein said laser pulses produce Raleigh scattering.

11. The apparatus for detecting sound at long distances of claim 1 wherein said laser pulses produce coherent backscatter.

12. The apparatus for detecting sound at long distances of claim 1 wherein said interferometer is a delayed self-homodyne interferometer.

13. The apparatus for detecting sound at long distances of claim 1 further comprising a system for directing sound into the environment.

14. The apparatus for detecting sound at long distances of claim 1 further comprising a system for directing sound into a water environment.

15. The apparatus for detecting sound at long distances of claim 1 further comprising a laser system for directing sound into a water environment.

16. The apparatus for detecting sound at long distances of claim 1 further comprising a deployable sound generator system for directing sound into a water environment.

17. An apparatus for detecting sound in water at long distances, comprising:
an aerial platform;
a UV laser operatively connected to said areal platform that produces a nanosecond UV laser pulse;
launch telescope operatively connected to said UV laser that directs said nanosecond UV laser pulse to said water producing Raleigh scattering from said nanosecond UV laser pulse and a continuous stream of coherent backscatter;
a receiving telescope operatively connected to said areal platform that collects said continuous stream of coherent backscatter;
a delayed self-homodyne interferometer operatively connected to said receiving telescope that produces two outputs, wherein one output is a portion of said continuous stream of coherent backscatter, and wherein the other output is a delayed portion of said continuous stream of coherent backscatter; and
a data collection and analysis unit operatively connected to said delayed self-homodyne interferometer that produces an output of the detection of the sound in water.

18. A method of detecting sound in an environment at long distances, comprising the steps of:
directing laser pulses from a platform into the environment producing scattering from said laser pulses and a continuous stream of backscatter;
receiving said continuous stream of backscatter that includes a return pulse and delayed return pulse;
interfering said delayed return pulse with said return pulse and producing an output; and
analyzing said output for detecting the sound in the environment.

19. The method of detecting sound at long distances of claim 18 wherein said platform is an aerial platform.

20. The method of detecting sound at long distances of claim 18 wherein said platform is a fixed platform.

21. The method of detecting sound at long distances of claim 18 wherein said environment is water.

22. The method of detecting sound at long distances of claim 18 wherein said environment is an entity producing sound in air.

23. The method of detecting sound in water at long distances of claim 18 wherein said laser is a UV laser.

24. The method of detecting sound in water at long distances of claim 18 wherein said laser is a UV laser that produces UV laser pulses.

Assignees

• L Livermore Nat Security Llc

Inventors

• Dawson Jay W
• Allen Graham S
• Carter Michael R
• Heebner John E
• Messerly Michael J
• Pax Paul H
• Rubenchik Alexander M

Classifications

• G01H9/00 Primary

  Measuring mechanical vibrations or ultrasonic, sonic or infrasonic waves by using radiation-sensitive means, e.g. optical means · CPC title