Laser beam control system and method
A laser beam control system includes an output aperture through which a laser beam is directed toward a target. A laser beam return is also received through the output aperture, with the laser beam return including scatter from the laser beam. A deformable mirror is adapted to control the outgoing laser beam, and a sensor is adapted to detect the wavefront of the laser beam return. An optics controller is operationally coupled to the deformable mirror and is adapted to adjust the deformable mirror in response to the wavefront of the laser beam return.
1. A laser beam control system comprising:
an output aperture through which a laser beam is directed toward a target, and through which a laser beam return is received, the laser beam return including scatter from the laser beam;
a deformable mirror adapted to control the laser beam;
a first sensor adapted to detect a wavefront of the scatter from the laser beam in the laser beam return; and
an optics controller operationally coupled to the deformable mirror and adapted to adjust the deformable mirror in response to the wavefront,
wherein the scatter comprises a first scatter resulting from the laser beam incident upon the target superimposed on a second scatter resulting from the laser beam passing through a medium between the output aperture and the target.
2. The system of claim 1 , wherein a signal generated by the first sensor is analyzed by the optics controller to differentiate between the first scatter and the second scatter.
3. The system of claim 2 , wherein the optics controller uses speckle statistics to analyze the signal.
4. The system of claim 1 , wherein the controller is adapted to adjust the deformable mirror in response to a comparison of a wavefront of the first scatter with a wavefront of the second scatter.
5. The system of claim 1 , further comprising scatter control elements disposed along an optical path leading from a source of the laser beam to the output aperture.
6. The system of claim 1 , wherein the deformable mirror performs as a primary mirror.
7. The system of claim 1 , wherein the deformable mirror performs as a fast steering mirror.
8. A laser beam control system comprising:
an output aperture through which a laser beam is directed toward a target, and through which a laser beam return is received, the laser beam return including scatter from the laser beam;
a deformable mirror adapted to control the laser beam;
a first sensor adapted to detect a wavefront of the scatter from the laser beam in the laser beam return;
a second sensor adapted to detect a wavefront of the laser beam before the laser beam is directed through the output aperture; and
an optics controller operationally coupled to the deformable mirror and adapted to adjust the deformable mirror in response to the wavefront of the scatter.
9. The system of claim 8 , wherein the optics controller is adapted to adjust the deformable mirror in response to the wavefronts detected by the first sensor and the second sensor.
10. A laser beam control system comprising:
an output aperture, comprising a quarter wave plate, through which a laser beam is directed toward a target, and through which a laser beam return is received, the laser beam return including scatter from the laser beam;
a deformable mirror adapted to control the laser beam;
a first sensor adapted to detect a wavefront of the scatter from the laser beam in the laser beam return; and
an optics controller operationally coupled to the deformable mirror and adapted to adjust the deformable mirror in response to the wavefront.
11. A laser beam control system comprising:
an output aperture through which a laser beam is directed toward a target, and through which a laser beam return is received, the laser beam return including scatter from the laser beam;
a target illuminator adapted to direct a target illuminator beam toward a target, wherein a target illuminator beam return is generated by scatter of the target illuminator beam off the target and is received through the output aperture;
a steering mirror adapted to direct the laser beam along an optical path toward the output aperture;
a sensor adapted to detect the scatter from the laser beam in the laser beam return; and
an optics controller adapted to steer the laser beam, based upon a relative position of the scatter from the laser beam in the laser beam return on the sensor, by controlling an angular position of the steering mirror.
12. The system of claim 11 , wherein the target illuminator beam and the laser beam have different wavelengths.
13. The system of claim 11 , further comprising a dispersive element adapted to image each of the laser beam return and the target illuminator beam return onto separate areas of the sensor.
14. The system of claim 13 , wherein the optics controller is adapted to steer the laser beam based upon relative positions on the sensor of images generated by the laser beam return and the target illuminator beam return.
15. The system of claim 11 , further comprising scatter control elements disposed along an optical path leading from a source of the laser beam to the output aperture.
16. A laser beam control system comprising:
an output aperture, comprising a quarter wave plate, through which a laser beam is directed toward a target, and through which a laser beam return is received, the laser beam return including scatter from the laser beam;
a steering mirror adapted to direct the laser beam along an optical path toward the output aperture;
a sensor adapted to detect the scatter from the laser beam in the laser beam return; and
an optics controller adapted to steer the laser beam, based upon a relative position of the scatter from the laser beam in the laser beam return on the sensor, by controlling an angular position of the steering mirror.
17. A target tracking system comprising:
a dispersive element optically coupled to an input aperture, wherein the input aperture receives a first laser beam return and a second laser beam return, the laser beam returns being at different wavelengths;
a sensor optically coupled to the dispersive element, wherein the dispersive element is adapted to image the laser beam returns onto the sensor, the first laser beam return generating a first image on a first area of the sensor, and the second laser beam return generating a second image on a second area of the sensor; and
an optics controller operationally coupled to the sensor and adapted to determine a relative spatial relationship between the first and second laser beam returns based upon relative positions of the images generated on the sensor.
18. The system of claim 17 , further comprising a steering mirror operationally coupled to the optics controller, wherein the optics controller is adapted to control an angular position of the steering mirror in response to the determined relative spatial relationship.
19. The system of claim 17 , wherein the optics controller is adapted to generate a virtual image of the second image in the first area of the sensor, such that relative positions of the virtual image and the first image in the first area of the sensor indicates the relative spatial relationship.
20. A laser beam control system comprising:
an output aperture through which a laser beam is directed outward toward a target, the laser beam being directed along an optical path between a laser source and the output aperture, wherein the optical path is defined by at least:
a steering mirror;
a deformable mirror adapted to perform as both a fast steering mirror and as a primary mirror;
a secondary mirror;
a first quarter-wave plate adapted to transmit a first selected polarization of the laser beam; and
a second quarter-wave plate adapted to edge and core and to transmit a second selected polarization of the laser beam.
21. The system of claim 20 , further comprising:
a sensor adapted to detect a wavefront of a laser beam return received through the output aperture; and
an optics controller operationally coupled to the deformable mirror and adapted to adjust the deformable mirror in response to the wavefront detected by the sensor.
22. The system of claim 21 , wherein a signal generated by the sensor resulting from detection of the wavefront is analyzed by the optics controller using speckle statistics.
23. The system of claim 20 , further comprising:
a sensor adapted to detect a laser beam return received through the output aperture; and
an optics controller adapted to steer the laser beam, in response to a relative position of the laser beam return on the sensor, by controlling an angular position of at least one of the deformable mirror and the steering mirror.
24. The system of claim 23 , further comprising a target illuminator adapted to direct a target illuminator beam toward a target, wherein a target illuminator beam return is generated by scatter of the target illuminator beam off the target and is received through the output aperture.
25. The system of claim 24 , wherein the target illuminator beam and the laser beam have different wavelengths.
26. The system of claim 24 , further comprising a dispersive element adapted to image each of the laser beam return and the target illuminator beam return onto separate areas of the sensor.
27. The system of claim 20 , further comprising scatter control elements disposed along the optical path.
28. The system of claim 20 , wherein the output aperture comprises a quarter wave plate.
29. A method of controlling a laser beam, the method comprising:
directing the laser beam out through an output aperture toward a target using a steering mirror;
detecting a laser beam return received through the output aperture, the laser beam return including scatter from the laser beam, the scatter resulting from the laser beam passing through a medium between the output aperture and the target, including detecting relative positions on a sensor of the laser beam return and a target illuminator beam return resulting from scatter of a target illuminator beam off the target;
adjusting the steering mirror in response to the scatter from the laser beam in the detected laser beam return.
30. The method of claim 29 , wherein adjusting the steering mirror includes adjusting an angular position of the steering mirror in response to the detected relative positions on the sensor.
31. A method of controlling a laser beam, the method comprising:
directing the laser beam out through an output aperture toward a target using a steering mirror;
detecting a laser beam return received through the output aperture, the laser beam return including scatter from the laser beam, including differentiating between a first scatter resulting from the laser beam incident upon the target and a second scatter resulting from the laser beam passing through a medium between the output aperture and the target;
adjusting the steering mirror in response to the scatter from the laser beam in the detected laser beam return.
32. The method of claim 31 , wherein differentiating between the first scatter and the second scatter includes analyzing a signal generated by the scatter using speckle statistics.
33. The method of claim 31 , further comprising measuring an angular bias present in the second scatter.
34. The method of claim 33 , wherein measuring the angular bias includes comparing a first signal part generated by the first scatter with a second signal part generated by the second scatter.
35. The method of claim 33 , wherein adjusting the steering mirror includes adjusting an angular position of the steering mirror in response to the measured angular bias.
36. A method of controlling a laser beam, the method comprising:
directing the laser beam out through an output aperture toward a target using a deformable mirror;
detecting a laser beam return received through the output aperture, the laser beam return including scatter from the laser beam, the scatter resulting from the laser beam passing through a medium between the output aperture and the target;
adjusting the deformable mirror in response to the scatter from the laser beam in the detected laser beam return.
37. The method of claim 36 , detecting the scatter includes detecting a wavefront of the scatter.
38. The method of claim 37 , wherein adjusting the deformable mirror includes adjusting the deformable mirror in response to the detected wavefront.
39. A method of controlling a laser beam, the method comprising:
directing the laser beam out through an output aperture toward a target using a deformable mirror;
detecting a laser beam return received through the output aperture, the laser beam return including scatter from the laser beam, including differentiating between a first scatter resulting from the laser beam incident upon the target and a second scatter resulting from the laser beam passing through a medium between the output aperture and the target;
adjusting the deformable mirror in response to the scatter from the laser beam in the detected laser beam return.
40. The method of claim 39 , wherein detecting the laser beam return includes detecting a first wavefront of the first scatter and detecting a second wavefront of the second scatter.
41. The method of claim 40 , wherein adjusting the deformable mirror includes adjusting the deformable mirror in response to a comparison of the first wavefront with the second wavefront.
42. The method of claim 39 , wherein differentiating between the first scatter and the second scatter includes analyzing the a signal generated by the scatter using speckle statistics.
43. The method of claim 39 , further comprising measuring an angular bias present in the second scatter.
44. The method of claim 43 , wherein measuring the angular bias includes comparing a first signal generated by the first scatter with a second signal generated by the second scatter.
45. The method of claim 43 , wherein adjusting the deformable mirror includes adjusting the deformable mirror in response to the measured angular bias.