Vibration monitoring in optical and opto-electronic beam guiding systems

• US 20040182997A1
• Filed: 03/20/2003
• Published: 09/23/2004
• Est. Priority Date: 03/20/2003
• Status: Active Grant

• Current Assignee: Newport Corporation (MKS Instruments Incorporated)
• Original Assignee: New Focus Inc. (MKS Instruments Incorporated)
• Inventors: Green, Evan D. H.
• Granted Patent: US 6,987,626 B2
• Time in Patent Office: Days
• US Class Current: 250/227.14
• CPC Class Codes: G02B 27/646 compensating for small deviations, e.g. due to vibration or shake movement of one or more optical elements for control of motion blur in cameras, projectors or printers G03B2205/0007; image stabilisation in cameras peculiar to the presence or use of an electronic image sensor H04N23/68

Abstract

An optical component mount with beam deviation monitoring and beam guiding system using such optical component mounts. The optical component mount has a location for mounting an optical element thereon for operating on the beam and at least one sensor attached to the optical mount at a predetermined position. The predetermined position is selected depending on the state of the optical component mount. The state can be, e.g., a vibrational state or a thermal expansion state. The predetermined position is chosen near or at an anti-node of at least one mode contributing to the state but not at a node of any mode expected to contribute to the state of the optical mount. The state of the optical mount is determined based on the signals obtained from the at least one sensor, which can be an accelerometer in the case of monitoring a vibrational state or a temperature sensor in the case of monitoring a thermal expansion state. The sensor is preferably embedded in the optical mount and the deviation of the beam is then determined from the state of the optical mount. Optical mounts according to the invention can be used in any beam guiding system including but not limited to those found in optical and/or opto-electronic assemblies.

Claims

1. An optical component mount with beam deviation monitoring, said optical component mount comprising:

a) a location for mounting an optical element for operating on a beam;

b) at least one sensor attached to said optical component mount at a predetermined position for determining a state of said optical component mount;

such that a deviation of said beam is determinable from said state.

2. The optical component mount of claim 1, wherein said state is selected from the group consisting of a vibrational state and a thermal expansion state.

3. The optical component mount of claim 1, wherein said predetermined position is at an anti-node of at least one mode comprising said state of said optical component mount.

4. The optical component mount of claim 1, wherein said predetermined position is not at a node of any mode comprising said state of said optical component mount.

5. The optical component mount of claim 1, wherein said sensor is selected from the group consisting of acceleration sensors and temperature sensors.

6. The vibration monitor of claim 5, wherein said sensor is embedded in said optical component mount.

7. The optical component mount of claim 1, further comprising a sensor circuit in communication with said sensor for determining said deviation from said state.

8. The optical component mount of claim 1, further comprising a compensator in mechanical communication with said optical component mount for counteracting said state.

9. The optical component mount of claim 8, wherein said compensator comprises an element selected from the group consisting of piezoelectric actuators, voice coil electromagnetic actuators, servo motors and stepper motors.

10. The optical component mount of claim 1, wherein an optical element is mounted in said location, said optical element being selected from the group consisting of mirrors, lenses, gratings, beam-splitters, sources and detectors.

11. The optical component mount of claim 10, wherein said optical component mount is selected from the group consisting of mirror mounts, translation stages, tilt stages, rotational stages, goniometers and optical breadboards.

18. The beam guiding system of claim 11, further comprising a sensor circuit in communication with said at least one sensor for determining said deviation from said state.

19. The beam guiding system of claim 11, further comprising at least one compensator in mechanical communication with said at least one of said optical component mounts for counteracting said state.

20. The beam guiding system of claim 19, wherein said at least one compensator comprises an element selected from the group consisting of piezoelectric actuators, voice coil electromagnetic actuators, servo motors and stepper motors.

12. A beam guiding system with beam deviation monitoring, said beam guiding system comprising:

a) a plurality of optical component mounts;

b) a plurality of locations for mounting optical elements on said optical component mounts for operating on a beam;

c) at least one sensor attached to at least one of said optical component mounts at a predetermined position for determining a state of said at least one optical component mount;

such that a deviation of said beam is determinable from said state.

13. The beam guiding system of claim 12, wherein said state is selected from the group consisting of a vibrational state and a thermal expansion state.

14. The beam guiding system of claim 12, wherein said predetermined position is at an anti-node of at least one mode comprising said state of said at least one of said optical component mounts.

15. The beam guiding system of claim 12, wherein said predetermined position is not at a node of any mode comprising said state of said at least one of said optical component mounts.

16. The beam guiding system of claim 12, wherein said at least one sensor is selected from the group consisting of acceleration sensors and temperature sensors.

17. The beam guiding system of claim 16, wherein said sensor is embedded is said at least one of said optical component mounts.

21. The beam guiding system of claim 12, wherein at least one of said optical elements is selected from the group consisting of mirrors, lenses, gratings, beam-splitters, sources and detectors.

22. The beam guiding system of claim 21, wherein said at least one of said optical component mounts is selected from the group consisting of mirror mounts, translation stages, tilt stages, rotational stages, goniometers and optical breadboards.

23. The beam guiding system of claim 12, further comprising an evaluation unit for translating said state of said at least one optical component mount into a total deviation of said beam.

24. The beam guiding system of claim 12 comprising a laser pointer.

25. A method for controlling a deflection of a beam propagating in a beam guiding system comprising optical component mounts having locations for mounting optical elements thereon, said method comprising:

a) attaching at least one sensor to at least one of said optical component mounts at a predetermined position for determining a state of said at least one of said optical component mounts;

b) translating said state into a deflection of said beam.

26. The method of claim 25, wherein said state is selected from the group consisting of a vibrational state and a thermal expansion state.

27. The method of claim 25, wherein said predetermined position is selected at an anti-node of at least one mode comprising said state of said at least one of said optical component mounts.

28. The method of claim 25, wherein said predetermined position is not at a node of any mode comprising said state of said at least one of said optical component mounts.

29. The method of claim 25, further comprising counteracting said state.

30. The method of claim 25, wherein said at least one sensor is attached to said at least one of said optical component mounts by embedding.