摘要 |
A mechanical device for tilting an optical element consisting of one or more actuators attached to a support element supporting an optical filter or other optical device is provided. In one preferred embodiment of the present invention, a rigid support element is free to move at one end, or is attached by a hinge at one end to an actuator while movement of its second end is restrained, resulting in tilting of the support element when the actuator is activated. In another embodiment of the present invention, a deformable support element is rigidly attached to the actuator at one end while movement of the second end of the support element is restrained, resulting in bending of the support element and tilting of the optical element upon movement of the actuator. In yet another embodiment, a deformable support element is rigidly attached to two actuators, resulting in bending of the support element when the actuators are activated. The actuator is preferably a piezoelectric device that is activated by application of an electrical voltage. Alternatively, the actuator is thermally, electrostatically, electromagnetically, or magnetically activated. A method is provided of filtering an incident light beam based on tilting a filter for passing light in the incident light beam within a predetermined characteristic wavelength band that is a function of the angle of incidence of the incident light beam upon the filter. The filter is tilted to change the angle of incidence by activating an actuator that is attached to and changes the shape or orientation of the support element whereon the filter is mounted. Preferably, the filter is tilted in response to a feedback signal indicative of the angular position of the filter. Preferably, the feedback signal is based on light reflected from the filter. Alternatively, the feedback signal is based on light transmitted by the filter, or is a signal from a sensor responsive to movement of the filter or of a mechanical element associated therewith.
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