We propose to build a liquid crystal beam steerer (LCBS) which will put the alignment of interfering beams in precision metrology gauges under direct electronic control. The device will be non-mechanical and hysteresis free, it will require low power and voltage, and it will be low cost and easily incorporated into the current design of the SIM interferometric gauge. The device can be made polarization insensitive to allow it to operate on beams of arbitrary polarization. An LCBS can be used to actively remove pointing errors of a laser which travels between two objects whose relative distance is to be measured. It can also be used to correct tilt errors and other wavefront distortions that are relative to the interfering beams. These corrections can be applied remotely.
Potential Commercial Applications:Laser beam steerers have applications in secure communications, holographic optical storage and readout, and remote sensing. They are used to a large extent in the consumer market for barcode scanning. Solutions to the primary technical challenges in this proposal make possible a low cost 'electronic lens' which will make adaptive optics accessable to a wider market. Examples incude optical wafer inspection and retinal imaging.
