A long range translation actuator designed for optic and robotic applications is presented. Specifically, the microstage is designed to operate as the moving mirror in a miniature version of a traditional Michelson Fourier transform spectrometer. The translational microstage utilizes an electromagnetic actuation mechanism to realize linear translation of centimeters of precision travel. Motion is constrained in the normal and lateral directions using silicon dovetail microjoints. The electromagnetic actuation is based on macro linear synchronous motor design using a linear array of microcoils. Microcoils are arranged in a 3-phase configuration to enable both velocity and direction control. The electromagnetic force is characterized by finite element computer simulations to develop the input signal for translational travel at constant velocity. Optical position detection was used to measure the translation with time. Operation was demonstrated at various drive frequencies.
Prototypes of micromachined tunable infrared optical filters are being produced. Micromachining silicon for use in these filters requires the integration of multilayer dielectric optical coatings such as ZnSe/ThF4. These coatings are novel materials for integration with microlithographic processing. Devices were engineered and a process flow was developed to avoid contaminating processing tools with the coating. A method for patterning the coating was developed. Low-temperature bonding techniques have been explored and tested. Fabrication issues for these micromachined devices are discussed.
A concept for a solar-powered laser is presented which utilizes an intermediate blackbody cavity to provide a uniform optical
pumping environment for the lasant, typically CO or C02 or possibly a solid state laser medium. High power cw blackbody-
pumped lasers with efficiencies on the order of 20% or more are feasible. The physical basis of this idea is reviewed. Small scale experiments using a high temperature oven as the optical pump have been carried out with gas laser mixtures. Detailed calculations showing a potential efficiency of 35% for blackbody pumped Nd:YAG system are discussed.