Abstract: Compact beam manipulators employ one or more Risley prism sets with or without a parallel plate translator. One beam manipulator contains a plate mounted to permit pitch and yaw adjustments and a prism set mounted to permit rotations. The rotations of the prisms adjust a beam direction, and adjustment of the plate adjusts the beam position. Another beam manipulator contains a prism set mounted to permit rotations and pitch and yaw adjustments of the prisms. The rotations and pitch and yaw adjustments provide coupled changes in the position and direction of a beam, and iterative adjustments alternate between rotating prisms to change the beam direction and the adjusting pitch and yaw to change the beam position. The iterative adjustments are complete when the beam has a target position and a target direction to within required tolerances. Gluing elements to optic holders minimizes stress-induced birefringence and temperature and humidity effects.

Abstract: Compact beam manipulators employ one or more Risley prism sets with or without a parallel plate translator. One beam manipulator contains a plate mounted to permit pitch and yaw adjustments and a prism set mounted to permit rotations. The rotations of the prisms adjust a beam direction, and adjustment of the plate adjusts the beam position. Another beam manipulator contains a prism set mounted to permit rotations and pitch and yaw adjustments of the prisms. The rotations and pitch and yaw adjustments provide coupled changes in the position and direction of a beam, and iterative adjustments alternate between rotating prisms to change the beam direction and the adjusting pitch and yaw to change the beam position. The iterative adjustments are complete when the beam has a target position and a target direction to within required tolerances. Gluing elements to optic holders minimizes stress-induced birefringence and temperature and humidity effects.

Abstract: Compact beam manipulators employ one or more Risley prism sets with or without a parallel plate translator. One beam manipulator contains a plate mounted to permit pitch and yaw adjustments and a prism set mounted to permit rotations. The rotations of the prisms adjust a beam direction, and adjustment of the plate adjusts the beam position. Another beam manipulator contains a prism set mounted to permit rotations and pitch and yaw adjustments of the prisms. The rotations and pitch and yaw adjustments provide coupled changes in the position and direction of a beam, and iterative adjustments alternate between rotating prisms to change the beam direction and the adjusting pitch and yaw to change the beam position. The iterative adjustments are complete when the beam has a target position and a target direction to within required tolerances. Gluing elements to optic holders minimizes stress-induced birefringence and temperature and humidity effects.

Abstract: A wavelength tracking compensator for a laser interferometer measurement system comprises a stable physical standard optical cavity and a double path, differential interferometer mounted on a baseplate. The interferometer monitors the apparent changes in the cavity's length caused by actual changes in the index of refraction of the surrounding air. The cavity is supported with a temperature compensated mount that utilizes the principle of differential thermal expansion of two different metals to create a mount which exactly matches the coefficient of expansion of the cavity material. A semi-kinematic mount supports the double path, differential interferometer and allows the interferometer to be accurately aligned to the cavity with three rotational degrees of freedom to prevent any cosine error in the cavity's optical path length measurement, to prevent polarization leakage, and to maximize optical power at the receiver.