Laser referencing system for refractively scanning interferometer

摘要

A laser referencing system is disclosed which is used in a refractively scanning interferometer. The interferometer optics comprise a fixed wedge-shaped prism having a beamsplitter surface, a movable wedge-shaped prism, and two corner cube reflectors. A laser clocking beam enters the interferometer on a path below the infrared analytical beam, and leaves the interferometer on a path above the infrared beam. Quadrature control of the laser beams is used to control the ends of the scanning sweeps, eliminating the need for a third, "white light" interferometer beam. ZPD alignment is accomplished by horizontal adjustment of the fixed beamsplitter prism. The interferometer optics are supported three-dimensionally in a cast shell.