A Modular Michelson Interferometer for Fourier Transform Spectrochemical Measurements from the Mid-Infrared to the Ultraviolet

Abstract

A versatile Michelson interferometer system capable of Fourier transform spectrochemical measurements from the uv to the mid-ir has been developed in our laboratory. Laser fringe referencing is used in the interferometer system to sequence digitization and the velocity of the air bearing mirror drive system is controlled with the laser fringe signal using phase-locked loop techniques. Interferograms can be time averaged under white light interferogram control. The modular design of the interferometer is such that the detector, beamsplitter, and source can all be changed and the interferometer realigned in a matter of a few minutes. Interferograms are acquired and transformed with a PDP 11 minicomputer. This system is described in detail and its application to spectrochemical measurements in the mid-ir and uv-visible is briefly illustrated.