Interferometer having multiple scan carriages and two pairs of bearing flexures to maintain mirror alignment

摘要

An interferometer 101 suitable for a Fourier transform infrared spectroscopy system includes a fixed assembly 140 including a base 141, a beam splitter assembly (4, Fig. 1) and a fixed mirror (9, Fig. 1), and a movable assembly 120 including an upper scan carriage 130, a lower scan carriage150 and a movable mirror 8 connected to the lower scan carriage 150. A pair of inner bearing flexures 131a, 131b is connected to the base 141 and the upper scan carriage 130, enabling movement of the upper scan carriage relative to the base, and a pair of outer bearing flexures151a, 151b is connected to the upper and lower scan carriages 130, 150, enabling movement of the lower scan carriage relative to the upper scan carriage. The movement of the upper and lower scan carriages enables a scan movement of the movable mirror 8 in a scan direction SD restricted such that the scan movement maintains a plane containing the movable minor parallel to planes containing the movable mirror at respective distances between the movable and fixed assemblies during the scan movement.