Compact high resolution interferometer with short stroke reactionless

Abstract

An interferometer or spectrometer having a short stroke reactionless drive mechanism is disclosed. The interferometer includes a housing, and a beamsplitter for reflecting an input beam along a fixed optical path and for transmitting the input beam along a scanned optical path. A nonmoving reflecting arrangement is disposed along the fixed optical path and includes first and second nonmoving mirrors disposed to reflect the input beam multiple times therebetween, and a backreflecting device disposed at a final bounce position of the input beam to return the optical beam back to the beamsplitter. A scanning mechanism is disposed along the scanned optical path that includes third and fourth mirrors supported by flexible members or flexure blades that are coupled to the housing, and a backreflecting device at a final bounce position of the input beam to return the optical beam back to the beamsplitter. The drive mechanism is coupled to the third and fourth mirrors of the scanning mechanism for driving the respective mirrors so that the optical path difference of the scanned optical path is either increased or decreased relative to the fixed optical path. The backreflecting devices may comprise retroreflectors or flat mirrors, for example. The drive mechanism may comprise linear actuators, such as voice coil motors, or the like.