US Patent 7733493 Fourier transform spectrometer

The invention relates to a Fourier transform spectrometer comprising a binary grating with variable depth, the grating comprising a first set of mirrors and a second set of mirrors, the mirrors of the first set of mirrors and the mirrors of the second set of mirrors being arranged in an alternating order and at least one of the sets of mirrors being carried by fingers of a comb structure of a wafer, the spectrometer further comprising an actuator for prompting a motion of the second set of mirrors and a detector for detecting a radiation reflected by the grating, the mirrors being orientated in a plane defined by said wafer and said motion of the second set of mirrors being given by a translation in a direction vertical to said wafer plane.