Fourier spectrometer system for determining optical spectrum of radiation - uses Fourier transformation of measured optical interferogram so that measuring and reference beams produce interferogram of measured radiation to be analysed

摘要

The spectrometer has an electronic assembly (1) connected to a detector (D) of a reference signal (SR), which carries out a zero passage detection, as well as determining a time between two activations of a digital counter. In addition it transforms this value in to a speed value, so that the speed determined together with the drive current, given in the preceeding regulating pulse, forms the input signal for the following connected extrapolation filter. A condition computation for the condition variables speed and acceleration of the optical path difference is computed in advance, from the incoming input signal by means of the extrapolation filter. As a result of the extrapolations as output values, the readiness setting of the trigger signal for the interferometer results, at the output of the extrapolation filter. ADVANTAGE - Gives optimum speed regulation. Lower reference frequency. Scanning frequency of interferogram is maintained or increased.