Verfahren zum Betrieb und zur Wellenzahlkalibrierung eines Interferometers nach Michelson

摘要

The method is used for triggering the digitisation of interferograms. It involves triggering an analogue-to-digital converter (2) connected after the interferometer detector (10) with pulses of frequency selected to satisfy the sampling theorem. The start of movement of a mirror (16) and hence of the measurement process is detected whereby equidistant signal scanning is ensured by a constant mirror motion and trigger frequency. The step width for a Fourier transformation is set to one and spectral lines or bands of accurately known wave number sought in the spectrum. A stretching factor is determined from the wave numbers for wave number calibration and used to multiply computed abscissa values. USE/ADVANTAGE - For use with Michelson interferometers. The triggering is achieved very reliably and at low cost without direct distance measurement.