Dynamic interferometry method for measuring wavelength

Abstract

It is theoretically proved the possibility of spectral selection of optical signal using the Michelson interferometer, one of the mirrors of which moves, providing the time variation of the path difference of one of beams of the interferometer according to a sawtooth law. It is shown that even a small displacement of the movable mirror (on the order a wavelength), at a predetermined controlled speed, due to the selective amplification of the received total power of the signal allows to detect the spectral density of optical radiation of a specified wavelength and to expand spectral range of the measurements, consistently changing, while maintaining the linearity of the offset mirrors, the speed of its movement. The limit value of the resolving power of the spectrometer is calculated, which in the optical range is 103 - 104 Hz, and is associated with the value of the time constant of the amplifier.