Analytical Description of a Fabry–Perot Photoelectric Spectrometer

An analytical expression for the response of a complete Fabry-Perot photoelectric spectrometer to a line profile is derived. The case of a doppler-broadened Lorentzian profile examined by a spectrometer comprised of an etalon of variable thickness and reflectivity, with surface defects consisting of spherical curvature, as well as microscopic flatness imperfections, a finite exploring slit in front of the photodetector, and bandwidth limiting circuits is considered. Some of the properties and uses of the expression obtained are discussed.