Fabry Perot detector for low coherence interferometry

Abstract

Two theoretical detector have been designed for different wavelengths based on Fabry Perot cavities for application in the frequency domain low coherence interference (FD-LCI) technique. A one-dimensional axial detector consisting of a variable-width cavity with a photodiode and another radial detector with fixed cavity with a linear array or camera. Theoretical feasibility was demonstrated by performing simulations of Gaussian beams propagating through cavities with different characteristics. The parameters were optimized in order the detectors are centered at 850 nm, with ranges of 60 nm and resolution below the nanometer for waist beam of 500 µm, typical conditions of the sources and detectors used in FD-LCI. In addition, the design contemplates the possibility of using them simultaneously.