PERFORMANCE OF EXTRINSIC FABRY-PEROT INTERFEROMETER BASED ON GRADED-INDEX LENSES FOR A FABRY-PEROT CAVITY WITH SURFACE ERRORS

摘要

Interference contrast is an important parameter for extrinsic Fabry-Perot interferometer (EFPI) based on graded index (GRIN) lenses. It determines the signal-to-noise ratio (SNR) and the measurement accuracy. We discuss the influence of Fabry-Perot (FP) cavity surface errors, which are inevitable in controlling the interference contrast during the manufacturing procedure. Our theoretical analysis and results of numerical simulations demonstrate that the surface errors diminish the interference contrast - the larger the surface error, the smaller the interference contrast. The results obtained contribute to the EFPI application in fiber sensors.