Compact ultrahigh resolution interferometric spectrometer

A compact ultrahigh resolving power spectrometer is presented, which combines a Fabry-Perot interferometer (FPI) and a static stepped-mirror interferometer (SMI). The FPI needs to scan N steps, one spectrum per step is obtained from the SMI, and a total of N spectra constitute an ultrahigh resolution spectrum. Compared with Michelson-type interferometers for ultrahigh resolution spectral measurements, the spectrometer is much smaller in physical size and shorter in measurement time. Compared with the combination of a FPI and a Michelson-type interferometer, the spectrometer has much shorter measurement time and higher stability. Preliminary numerical simulations are given by two examples. The spectrometer offers a unique concept that not only provides resolving power higher than 1,000,000 in near-infrared, short-wave infrared or mid-wave infrared region but also achieves short measurement time and small physical size.