Optimal optical path difference of an asymmetric common-path coherent-dispersion spectrometer.

Optical path difference (OPD) is a very significant parameter in the asymmetric common-path coherent-dispersion spectrometer (CODES), which directly determines the performance of the CODES. In order to improve the performance of the instrument as much as possible, a temperature-compensated optimal optical path difference (TOOPD) method is proposed. The method does not only consider the influence of temperature change on the OPD but also effectively solves the problem that the optimal OPD cannot be obtained simultaneously at different wavelengths.

W-shaped common-path interferometer.

We present a novel static W-shaped common-path interferometer. In particular, the W-shaped common-path corner-cube retroreflector interferometer (W-CPRI) is introduced via detailed analysis of its working principles and performance. It comprises two corner-cube retroreflectors (CCRs), a reflecting mirror (RM), and a beam splitter.