Theoretical and experimental study on a compact static spectropolarimeter

Spectropolarimetry is the technique that spectrally resolves polarisation properties of light. The conventional spectropolarimeter generally suffer from vibration, electrical noise, and alignment difficulty introduced by the mechanical or electro-optic device for polarization control, such as a rotating compensator and a liquid crystal device, such a polarization controlling element generally requires the considerable volume as well as the electronic driving cables, which has been the major obstacles for the reduction in the size of the spectropolarimeter. This paper presents a compact configuration of the channeled spectropolarimeter designed to increase the stability of the state of polarization measurement, the whole spectropolarimeter system without any internal moving parts, electrically controllable or micro-components, which enables us to determine all the parameters related to the spectral dependence of the state of polarization of light at once from a single measurement. In this spectropolarimeter system, multiple-order retarders are utilized to generate a channeled spectrum carrying information about the wavelength-dependent multiple parameters of polarization of light. The theory analysis and some aspects of our proof of concept experiments are given in this paper.