Electronic design of space-based LCVR measurement system

Liquid crystal variable retarder (LCVR) has become a new research area for space-based optical instruments because of its fast modulation speed, light weight and no moving parts. etc. Nevertheless, the molecule in LCVR is a type of liquid crystal polymer, its space adaptability needs to be verified. Because we cannot simulate the space environment absolutely in the ground, it is necessary to develop a LCVR experimental device to study the electro-optic performance of LCVR in space. In this paper,the stability of a LCVR measurement system is analyzed, and an electronic measurement scheme for LCVR's retardation-voltage curve is designed. Firstly,a zero-calibration method is proposed to improve the stability of the driving voltage for LCVR. Then,the high precision temperature control is realized by using frequency conversion error control method. The driving stability reaches 99. 3% and the constant temperature accuracy reaches (35 +/- 0. 1) degrees C. Based on this, the mechanical, thermal and electromagnetic compatibility tests are carried out. The experimental results show that the electronic system are stable,and the first space photo-electric measurement system for LCVR is successfully developed in China,which is of great significance to the application of LCVR in space.