A depolarizer is usually used to reduce the polarization response of the spectrometer. On the basis of LYOT depolarizer, a depolarizer composed of two quartz crystals with the same wedge angle is designed and developed. Based on the matrix optics theory, this paper studies the relationship between the residual polarization degree of a LYOT depolarizer and the polarization angle of incident light, wavelength, spectral bandwidth, crystal central thickness. The residual polarization degree of a LYOT depolarizer is tested on the polarization sensitivity tester, and the test results are in good agreement with the theoretical analysis results. The LYOT quartz depolarizer can meet the requirements of spectral radiation measurement, and is of strong engineering practice.
The novel support structure design of high stability for space borne primary mirror is presented. The structure is supported by a ball head support rod, for statically determinate support of reflector. The ball head assembly includes the supporting rod, nesting, bushing and other important parts. The liner bushing of the resistant material is used to fit for ball head approximated with the reflector material, and then the bad impact of thermal mismatch could be minimized to minimum. In order to ensure that the structure of the support will not be damaged, the glue spots for limitation is added around the reflector, for position stability of reflector. Through analysis and calculation, it can be seen that the novel support structure would not transfer the external stresses to the reflector, and the external stresses usually result from thermal mismatch and assembly misalignment. The novel method is useful for solving the problem of the bad influence form thermal stress and assembly force. In this paper, the supporting structure is introduced and analyzed in detail. The simulation results show that the ball head support reflector works more stably.