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During the last two decades, Liquid Crystal Variable Retarder (LCVR) technology has matured and advanced as reliable and well-understood technology for ground applications to the point of being recently integrated in space-based optical instruments for the first time. LCVR cells use nematic liquid crystals to electronically tune the birefringence of the device in order to control the polarization of the transmitted light. The possibility to modulate the light polarization by means of an applied voltage offers the advantage of replacing the conventional rotary mechanisms, dedicated to carry the polarizing optics. Consequently, LCVR cells represent an excellent electro-optic solution to include in the design of space instruments where polarized light modulation is necessary. However, to validate the applicability of a LCVR cell to a space mission it is imperative to test its survivability in its exposure to conditions representative of the space environment. In this article, we summarize the activities performed to test the survivability of two commercial LCVR samples after their exposure to space-like environment for radiation and we report the result obtained by analyzing the radiation dose impact on the cell performances. The under-test samples have been produced by Meadowlark Optics Inc and designed for operation at 547 nm. We exposed the cells to multiple levels of gamma radiation dose, measuring their response time after each dose. To verify the impact of the accumulated radiation dose on the optical performances of the LCVR, we chose as indicators the retardance versus voltage, the transmission, and the response time. We measured these quantities before and after the whole test campaign and compared the two datasets to verify if gamma rays introduced any alterations in cell performances.
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