Monocrystalline lithium fluoride (LiF) windows are used in mineral physics research. Optical Pyrometric Measurements (OPM) during shock tests are done through LiF windows on which a few mm thick plates of tested materials are fixed. Current OPM requires the plates to be glued on the LiF windows. However, this glue is an undetermined source of error for OPM. This study deals with plasma spraying to deposit a tin coating directly on to the polished LiF windows as a substitute to the plate/glue/LiF system. Although seldom used for low melting point materials, plasma spraying was shown to be the appropriate technique for this original material couple and application especially for its flexibility. The study confirmed the feasibility of plasma spraying of tin on polished surfaces of LiF windows. Scanning electron microscopy (SEM), electron probe micro-analysis (EPMA), hydrostatic weigh measurements (HWM), optical and confocal microscopy were used to characterize the coating and substrate.