Improvements in or relating to windows for use in the infra-red region of the spectrum

摘要

626,163. Colour screens. PARSONS & CO., Ltd., C. A., and MARTIN, A. E. March 24, 1947, No. 8020. [Class 97 (i)] A window passing infra-red radiation comprises a thin mica sheet supported at or near its centre by means resisting pressure differences on opposite sides of the window. As shown, the sheet a is curved by the pressure of a protuberance b carried by a spider c. Alternatively the protuberance may be omitted and the sheet flat or the spider may be replaced by a perforated metal plate or a wire gauze.