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Caesium iodide (chemical formula CsI) is the ionic compound of caesium and iodine. It is often used as the input phosphor of an x-ray image intensifier tube found in fluoroscopy equipment. Caesium iodide photocathodes are highly efficient at extreme ultraviolet wavelengths
C 1817 (OTTO) Cesium iodide, GR, 99.5%+ Cas 7789-17-5 - used as an input phosphor in x-ray image intensifier tube of fluoroscopy equipment. It is also used as an equipment for electromagnetic calorimetry in experimental particle physics.