GB751058A - Mounting of fluorescent and phosphorescent elements - Google Patents

Abstract

751,058. Radiation detector. RUDERMAN, I. W. June 18, 1954 [July 16, 1953], No. 17991/54. Class 40 (3). [Also in Group XL (a)] A crystalline phosphor is coupled optically to a sheet of glass or glass substitute by a transparent substance having substantially permanent cold flow characteristics and refractive index between 1.403 and that of the glass or glass substitute, the substance being retained by sealing material. High viscosity silicone fluid 4 couples the crystal 5 and the glass or silica glass window 1, an aluminium mounting ring 3 enclosing them and being held in position by resin cement 6. The glass window 1 is retained on a can 7 by a ring 8 and cement 9, 10. The phosphor may be a single crystal of an alkali halide actuated by a heavy metal, e.g. thallium or tin, coated with light reflecting material, e.g. T1-2. The interior of the can may be silvered and vacant space filled with powdered Mg 2 . There may be a window in the can for admitting ultraviolet or other less-penetrating radiation. Fig. 5 shows a modification for radiation of low penetrating power, a metal foil 17, e.g. of polished aluminium, being placed in direct contact with the crystal the whole cemented in a cylinder 7. The crystal may be held in position by a neoprene ring fitting in an annular groove in the enclosing ring, Fig. 6 (not shown). The phosphor may be organic, and a powdered phosphor with binder may replace the single crystal.