Characteristics and Applications of Photo-Electric Cells

Abstract

The paper deals first with the theory of photo-emission and the properties of photoemissive cells. The various types of cathode which have been developed are described. Information is then presented on gas-filled cells and photo-electric multipliers. Mention is made of colour response, fatigue effects, dark current, noise, frequency response and associated circuits. The mechanisms and characteristics of various types of photo-voltaic and photo-conductive cells are then discussed, and some details of semi-conductor photocells are included. The applications of photocells to photometry, spectrophotometry, astronomy, radiation detection, recording of transient optical phenomena and in reflectometers, fluorometers, refractometers, colorimeters and turbidimeters are briefly discussed. Some infra-red photo-electric equipment is mentioned and finally a large number of miscellaneous photocell applications are listed.