Techniques of flash photolysis

Abstract— The design of a typical flash photolysis equipment is considered in detail and the factors limiting the time resolution and the sensitivity are analyzed. The characteristics of low pressure discharge lamps are compared with those of high pressure arcs, of exploding foils and of the electromagnetic ‘pinch’ discharge. For the analytical flash, operating at a much lower power level, many satisfactory designs exist which give a good continuum and short duration. Methods of improving the optical system are discussed, and the special advantages of using a microscope optical system for investigating substances with high extinction coefficients are illustrated by an account of recent work on chlorophyll.