Apparatus for light efficiency measurement

Motivated by a desire to determine the quantum efficiency of a relatively large number of GaAs injection lasers in order that some understanding of the relation between performance and structural parameters could be derived, a simple system for measuring the total light emission from such devices was sought. The method finally employed (and described herein) is generally applicable to any enclosure in which the walls are reasonably good diffuse reflectors. The calibration of the transfer efficiency of light from the source to a detector is effected by introducing a light absorbing element of known relative absorption coefficient and area. © 1963 The American Institute of Physics.