Dynamic method for measuring the non-linearities of photoelectric detectors

摘要

The photocurrent of a nonlinear radiation detector contains a signal with the frequency omega sub 1-omega sub 2 when exposed to two chopped light beams with the chopper frequencies omega sub 1 and omega sub 2. The amplitude of the intermodulation signal is proportional to the non-linearity. So it is possible to measure nonlinearities in a direct way without evaluating small differences of large quantities. The method shown requires less stability of light sources than classical methods. A dependence of the intermodulation signal on the chopper frequencies gives additional information about time dependent nonlinearities.