On the possible use of photo thermal optical bistability as a temperature sensor

Abstract

The development of optical information processing units leads to the requirement of sensors with optical output for various physical variables. Here, the process of photo-thermally induced absorptive Optical Bistability (OB) in CdS is used to measure temperatures optically. At constant incident light intensity, switching processes in the transmitted light intensity can be induced by changing the environmental temperature. Thus, the system acts as a temperature threshold sensor. Additionally, the characteristic hysteresis loop (transmitted light intensity as a function of the incident light intensity) changes with the environmental temperature. Using the relative width of the hysteresis loop the temperature can be measured directly. A proposal for the realization of a miniaturized device is given.