Monitor with radiation source and detector - has evaluation circuit with reference with inbuilt thermal elements and projection via lens

摘要

A monitoring system consists of a radiation source and a radiation detector followed by an evaluation circuit. It reduces the chances of triggering the fault alarm unnecessarily. The radiation source is designed as a reference surface which is kept at a given temp. value relative to ambient temp. by heating or cooling. The radiation detector is an opto-electrical radiation detector, which is sensitive to a given wavelength at a given temp. The reference surface contains a built-in thermal element which will measure the temp. There is a good thermal element which measures the ambient temp. It is kept in a medium or in the ground if the monitoring system is out of doors. The reference surface is projected onto the detector via a lens.