Measuring temp. variations by laser radiation - superimposing laser single frequency on second, frequency stabilised reference laser

摘要

The measuring of temp. variations, using a laser operating in single frequency mode, involves superimposing the single frequency of the laser onto a second, frequency stabilised reference laser. The sum and difference frequencies, arising from interference, are used as the measuring values for temp. variation. The superposition signals of both lasers are detected by a photodiode, processed by a HF analyser, and displayed. USE/ADVANTAGE - For precise process control etc., with improved measuring precision over a dynamic range.