A New Approach to Making Absolute Frequency Measurements for High Resolution Spectroscopy.

摘要

High resolution spectroscopy with tunable lasers in the near infrared frequency range requires an absolute frequency measurement technique to allow Doppler-limited spectroscopy to be done. A feasibility study of a new technique,involving the ratioing of the Doppler shift frequencies of an unknown frequency laser and a known frequency standard laser,was proposed. The feasibility study emphasized showing how accurately the ratio of the Doppler shift frequencies could be measured,since the ratio of the Doppler shift frequencies is equal to the ratio of the original laser frequencies. The feasibility experiment used a HeNe and a HeCd laser and a screw-worm driven translation stage for moving a mirror back and forth to produce the Doppler shift frequencies.