Absorption of Light in Gases
Abstract
Evaluation of a method for measuring molecular absorptivities is being conducted. Sound pulses generated by the absorption of ruby laser light are to be focused on a collodian membrane microphone; Membrane motion of as little as 5 Angstroms will be detected by making the membrane one reflector of an optical resonator illuminated by a frequency stabilized CW helium-neon laser. Signals will be observed in the frequency control loop. Wavelength scanning of the ruby laser will be done by temperature control over a 2 Angstroms region. Optical-thermal relaxation times have been studied. They are less than 10 to the minus 8th power seconds, too short to disturb the acoustic pulse. Ruby laser wavelength will be calibrated with a wavelength reference lamp, an etalon, and a grating, to provide resolving power.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 30, 1965
- Accession Number
- AD0467451
Entities
People
- John G. Atwood