Improvements In Long Path Absorption Cell Measurements.
Abstract
Improvements which greatly reduce the data acquistion time and increase the accuracy of long-path absorption cell measurements upon which the choice and further development of many Army laser-based systems depend are discussed. path differencing, a new technique for measuring absorption coefficients, is described. Path differencing effectively gives the massive cells and intricate optical and detection systems used in long-path absorption cell experiments the real-time calibration of double-beam spectrometer systems. This calibration results in a factor of 4 to 5 in improvement in reproducibility. Techniques of weighted averages are discussed for obtaining best fit absorption data, and a detection and correction scheme for system nonlinearities is given. A method for determining errors in absorption coefficients from data at different partial pressures of an absorbing gas and characterizing nonlinear pressure dependencies is also included. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1976
- Accession Number
- ADA023079
Entities
People
- Wendell R. Watkins
Organizations
- United States Army Communications-Electronics Command