Accession Number : AD0655437

Title :   HELIUM-NEON LASER DISCHARGE PARAMETER STUDY.

Descriptive Note : Master's thesis,

Corporate Author : NAVAL RESEARCH LAB WASHINGTON D C

Personal Author(s) : Whitney,Wayne T.

Report Date : 21 JUN 1967

Pagination or Media Count : 51

Abstract : An experimental study was made to determine which energy level is dominant in limiting the output power of the helium-neon laser. This was done by comparing laser power versus discharge current data for the three main laser transitions, with the temperature and pressure as parameters. Such a comparison is informative because two of the laser transitions (0.6328 and 3.39 microns) share a common upper level (3s2); and two (0.6328 and 1.15 microns) share a common lower level (2p4). Relative saturation behavior indicates that at low pressures the upper level population rate controls the output power of all three laser lines; and at high pressures (above 1 torr) the lower level depopulation rate is more important for the 0.63 and 1.15 microns lasers. The optimum pressure for maximum output of the 0.6328 micron laser occurs at an intermediate pressure (0.7 torr) where both effects are important. All of the data were taken on the same tube, (8 mm. i.d.), utilizing ultra high vacuum techniques to maintain gas purity. It was found that an increase in the laser tube wall temperature will produce an increase in laser power at high pressures (as much as 500% for 1.15 microns); but will decrease the power at low pressures. Also of interest in the data is the fact that the 1.15 micron line can be made to oscillate at total pressures at least as high as 20 torr. (Author)

Descriptors :   (*GAS LASERS, *ATOMIC ENERGY LEVELS), HELIUM, NEON, GAS DISCHARGES, ELECTRON TRANSITIONS, LINE SPECTRA, PRESSURE

Subject Categories : Lasers and Masers

Distribution Statement : APPROVED FOR PUBLIC RELEASE