CO(2) (10.6-microm) atmospheric propagation enhancement due to off-line center tuning.
A new analysis is presented for the atmospheric transmission of the CO(2)(P-20) line, which includes pressure shift, bleaching, and tuning off-line center. The results indicate that absorption is negligible above 25 km for an atmospheric CO(2) laser, even at line center, with the resulting transmission equal to 0.5 from sea level and 0.75 from 2.5 km altitude, midlatitude summer. Cavity tuning of about 0.1 cm(-1) produces a transmission of 0.97 from 2.5 km, with a corresponding large decrease in thermal blooming, but with little decrease of cavity efficiency for a well-saturated atmospheric pressure cavity, since the linewidth of the latter is considerably larger than that of the atmosphere.
Sutton
G W
GW
Douglas-Hamilton
D H
DH