Eng R S, Mantz A W, Todd T R
Appl Opt. 1979 Oct 15;18(20):3438-42. doi: 10.1364/AO.18.003438.
The detection sensitivity of a long-path atmospheric pollutant monitor using tunable diode lasers has been greatly improved to about 0.1%. These improvements directly result from measurements made on the low frequency noise characteristics of several diode lasers and the temporal spectrum of atmospheric turbulence. Optimum modulation frequencies are given, and an improved optical design is recommended.
