Abstract

Intracavity laser absorption spectroscopy (ICLAS) is an extremely sensitive method of measurement of very weak absorption spectra. ICLAS is based on very high sensitivity of a broadband laser to narrow absorption lines of the gas tilling the cavity, while the broadband cavity losses are compensated by the gain. This allows to obtain an equivalent absorption path as large as 30000 km and thus to detect absorption lines as weak as 10⁻¹¹ cm⁻¹. The spectral range of ICLAS is determined by the avalability of broadband homogeneously broadened laser media. Dye, color center and vibronic crystal lasers have been used for ICLAS in the range from 0.4 to 1.5 microns¹.

© 1996 IEEE