Multichannel recording of absorption spectra obtained by intracavity laser spectroscopy

A multichannel photoelectric system was developed for recording absorption spectra obtained by intracavity laser spectroscopy. Such a recording system was chosen because the features of the kinetics of the spectral distribution of a broad-band laser, having frequency-dependent losses in its resonator, make it impossible to use single-channel successive recording of the spectra. The use of multichannel recording enabled the dynamic range to be broadened and the accuracy and sensitivity of measurement of the absorption coefficients to be increased. Absorption coefficients in the range $3\cdot10^{-9}$ to-$2\cdot10^{-8}$ cm${}^{-1}$ were measured with an accuracy of 30% and those in the range $3\cdot10^{-8}$ to $10^{-6}$ см${}^{-1}$ cm${}^{-1}$ with an accuracy of 10%. The detection threshold of the absorption lines was $10^{-9}$ cm${}^{-9}$.