Condensation of the emission spectrum of a laser with a lens-like absorbing medium in the resonator

An investigation was made of the emission spectrum of a cw dye laser with an intracavity lens-like absorbing medium. The emission spectrum of the frequency-locked laser was obtained as a function of the oscillator strength of the absorption line and the resonator tuning, and measurements were also made of the selective reduction in the losses near the absorption line (10 ^{– 4}–10 ^{– 5} cm ^{– 1}). It was confirmed experimentally that the reason for the frequency locking of the laser radiation was a reduction in the diffraction losses in the resonator under the action of the lens-like properties of the absorbing medium.