Use of a three-mirror resonator of special configuration in a dye laser

A description is given of a tunable dye laser with a grazing-incidence grating and a three-mirror resonator, operating near its stability limit, which made it possible to increase considerably the size of the TEM₀₀ mode. Conversion of 10% of the pump was achieved and the width of the emission line was 0.1 cm^–1.