Organic dye laser with a retroreflecting mirror

An experimental investigation was made of the characteristics of formation of the radiation field of a laser utilizing a solution of rhodamine 6G in ethanol placed in a resonator with a retroreflecting mirror. Exchange lasing was observed and methods for suppressing it were studied. Compensation of static and dynamic optical inhomogeneities was achieved in the active medium of the laser and this reduced the angular divergence and increased the brightness of the output radiation by a factor of 25. The use of a retroreflecting mirror made it possible to dispense with thermal stabilization of the active medium.