Abstract: A frequency-doubled diode pumped solid state laser with intracavity frequency doubling comprises a lasing solid state medium with suitable reflecting coats which makes up a component part of a resonator cavity. The solid state laser further comprises at least one pumped light source constructed as a laser diode and a frequency doubling nonlinear optical element in the form of a nonlinear crystal with suitable reflective coatings which forms a further component part of the resonator cavity. This resonator cavity is formed between reflective coatings of the solid state medium and of the element. The pumped radiation is transmitted to the lasing solid state medium through optical means. At least one aperture of a material with good thermal conductivity is provided at the element and/or at the lasing solid state medium. The frequency doubling optical element is designed for phase matching at a higher temperature than the surrounding temperature.

Abstract: Mode-locked laser comprising an active medium for the emission of a fundatal frequency radiation w1, with a resonator which is defined by a first mirror and a second mirror and in which the active medium is disposed, and a nonlinear optical means which is arranged between the active medium and the second mirror and which in combination with the second mirror effects a preferred reflection of radiation of higher intensity compared with radiation of lower intensity and it converts a fundamental-frequency radiation reversibly into radiation of a first frequency and radiation of a second frequency in such a manner that with increasing intensity the fraction of the radiation of the second frequency increases, and that the second mirror reflects at the second frequency to a greater extent than at the first frequency.