Abstract: A solid-state laser or arrangement for wavelength conversion is disclosed, which in its simplest embodiment is comprised of a light-generating body arranged in a supporting means, the light-generating body having a shape which is substantially complementary to a guiding structure which is formed in the supporting means. The guiding structure is formed with a high degree of accuracy, for instance, by etching the supporting means or by replicating an original. Between the light-generating body and the guiding structure of the supporting means a thin contact layer is arranged, the purpose of which is to increase the adherence to and/or the heat transfer to the supporting means. Due to the fact that the contact layer is a deformable material, possible discrepancies as regards complementary between the guiding structure and the light-generating body will be filled by the contact layer whereby a close fit is obtained between the complementary structure.