US Patent 8000363 Solid state laser device with reduced temperature dependence

The present invention relates to a solid state laser device with a solid state gain medium between two resonator end mirrors (3, 5) and a GaN-based pump laser (1) arranged to optically pump the solid state gain medium. The solid state gain medium is a Pr3+-doped crystalline or polycrystalline host material (4) which has a cubic crystalline structure and highest phonon energies of ≦600 cm−1 and provides a band gap of ≧5.5 eV. The proposed solid state laser can be designed to emit at several visible wavelengths with the emitted power showing a reduced dependence on the temperature of the GaN-based pump laser (1).