Laser diode-pumped monolithic solid state laser device for emitting single frequency laser beam, has Lyot filters permitting laser emission and having free spectral interval value equal to width of laser emission band of amplifier crystal

摘要

The device has two birefringent filters or Lyot filters in a resonant cavity permitting single frequency laser emission, where the Lyot filters are constituted from a polarizer (4) disposed in sandwich between birefringent crystals (5, 6). One of the Lyot filters possesses a free spectral interval value equal to a width of laser emission band of amplifier crystal (3). The other Lyot filter has a free spectral interval value different from the former value. Filter temperature control unit obtains a specific relation in the band with a phase difference of crystals to a base of filters.