Infrared laser system, for cornea surgery, has a Q-switched laser-pumped short and-or heavily doped wavelength transformer for ultra-short pulse generation

摘要

A pulsed infrared (IR) laser system, comprises a Q-switched laser-pumped short and/or heavily doped wavelength transformer (2) for ultra-short pulse generation. An IR laser arrangement, for generating pulsed laser radiation of below 3 mu m wavelength, greater than 10 Hz pulse repetition frequency, less than 50 ns pulse length and about 100 mJ/cm<2> energy density, comprises a Q-switched pump laser (1) which generates light with less than 30 ns pulse length and greater than 10 Hz pulse repetition frequency and which has an emission wavelength in a region which corresponds directly or indirectly to a resonant transition in the uppermost laser level of an immediately following wavelength transformer (3) provided with a resonator system (2). The transformer material allows generation of laser pulses of less than 30 ns pulse length in the 3 /!0.3 mu m wavelength range. Light from the pump laser is axially coupled into the wavelength transformer by a resonator (21), such that the beam cross-section of the pump laser is matched to the mode volume of the wavelength transformer having a sufficiently short optically active length (L) and/or a sufficiently heavy doping, so that the absorption length of the pump laser radiation is 80-100% of the rod length.