Powerful single-frequency laser system based on a Cu-laser-pumped dye laser

摘要

Reported are the results of development, prototyping and investigation of a powerful laser system based on a frequency-stabilized dye jet laser pumped with a copper vapor laser. Short- and long-term frequency instability of the system is approximately $POM@50 MHz at output power 4.5 W in the 610 - 620 nm spectrum range. In case two amplification stages are used, the overall efficiency of the system is higher than 15%. It can be further bettered by raising the pump power of the output stage. The region of smooth output frequency tuning of the stabilized master oscillator is as wide as 8 GHz, while maintaining the scanning rate of up to 1 GHz/sec. The system allows pumping of the master oscillator as well as amplifiers with either open beam of a copper laser or by way of fiber delivery. When pumping the master oscillator through a fiber, for the first time we focused the radiation at the exit of the fiber by means of a modified Fraunhofer objective lens. This type of optical system creates the focal spot twice as small as the fiber diameter while maintaining minimum spherical aberrations.