Frequency doubling of semiconductor lasers to generate 300-600 nm light

摘要

A novel control system for a simple and compact all-solid-state laser generating 300 nm to 600 nm nm light with continuously variable output power in the range from 1 mW to at least 120 mW. Single frequency radiation from an external cavity semiconductor laser is frequency doubled in, for example, a periodically poled MgO:LiNbO₃ ridge waveguide. Our laser maintains a high quality TEM₀₀ circular beam with M²<1.1 and a very low. noise of less than 0.06% over its range of output power. Less than 0.1% peak-to-peak output power variation is seen even during prolonged operation. In one example, no degradation of the conversion efficiency is observed for operation at an output power of 70 mW, and the laser has a small footprint of 5 cm.x8 cm.