LD Direct Pumping Nd:YAG Intracavity Frequency Doubling660nm Red Laser

We studied the Nd:YAG crystal as the laser gain medium,885nm semiconductor laser diode directly pumped at the laser output characteristics in this paper. Through the rational designed of the laser cavity, and the1319nm laser output was obtained, ultimately through the nonlinear frequency-doubling crystal LBO obtained660nm red continuous output, compared for the output characteristics of808nm pumping.We conducted in-depth research, specific works are as follows:1. Analysis of thermal effects on the crystal quality of the laser beam and the basic principles of its formation, research the direct pumping of the crystal can reduce the thermal effects of reasons;2. From theory of nonlinear frequency conversion to start, introduced the theory of nonlinear frequency conversion, from the main constitution of the internal, optical properties, matching parameters etc, compared three kinds of non-linear transformation crystal BIBO, KTP and LBO and final selected Frequency-doubling crystal used in the experiment;3. Starting from four-level rate equation, theoretical analysis to the directly pumped solid-state lasers, calculated the laser output characteristics, such as the threshold power and slope efficiency of the relations. Designed a laser resonator, and simulated the changes of resonant cavity with the thermal lens focal length, proved the direct pumping can better be able to increased laser slope efficiency and reduce the threshold power, improved beam quality;4. We use the885nm pump laser directly pumped Nd:YAG laser, and compared the experiments of808nm indirectly pumping Nd:YAG laser, obtained experimental results are consistent with the theoretical derivation of the results obtained, further proof of the direct pumping slope in terms of improving the slope efficiency and reduce effect of the heat to be better than the indirect pumping.