关键词: 激光技术, 脉冲展宽, 电光调Q, Nd:YAG激光器

Abstract:

Theoretical analysis about elements that influence pulse width of Q-switched laser has been carried out. Then, on the basis of rate equation, expressions of the relation among inversion density, photon density, and cavity loss under pulse stretching conditions were established. The cavity loss’s variation curve was plotted after numerical simulation for flat-topped laser pulse has been done. In the experiment, proper structure of resonant cavity was designed and, by taking advantage of two thyratrons as high-voltage switches, the variation of voltage on KD*P can be controlled, so the loss can be controlled to make it satisfy the pulse stretching conditions. Finally, 420ns Q-switched laser pulse was obtained.

Key words: laser techniques, pulse streching, electro-optical Q-switch, Nd:YAG laser