考虑了二类非临界位相匹配晶体KTP对基频光的双折射效应及其倍频特点,将λ/4波片,λ/2波片和法拉第旋转器以适当方式组合起来,实现了激光器的单向运转.根据大功率光纤耦合激光二极管阵列端面抽运时激光晶体热效应的特点,设计了适当的谐振腔形.当抽运功率为10W时,得到了波长为540nm的1.0W单频绿光输出.自由运转情况下功率波动小于±1.5%,频率稳定性优于±5MHz,锁定后,频率稳定性优于±550kHz.

The characteristic of type Ⅱ noncritical phase matching and the thermal effect caused by high pump power are taken into account. An unidirectional operation is realized by using a λ/4 wave plate, a λ/2 wave plate and a Faraday rotator, and a proper cavity to reduce thermal distortion is designed. An intracavity frequency doubled Nd:YAP/KTP ring laser end pumped by an fiber coupled diode array with output power of 1.0 W at 540 nm is developed. In free running operation, the intensity fluctuation is less than ±1.5%, the frequency stability is better than ±5 MHz.