大的热折射率系数和热膨胀系数使得染料激光介质的热效应远大于固体激光介质。对抽运时间内增益区液体介质的热效应进行研究,可以为更高功率液体激光器的设计研制和光束质量控制提供参考。根据流动液体能量方程,在抽运光功率由5.9 W增加至12.4 W时,理论计算了纵向抽运时间尺度染料激光器增益区温度场分布,并给出了由温度梯度而引起的信标光波前畸变。信标光的斯特雷尔比由0.9133下降至0.6174。应用波前曲率传感原理,实验测量了染料激光介质罗丹明6 G(Rh6G)乙醇溶液的热效应,采用理论计算相同的抽运功率条件下,增益区内参考光的斯特雷尔比由0.9464下降至0.4883,光束质量下降明显。

The big thermal refractive index coefficient and the thermal expansion coefficient make the thermal effect of liquid laser media greater than those of the solid laser media. Therefore,it is important to study thermal effects of liquid media in gain area during pumping time. According to the energy equation,the wavefront disfortion of the beacon beam induced by the temperature gradient is calculated theoretically in the longitudinal pumping geometry. When the pumping power is increased from 5.9 W to 12.4 W,the Strehl ratio of beacon beam drops from 0.9133 to 0.6174. With the application of wave-front curvature sensing theory,the thermal effect of Rh6G is studied experimentally. Under the same pumping condition with those of theoretical calculation,the Strehl ratio of beacon beam drops from 0.9133 to 0.6174. The beam quality becomes worse seriously.