场转动环形非稳腔的空间平均效应研究

摘要

将光束绕光轴旋转的思想应用于改善固体激光谐振腔失调,增益不均匀,泵浦热效应等问题.设计了束转动环形非稳固体激光腔.采用快速傅里叶变换的方法,对束转动环形非稳腔的空间平均效应进行了数值模拟,发现对于固体激光器不同的泵浦方式,光束旋转产生的空间平均效应不同,其效果与光束旋转特点、泵浦方式、腔的放大率、束转动角度等有关.本文对几种不同形式的增益不均匀进行计算,对于增益介质横截面一维方向不均匀和角向不均匀的情况,束转动90°环形非稳腔能有效补偿空间不均匀.得到的结论为束转动90°环形非稳腔的优化设计和应用提供理论依据.%The idea of rotating the beam around the optical axis is applied in the solid laser resonator to improve mismatching, uneven gain, pump thermal effects and other issues.An unstable ring resonator with beam rotation has been designed.Using fast Fourier transform method, the mode of unstable ring resonator with beam rotation is simulated.It is shown that the compensation effect to uneven factors is different for different pump styles.The average effect of beam rotation is related to the characteristics of the beam rotation, pumping, cavity magnification, beam rotation angle and so on.In this paper, the average effect of beam rotation is compared for several different pumping styles.As to compensating the inhomogeneous gain, it is found that the beam rotation is favorable when the cross-section is uneven at one-dimensional and angular orientation.The conclusion lays the theoretical foundation for designing and application of unstable ring resonator with 90°beam rotation.