输出镜反射相移对倍频效率的影响

利用Macleod反射相移理论,模拟V-型腔457 nm Nd:YVO4蓝光激光器输出镜多层膜反射相位偏移。结合I类匹配LBO倍频晶体的倍频特性,讨论了输出镜反射膜对腔内基光偏振特性造成的影响,及其对I类相位匹配倍频效率的影响。研究发现,当基频光在输出镜处,入射角不大于15° 的情况下,造成的反射相移小于2° 。在近似相位匹配下,倍频效率相对于理想情况降低幅度不超过6%。

Influence of the Reflection Retardence in Output Lens on Frequency-Doubling Efficiency

Reflection retardance induced by multi-optical coatings in output mirror of an all-solid-state single frequency V-shaped 457 nm Nd:YVO4 blue laser is reported with the theory of reflection-induced retardance by Macleod. Combining with the frequency-doubling theory of elliptical Gaussian beam under the conditions of critical phase matching, especially in type Ⅰ LiB3O5 (LBO) crystal, we discussed the influence the multi-optical coatings in output mirror on polarizing characteristic of intracavity fundamental frequency light and frequency-doubling efficiency. Research indicates that when the induced angle in output mirror is less than 15°, the refection-induced retardance is less than 2°. Furthermore, in the approximations of the exact phase matching, compared with the ideal case, the frequency-doubling efficiency reduced by multi-optical coatings is not more than 6%.