给出了单轴晶体ooe,oeo,eoo,eeo,eoe,oee 6种相位匹配方式相位匹配角的解析公式。其中ooe,oeo,eoo 3种可以计算共线及非共线情况,eeo,eoe,oee 3种只能计算共线情况,非共线情况需数值求解,给出了数值求解的方法步骤。研究了双轴晶体折射率在主平面时与单轴晶体折射率的对应关系,利用该对应关系,通过替换折射率的方式求解双轴晶体的相位匹配角度。给出了常见晶体的非共线相位匹配角度图,以供科研人员参考。
ooe, oeo, eoo, eeo, eoe and oee types phase matching angle calculation formulas in uniaxial crystals are provided. The formulas used for ooe, oeo and eoo types can be applied to both collinear and non-collinear configurations. The formulas used for eeo, eoe, and oee only can be applied to collinear configuration. The numerical methods are provided for non-collinear configuration for eeo, eoe and oee types. The relationship of refractive index between uniaxial crystal and biaxial crystal in principal plane is given. Using this relationship,one can use the method for uniaxial crystal to calculate the phase matching angle in biaxial crystals through replacing the refractive index. The phase matching angles in some common nonlinear crystals are calculated for researchers′ reference.