Presently, an all-solid-state laser in this spectral range was obtained by frequency conversion, such as frequency-doubling, sum frequency, stimulated or Raman frequency-shifted.

目前，该波段的全固态激光光源主要是利用频率变换技术，通过倍频、和频、受激拉曼频移的方法来获得。

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The phase matching conditions for sum frequency generation are analyzed. The optimum phase matching angles and effective nonlinear coefficients for KTP and LBO are derived and calculated.

进行了双束激光和频相位匹配的理论分析，给出了KTP 和LBO 两种晶体在和频时的最佳相位匹配角和有效和频系数。

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The second step is to compute the cluster frequency for each cluster, which is the sum of all the rule frequencies within that cluster.

第二步是计算每个集群的集群频率，这是该集群中所有规则依赖关系的总和。

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