在铌酸锂晶体非共线相位匹配太赫兹波参量振荡器中观察到了级联光学参量效应。实验中测量到了一阶、二阶和三阶斯托克斯光。通过分析一阶、二阶和三阶斯托克斯光谱发现相邻阶斯托克斯光频率差相等,表明在太赫兹波的产生过程中发生了级联光学参量效应。在高阶级联光学参量过程中,一个泵浦光子可以产生多个太赫兹光子,表明在太赫兹波产生过程中量子转换效率会有效提高。 Cascaded optical parametric effects were observed in non-colinear phase-matched terahertz-wave parametric oscillators of lithium niobate crystals. First-order, second-order and third-order Stokes light were measured. By analyzing the first order, second order and third order Stokes spectra, it is found that the adjacent Stokes light has the same frequency difference, indicating that cascade optical parametric effect occurs during the generation of terahertz wave. In the high-order cascade of optical parameters, a pump photon can generate multiple terahertz photons, indicating that quantum efficiency can be effectively increased during terahertz wave generation.