开展了一种红外和可见波段非线性光学性能测试研究。该研究基于二阶非线性光学原理,结合光电信号探测技术,提出了一种采用红外OPO激光以及把倍频光及其他光效应产生的光通过谱仪分光并结合CCD阵列探测器加以区分探测的新检测方案。主要解决了测试使用1064nm光源时,材料的倍频信号532nm被样品吸收后而探测不到倍频信号的缺点,以及准确测量了倍频信号强度,排除了其他光学效应产生的噪声干扰。其特点是采用1064和1905nm的双波长激光替代单一波长的激光源,该方案能适用于可见和红外非线性材料光学性能的测试。研究工作包括测试系统组成,工作原理和测试方法,并给出了采用本方法测试KTP,KDP,AGS以及几种新的红外非线性材料的实验结果,并且发现了几种有前途的非线性光学晶体材料。研究结果表明本方法具有稳定可靠、判别精度高、操作简单等优点,可以有效地定性或半定量测试材料的可见一红外非线性光学性能,为研究可见、红外乃至紫外二阶非线性光学材料提供重要的测试手段。
In the present paper the authors report a research on testing the nonlinear optical performance of op- tical materials in visible and infrared band. Based on the second order nonlinear optic principle and the photoe- lectric signal detection technology, the authors have proposed a new testing scheme in which a infrared OPO laser and a method for separating the beams arising from frequency matching and the light produced by other optical effects were used. The OPO laser is adopted as light source to avoid the error of measurement caused by absorption because the double frequency signal of the material is in the transmittance band Our research work includes testing system composition, operational principle and experimental method. The experimental results of KTP, KDP, AGS tested by this method were presented. In the experiment several new infrared non- linear materials were found. This method possesses the merits of good stability and reliability, high sensitivi- ty, simple operation and good reproducibility, which can effectively make qualitative and semi-quantitative test for optical material's nonlinear optical properties from visible to infrared. This work provides an important test method for the research on second order nonlinear optical materials in visible, infrared and ultraviolet bands.