基于材料补偿的线性色散组合棱镜研究

Study of Compound Prisms with Linear Dispersion Based on Material Compensation

作为传统的分光器件,棱镜的非线性色散缺陷限制了其在精密光谱仪器中的应用。从分析棱镜非线性色散产生的本质出发,建立了材料的色散模型,提出了一种线性色散组合棱镜设计方法。使用非线性系数T_1和T_2相近、线性系数V相异的两种材料,通过控制组合棱镜的参数和光线入射角可获得线性色散。最后通过建立线性色散组合棱镜的评价指标,对设计结果进行了科学、合理的评价,验证了设计理论的正确性。研究发现,组合棱镜能够有效改善棱镜的非线性色散缺陷,其改善程度依赖于两种材料的绝对非线性系数P。当P<0.01时,组合棱镜可获得线性色散,其色散曲线的非线性(Nonlinear,NL)优于5%。

As a kind of traditional optical components, prisms are limited in the application of modernoptical instruments because of their nonlinear dispersion. By analyzing the dispersion nature of prisms, a dispersion model of material was established and a design method of compound prisms with linear dispersion was proposed. Two kinds of materials with close nonlinear dispersion coefficients T／ and T2 and different linear dispersion coefficient V were used. By controlling the parameters of the compound prism and the incident angle, linear dispersion could be achieved. Finally, the evaluation index was established for the linear dispersion compound prism. The designed result was evaluated scientifically and reasonably. The correctness of the design theory was verified. It was found that the nonlinear dispersion of the compound prism was improved effectively. The improvement of nonlinear dispersion was dependent on the absolute nonlinear coefficient P of two kinds of materials. When P was greater than 0.01, the compound prism could achieve linear dispersion. The nonlinear （NL） of the dispersion curve was better than 5%.