Influence factors of Czerny-Turner edge band astigmatism correction
(2.Opto-electronics Engineer Institute,Changchun University of Science and Technology, Changchun ,China 130022)
【Abstract】To improve the weak correction capacity of a wide band Czerny-Turner structure, the influence factors on the astigmatism correction of an optical system were analyzed. The Matlab software was used to simulate and analyze the reasons that the astigmatism was produced and the traditional method could not suppress the astigmatism. Then, the dependence of the angle difference α between the off-axis angle of collimating mirror and the off-axis angle of focusing mirror on the astigmatism S of the optical system was discussed. The astigmatism correction of wide band Czerny-Turner structure was simulated at different α values. To verify the validity of the theoretical analysis, an astigmatic Czerny-Turner system ranging from 900 to 1 700 nm was designed, the Zemax was used to perform the ray tracing and optimal design and the design results were processed and analyzed. The simulation results demonstrate that the short-wave band astigmatism correction ability is getting stronger with increasing the angle difference, which may achieve about 1. 6 times on increase. However, long-wave band astigmatism correction ability is weaker and weaker, which may reduce about 1.27 times on average. It suggests that the reasonable selection of the angle difference can provide the theoretical guidance for correcting the astigmatism of wide band Czerny-Turner structures.
【Keywords】 optical design; Czerny-Turner structure; astigmatism correction; edge band;
(Translated by caizhijian)
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