For scanning systems the resolution, distortion as well as the telecentricity are important performance criteria. For two-dimensional scanning systems, scan mirrors deflecting in only one transverse direction are not allowing for telecentricity in x and y simultaneously in case of an axisymmetric system. It is possible to achieve two-dimensional telecentricity by splitting the pupils in x- and y-direction and shifting the principal planes in one dimension by changing the focal power using an anamorphic setup. However, for higher specifications concerning a large aperture and wide scanning angle, using cylindrical lenses are not enough to achieve a good system quality. It has been proved in many researches that freeform surfaces are effective to improve the resolution of systems without rotational symmetry. In this work, a systematic case study is presented to investigate the potential of freeform surfaces to improve the resolution, telecentricity, and distortion simultaneously. It is shown as a result that freeform surfaces offer large correction ability in all the three aspects concerning high specifications of 2D-telecentric anamorphic scan systems. This contribution provides the insight into the application of freeform surfaces in non-rotationally symmetric optical systems with refractive components.

中文翻译：

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具有自由曲面的2D远心扫描系统的校正。

对于扫描系统，分辨率，失真以及远心度是重要的性能标准。对于二维扫描系统，在轴对称系统的情况下，仅在一个横向方向上偏转的扫描镜不允许同时在x和y方向上进行远心定位。通过使用变形设置改变焦距，可以通过在x和y方向上分割光瞳并在一维上移动主平面来实现二维远心。然而，对于涉及大光圈和宽扫描角的更高规格，使用柱面透镜不足以实现良好的系统质量。在许多研究中已经证明，自由曲面可以有效地提高没有旋转对称性的系统的分辨率。在这项工作中 提出了一个系统的案例研究，以研究自由曲面的潜力，以同时提高分辨率，远心度和失真。结果表明，在涉及二维远心变形扫描系统高规格的所有三个方面，自由曲面提供了较大的校正能力。这一贡献使人们可以洞悉自由曲面在具有折射分量的非旋转对称光学系统中的应用。