Abstract One of the key tasks in designing off-axis optical systems is to place freeform surfaces in optimal locations. By analyzing the real ray paths, we introduce one simple method for locating freeform surfaces in off-axis systems. A four mirror off-axis microscope objective with freeform surfaces is designed to demonstrate the method, the result shows that our method is effective in identifying the optimal locations of freeform surfaces.

中文翻译：

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为离轴光学系统定位最佳自由曲面

摘要 设计离轴光学系统的关键任务之一是将自由曲面放置在最佳位置。通过分析真实的光线路径，我们介绍了一种在离轴系统中定位自由曲面的简单方法。设计了一个具有自由曲面的四镜离轴显微镜物镜来演示该方法，结果表明我们的方法在确定自由曲面的最佳位置方面是有效的。