Abstract. We present a design for a unit magnification imaging relay that is compact. The design uses two mirrors, and one is used by light twice for a three-reflection system. The mirrors are specified with freeform surfaces. There are several tradeoffs of performance depending on field of view, F / #, and wavelength range. One example provides a 30-mm circular field of view at F / 2.8, and another example provides a circular field of view of 40 mm in diameter at F / 4 for a length of ∼400 mm. Adding a third nearly flat mirror allows a system to provide a 50-mm field of view at F / 4 for a length of 420 mm. A last example includes a beam splitter cube to allow accessing the full field of view. These systems are diffraction limited at 550 nm.

中文翻译：

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使用自由曲面的紧凑型单位放大率反射式成像中继

摘要。我们提出了一种紧凑的单位放大率成像继电器的设计。该设计使用了两面镜子，其中一个被光使用两次，用于三反射系统。镜子指定为自由曲面。根据视场、F / # 和波长范围，性能有多种权衡。一个示例在 F / 2.8 下提供 30 毫米圆形视野，另一个示例在 F / 4 下提供直径为 40 毫米的圆形视野，长度约为 400 毫米。添加第三个近乎平面的镜子允许系统在 F / 4 下提供 50 毫米的视野，长度为 420 毫米。最后一个示例包括一个分束器立方体，以允许访问整个视野。这些系统的衍射限制在 550 nm。