本文提出一種三反射鏡消像差（Three-Mirror Anastigmat, TMA）成像儀的光學設計，適用於立方衛星（CubeSat）或一般衛星上的科學酬載，此設計的光學元件被限制在 0.8U 的體積範圍內，其中 1U 代表體積 10 x 10 x 10 cm^3，這體積範圍使該系統適用於小型的衛星架構。該儀器的主要科學目的是觀測電離層中的極光活動，並解析其細微結構，此系統解析度可達到 0.46km/pixel。本研究以台灣福爾摩沙衛星二號（FORMOSAT-2）上 ISUAL 光學儀器為基礎，利用Zemax模擬軟體進行光學設得的分析與優化。相較於 ISUAL 這類的穿透式光學系統，本論文設計的 TMA 光學系統可以更好的修正 Seidel 像差，此設計的調製轉換函數(MTF)在奈奎斯特頻率(Nyquist frequency)下有 0.78 的表現，光學畸變量為 1.2524 %，此結果顯示系統具備良好的成像品質以支援高解析度成像。

This paper presents an optical design of a Three-Mirror Anastigmat (TMA) imager for a scientific payload of a CubeSat or a standard satellite platform. The optical components are constrained to fit within a 0.8U volume, where 1U stands for 10 x 10 x 10 cm^3 volume, making the system suitable for compact satellites.The science goal of the instrument is primarily to observe the auroras in the ionosphere and capture their fine structures. This system can achieve a spatial resolution of approximately 0.46 km/pixel. This study takes the Imager of Sprites and Upper Atmospheric Lightning (ISUAL) onboard the FORMOSAT-2 satellite as a reference system. The optical design analysis and optimization were carried out using Ansys Zemax OpticStudio software. Compared with the refractive optical system, such as ISUAL, the TMA optical system can greatly correct the Seidel aberration. The designed system achieves a Modulation Transfer Function (MTF) of 0.78 at the Nyquist frequency. The system exhibits an optical distortion of 1.2524 %. These results indicate that the TMA system provides image quality suitable for high-resolution imaging applications.

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