Membrane diffractive optical elements formed by fabricating microstructures on the substrates have two important characteristics, ultra-light mass (surface mass density < 0.1 kg/m2) and loose surface shape tolerances (surface accuracy requirements are on the order of magnitude of centimeter). Large-aperture telescopes using a membrane diffractive optical element as the primary lens have super large aperture, light weight, and low cost at launch. In this paper, the research and development on space-based diffractive telescopes are classified and summarized. First, the imaging theory and the configuration of diffractive-optics telescopes are discussed. Then, the developments in diffractive telescopes are introduced. Finally, the development prospects for this technology used as a high-resolution space reconnaissance system in the future are summarized, and the critical and relevant work that China should carry out is put forward.

通过在基板上制造微结构而形成的膜衍射光学元件具有两个重要特性，即超轻质量（表面质量密度<0.1 kg / m2）和宽松的表面形状公差（表面精度要求在厘米量级上）。使用膜衍射光学元件作为主透镜的大口径望远镜具有超大光圈，重量轻且发射成本低的特点。本文对天基衍射望远镜的研究和发展进行了归纳和归纳。首先，讨论了衍射望远镜的成像原理和结构。然后介绍了衍射望远镜的发展。最后，