天文学以科学为导向、观测为基础、发现为驱动。大天区面积高精度多波段成像测光巡天已成为发现和探索新天体、新现象，深入研究各类天体性质及其形成和演化的最重要的天文学研究手段。至今为止，所有国内外的大视场巡天计划均只能在同一时间对观测天区进行单一波段成像，无法获取天体的实时颜色信息。因此，基于这些巡天“拍摄”的天体运动、变化的影像仅仅是“黑白影片”或“伪彩色影片”。开展变源、暂现源研究的瓶颈在于获取高精度的实时颜色信息以对其各类候选体进行快速分类与证认，而现有的巡天均无法有效解决该难题。云南大学“多通道测光（梦飞）巡天望远镜”（Multi-channel Photometric Survey Telescope，简称Mephisto）通过创新性的光学设计，在国际上首次实现较大通光口径、较大视场、多通道高精度测光巡天。

Large-scale astronomical surveys play a crucial role in modern astrophysical studies, leading to new discoveries and revolutionizing our understanding of the origin and evolution of the universe. The fast technological advances are changing the ways we view the sky, from snapshot taking in surveys such as SDSS and XSTPS-GAC, to movie shooting by observing the same sky thousands of times in surveys, such as ZTF, Skymapper, WFST, and LSST. The developments open up the possibility of probing the universe in multi-dimensions, particularly in time domain. Considering upon the experiences of those surveys and to make a step forward, we are building a wide-field multi-channel survey telescope -- the Multi-channel Photometric Survey Telescope (Mephisto), the first of this type in the world.

梦飞巡天望远镜是一台较大通光口径（1.6米）、较大视场（3.14平方度）的多通道测光巡天望远镜。其创新性地采用了加改正镜的Ritchey-Chretien（RC）系统与立方分色棱镜，使望远镜焦面在主镜之下，且焦面与主镜之间有较大的距离，从而能在后端光路安置分色系统及多台相机，同时保证了整个视场上的优质像质。梦飞巡天望远镜将配备三台CCD相机，总像素高达10亿，能同时在三个波段（ugi或vrz）对同一天区进行高质量成像测光观测，获取高精度的实时颜色信息，“录制”宇宙天体运动和变化的“彩色记录片”。梦飞巡天望远镜的三通道设计不仅显著提高了巡天的效率和颜色定标精度，更重要的是通过提供高精度的实时颜色信息，有效地解决了变源与暂现源研究面临的瓶颈。高精度的颜色信息对获取恒星的一系列重要物理参数（如温度、金属丰度、距离、年龄等）也具有极为重要的意义。梦飞巡天望远镜项目于2018年1月立项，在各方的大力支持下，项目按计划实施，进展顺利。2021年6月完成台址建设。2022年9月，梦飞巡天望远镜（小系统）开始在站安装并在2022年10月23日实现初光，取得良好像质。望远镜现搭载2台科学级超大靶面单芯片相机，覆盖 1/4 视场，已具备很强的观测能力。望远镜目前处于调试阶段，对标准星（场）、多个变源暂现源（超新星、潮汐瓦解事件候选体、AGN、变星等）进行多历元多波段同时观测，已开展多个国际合作和科学研究工作，产出有用的观测数据并获得重要科学成果，即将启动为期一年的先导巡天。

Mephisto has a 1.6 m primary and is equipped with three CCD cameras of a field-of-view 3.14 sq deg, capable of simultaneously imaging the same patch of sky in three bands (ugi or vrz). The three cameras boast a total of 1.0 gigapixels. Mephisto can yield real-time colours of astronomical objects with unprecedented accuracies and deliver for the first time a coloured documentary of our evolving universe. The Mephisto project was initiated in January 2018. With strong support from all funding agencies, the project was implemented as planned and progressed smoothly. The site construction was completed in June 2021. In September 2022, the Mephisto telescope (equipped with 3 small cubic prisms, dubbed as ‘small system’) began the on-site installation and assemblage and achieved its first light on 23 October 2022. The telescope is currently equipped with two Andor iKon-XXL single-chip cameras, covering 1/4 of the field of view, and has strong observational capabilities. Now, the project is under the commissioning phase. Since the first light, we have conducted multi-epoch and multi-band simultaneous observations of standard stars (fields) and different transients (including supernovae, tidal disruption event candidates, AGNs, variables, etc.). International cooperation and scientific researches have been carried out, collecting valuable observation data and achieving important scientific results. A one-year pilot survey is scheduled to be carried out soon.