Using large-aperture telescopes to observe celestial objects can yield high-resolution images. However, the larger the telescope aperture, the more significant the impact of system and environmental factors becomes. For example, the rotation of the mirror can cause deformation due to changes in gravity, and temperature changes can cause thermal expansion and contraction of the mirror and mechanical structures, all of which can degrade the imaging quality of the telescope. To eliminate these effects, people have come up with various solutions, such as using low-expansion mirror materials, adopting floating mirror support systems, and employing cutting-edge processing technologies. These can to some extent offset the effects of environmental changes, but they are merely "passive prevention" rather than "active improvement." Later, astronomers proposed the concept of active optics. Compared with traditional "passive optics," active optics aims to actively overcome the deformation of the telescope mirror during operation through mechanical and optical means, thereby improving the imaging quality of the telescope. Currently, there are two main types of active optics technologies: one is called spliced mirror active optics, where each small mirror of the spliced mirror is independent and can be used to correct the imaging by changing its position and tilt angle in real time; the other is called thin mirror active optics, where when the mirror is very thin, the curvature of the mirror can be changed in real time by applying pressure, thereby achieving the purpose of improving the imaging quality.
In addition to their large apertures, large astronomical telescopes also have large instruments and equipment such as spectrometers at the back end. These large instruments, when mounted on the telescope, place a heavy burden on the telescope and the gravity deformation caused by the rotation of the telescope also affects the measurement accuracy. How to solve this problem? In the past, people used a set of "folding optical paths" to direct the light to fixed large instruments, but the additional optical system would inevitably reduce the observation efficiency of the telescope. Therefore, people turned their attention to optical fibers - optical fibers can direct the light to any location near the telescope with minimal energy loss. The connection problem between large instruments and telescopes was thus solved. In addition, optical fibers can also be used for multi-target observation. If there are 100 stars in the field of view of the telescope, the starlight can be directed to large equipment for analysis using 100 optical fibers, greatly improving the observation efficiency.