China has developed a high accuracy four-meter-aperture optical mirror, an important tool for deep space and astronomical observation.

Developed by Changchun Institute of Optics, Fine Mechanics and Physics of the Chinese Academy of Sciences, it is the world's largest aspherical silicon carbide (SiC) optical mirror that measures 4.03 meters in diameter and 1.6 tons in weight.

The silicon carbide used in production provides more stability to the surface of the mirror, allowing for greater accuracy at 20 nanometers.

China owns all intellectual property rights of the core manufacturing equipment and techniques of the mirror, and it can be widely used in fields such as astronomical telescopes and spacecraft, marking that China currently has the world-leading state-of-the-art technologies of large-diameter SiC aspherical optical mirrors.

Europe and US have long held monopoly in the manufacturing technology of large diameter SiC optical mirrors, so China had to develop the techniques independently, said Zhang Xuejun, deputy director at the institute, also the person in charge of the project.

Experts said the successful development of the integrated manufacturing system of the mirror and the independent ability of R&D will be gradually applied to various types of large optical equipment.

In this way, China will leapfrog in the manufacturing technology of large-caliber optical mirrors and greatly improve the development of large high-performance optical instruments in the nation.

Zhang said four-meter SiC aspherical reflectors will be used in major national engineering projects. At the same time, the project will continue to be applied to a number of national major basic research and engineering projects, such as the multi-functional optical facility of China's space station, and other key national R&D programs.

(Top image: Researchers check the surface of a four-meter-aperture optical mirror. /VCG Photo)