The two critical specifications of a telescope system are the angular resolution (AR) and light collecting capacity (LCC). These specifications are closely related to the aperture of the system. AR is inversely proportional to the telescope's diameter, while LCC is proportional to its squared value. The larger the aperture, the higher and stronger the AR and LCC. Consequently, increasing the aperture becomes essential to improving the telescope's performance. That is why both astronomy and earth observing communities need large telescopes.

The larger size of the primary mirror in modern ground-based telescopes and space cameras imposes demanding and stringent requirements on mirror materials and full-spatial frequency (FSF) shape error control. Breakthroughs in mirror materials that support accurate and efficient manufacturing of large aspherical mirrors are urgently expected.

In a new paper published in Light: Science & Applications, a team of scientists led by Professor Xuejun Zhang from the Changchun Institute of Optics, Fine Mechanics and Physics have developed some new techniques for manufacturing large mirrors. Their paper, titled "Challenges and strategies in high-accuracy manufacturing of the world's largest SiC aspheric mirror," saw the team build its largest aspheric mirror.