The exploration of the galaxy is endless, and we are committed to creating a "sky-asking tool"

The universe is vast, and it requires the cooperation of all mankind to explore its mysteries. Talking about the development of China's astronomical exploration, it can be said that we are proud and regretful. As early as the Han Dynasty, my country had established an astronomical institution similar to today's observatory, the Sitianjian. While setting up instruments such as the armillary sphere, it appointed special officials to be responsible for observation, calendar calculation, education and other work, thus becoming the country with the longest observation history in the world. But it is regrettable that since when, my country's research and development speed for the research and development of large-aperture telescopes, which are essential "weapons" for astronomers, has gradually fallen behind the world mainstream. At that time, no matter how clever the astronomers were, they could not "cook without rice". This is why the completion of the Guo Shoujing Telescope (LAMOST) makes Chinese astronomers so excited, and it is also the original intention of An Qichang, an associate researcher at the Changchun Institute of Optics, Fine Mechanics and Physics of the Chinese Academy of Sciences (referred to as "Changchun Institute of Optics, Fine Mechanics and Physics"), to devote himself to the cradle of optical talents in my country. "Like countless predecessors, I want to do my best to mark the new heights of our country's deep space exploration in the boundless sky," he said.

▲An Qichang

In 2009, An Qichang first learned about scientific research through participating in micro-nano mechanics-related research projects, and then began to think about devoting himself to scientific research. Two years later, the vigorous spirit of "challenging optical precision instruments" was taken up by the Wang Daheng Opto-Mechanical and Electrical Technology Talent Class of Changchun Institute of Optics, Fine Mechanics and Physics. In An Qichang's perspective, the people here have been continuing the excellent scientific research quality left by their predecessors, striving to tell the infinite mysteries and profound philosophy hidden in the universe. Therefore, bathing under the starry sky, he felt that he had found his home, and slowly took on the relevant research work of "optical detection" on his shoulders.

The 2021 National Natural Science Foundation Youth Project "Research on the Mechanism of Improving the Curvature Sensing Accuracy of Large-Aperture and Large-Field Active Optical Photographic Survey Telescopes Based on Multiple Defocus Locking Distances" and the 2024 National Natural Science Foundation General Project "Wavefront Aberration Perception and Control Mechanism of Multi-Mirror Large-Aperture and Large-Field Optical Survey Telescopes" are excellent proofs of An Qichang's courage to take the lead and climb the peak of science and technology. In the project, he twice anchored the large-aperture and large-field active optical photography survey telescope as the research object, and gradually improved its wavefront sensing accuracy and the ability to maintain the surface shape and posture of optical components to meet the future astronomy's needs for detection breadth, depth and time dimensions.

Based on the multiple defocused distance-locked curvature sensing architecture, An Qichang tackled the two scientific problems of "the influence of discrete boundaries on detection accuracy" and "quantitative description of the influence of multiple defocus errors on wavefront sensing accuracy" two years ago. He and his team used spatial frequency domain analysis methods to establish the correspondence between the intensity of each region of the multiple defocused image and the wavefront phase, revealing the quantitative relationship between the distance-locked error and the solution accuracy. With the analytical expression of the error impact as the main line, they finally achieved single-exposure, high-precision curvature sensing, laying a solid foundation for the development of my country's future 8-12 meter photographic survey telescope. Now, An Qichang said that as new scientific research projects are in full swing, they will clarify the three key scientific issues of "multi-path perception and reduction characterization mechanism of full-field non-narrowband wavefront aberrations", "common benchmark measurement mechanism of precision coverage boundary of internal and external composite measurement system", and "influence of random wavefront aberration components on multi-mirror control feedback" on the basis of clarifying the laws of multi-band and multi-mode aberrations. Starting from the three major directions of "perception-benchmark-control", they will construct a new system for wavefront aberration perception and control of large-aperture and large-field-of-view optical systems, so as to give new vitality to the "Wentian" weapon.

Deep space exploration is like chasing stars in the dark night. Generation after generation of scientists have been determined to do this and have spent their lives exploring. It is an extremely pure and simple journey, but also an extremely glorious and romantic journey. At present, An Qichang has not stopped his pace, and is further discussing with his team the use of astronomical photonics interconnection technology to design a comprehensive test system for large-aperture telescopes to improve the quality and accuracy of observation data. He knows that as a young scholar, the road ahead will still be long, but the exploration of the galaxy is endless, and his own efforts should also be endless.