Recently, the State Timed Center Zhang led the first quantum frequency standard research team in optical standard research has made important progress. The team strontium light clock research group under the guidance of Professor Chang Hong, through the direct optical comb (optical comb) mode selection and amplification, the successful production of a single-mode narrow-line laser light source through the optical comb, and applied to Strontium optical clock device system to achieve a narrow linewidth strontium atomic cooling and clock frequency measurement. The research was published in the article entitled "Selection and amplification of a single optical frequency comb mode for laser cooling of the strontium atoms in an optical clock", Applied Physics Letters, Top Journal of the American Physical Society (Appl. Phys. Lett. 107 , 151104 (2015)). The first author of the article is PhD student Liu Hui. Strontium light clock is the highest accuracy and stability of the world's optical frequency standard, the development usually requires six different wavelength laser light source, the system is complex and huge. By using this method and technology, it is possible to use only one set of light combs to generate all the light sources of the strontium light clock and greatly simplify the strontium light clock system, which is particularly suitable for the development of the space light clock. The research has been supported by the National Natural Science Foundation of China major instrument project "a new generation of time and frequency system" and the face of the project "two-electron atomic coherence and its application in optical frequency standard".