The optical frequency comb, which is a series of equidistant coherent optical lines in the frequency domain, has been greatly developed in the past two decades[1–3]. The conventional optical frequency comb is produced by the mode-locked laser and has played an important role in the precise measurement of time and frequency[4–6]. Based on the optical field enhancement of the microresonator, in 2007, the generation of the optical frequency comb was realized in the microresonator by continuous-wave (CW) laser pumping, which opens a new field of optical frequency combs based on the microresonator. Due to the emergence of noise in the generation process, the early microresonator frequency combs showed low coherence, and their application value was not expected. In recent years, with the discovery of dissipative Kerr solitons, stable and fully coherent soliton microcombs can be obtained in microresonators by simultaneously balancing gain and loss, as well as dispersion and nonlinearity[10–13].