High-speed picosecond laser is a device widely used in scientific research such as laser ranging, optical measurement, and the fluorescent lifetime analysis. In recent years, high-speed picosecond laser is further applied in the field of quantum cryptography, which becomes the core equipment generating quantum signal. WT-LD series laser is an inexpensive, ultra-narrow pulse, high stable optical equipment generative designed on the basis of quantum cryptography communication system. By combining the continuous laser with ultra narrow high-frequency pulsed laser, it is a high-performance picosecond laser that can realize 1/1.25GHz pulse in the world. The equipment has rich functions that can work in internal/external trigger mode. Users can choose input signals of various reference levels conveniently and visually through human-computer interface, as well as adjust each of the important parameters the laser output.