The present disclosure provides a narrow-pulse-width pulse laser, including a circuit substrate, a laser chip, one or more capacitors, and a field effect transistor. Each of the field effect transistor, the capacitor, and the laser chip is electrically connected to the circuit substrate. The capacitors are arranged between the field effect transistor and the laser chip along an extension direction of a gap between the field effect transistor and the laser chip. The circuit substrate may include a first conductor layer; a second conductor layer; and an insulating layer arranged between the first conductor layer and the second conductor layer, wherein the first conductor layer and the second conductor layer are electrically connected through a via hole in the insulating layer.