It is a postulate in the test measuring speed of interference missile accurately.A diffuse reflection optical coupler velocity measurement system is introduced.The optical coupler is a sensor which is included emitter and receiver.When flying objects pass through the laser screen

the light is transformed by detector into electronic signal and sampled by data sampling card.Data processing is finished by professional software in computer.The structure and principle of velocity measurement system

drive circuit of optical coupler are introduced.The response velocity of optical coupler is surveyed.It gives the typical sampled waveform and a series of speed data of interference missile measured by the system.As a result

the velocity measurement method based on optical coupler has advantages of convenience in optic adjustment and high sensitivity.