In order to verify whether the response time of 6 light screens is consistent while the projectile passing through the sky screens vertical target, and to improve the velocity measurement accuracy of test equipment，a measurement method for detecting the response time consistency of sky screens vertical target was proposed, and a test device based on this method of signal source for simulating projectile over-screen was designed. The device controls the two light source intervals to change lightly and darkly by digital-analog(DA) conversion, by calling the projectile contour data stored in the ROM, which is used to simulate the instantaneous change of light energy while projectile passing through the light screen. The test was completed by comparing the difference value between the time interval of two output signals collected synchronously by the signal acquisition and processing instrument with the delay time interval by the device. The test results show that the difference value between the output signal time and the set delay time is both less than 1 μs, which satisfies the technical requirements of the response time consistency of 6 light screens, the test device and the measurement method can be used for the measurement of response time consistency for the sky screens vertical target.