Research on Timing Compensation of Shadow Photograph System with Three-sequence Laser Sparking

The accuracy of the laser sparking time interval measurement plays a key role in the measurement results when the projectile velocity is measured by shadow photograph system with three-sequence laser sparking. By comparing with the original single-chip measurement results, it was found that there was a certain deviation in the measurement results of the laser sparking time. Then the principle of the laser sparking time measurement circuit is introduced in detail, and the reasons for this error phenomenon are summarized. And analyze the original laser sparking time measurement data column and the data column accurately measured with an oscilloscope, use the Pearson correlation coefficient to describe the correlation between the two data columns, and obtain the sample correlation coefficient, the first laser sparking interval coefficient r 1 =0.50, the second laser sparking interval coefficient r 2 =0.52. According to the three-level division rule, when 0.4≤|r|