原向反射式大面积三角形探测光幕灵敏度分布

Sensitivity distribution of large-area triangular detection light screen with original reflection

分体式大靶面测试系统的探测光幕灵敏度直接影响飞行弹丸速度测量的精度。可在散布不大的情况下,使用反射膜与激光器代替矩形大面积测试系统中的人工光源,简化测试系统。对新建的三角形探测光幕的灵敏度进行了分析,综合考虑激光器在不同传播距离处的光强度衰减、空间的非均匀性分布及反射膜逆反射系数和镜头离轴效应等因素,采用数值仿真和实弹试验的方法,将同一弹径的弹丸穿过光幕不同位置时的灵敏度等效到同一基准点进行归一化分析。结果显示,镜头离轴效应对灵敏度影响最大,激光器空间非均匀性分布影响最小。在3.5 m×2 m(宽×高)的直角三角形探测光幕区域进行实弹试验,其结果与仿真结果一致,距镜头越近,灵敏度越高;反之越低。研究结果可为类似原向反射式大面积探测光幕的工程设计提供参考。

The accuracy of the flying projectile speed measurement is directly affected by the detection light screen sensitivity of the split large-target test system. In the case of small dispersion, the artificial light source in the rectangular large-area test system can be replaced by a reflective film and a laser to simplify the test system. The sensitivity of the new triangular detection light screen was analyzed. The light intensity attenuation of lasers at different propagation distances, the non-uniform distribution in space, the retroreflection coefficient of the reflective film and the off-axis effect of the lens were taken into account. The sensitivity of projectiles of the same diameter through different positions of the light screen was analyzed by equivalent normalization at the same reference point by using numerical simulation and firing test. The simulation results show that the sensitivity is most affected by the lens off-axis effect and least by the non-uniform distribution of the laser space. The firing test was carried out in the right-angled triangle detection light screen area of 3.5 m×2 m(width×height). The results are consistent with the simulation results, the closer the lens, the higher the sensitivity, and the lower the versa. The results can provide a reference for the engineering design of a large-area detection light screen similar to the reflection type.