Dome效应对四孔大气相干长度仪系统性能的影响

以水平方向距仪器1 000 m的卤钨灯为光源,通过同步对比实验探究了两台四孔大气相干长度仪的系统性能。实验结果表明,由它们测得的大气相干长度的大小和总体变化趋势能够较好吻合,相关性系数均在0.94以上,具有较好的一致性。在此基础上,进一步研究了Dome效应对该系统性能的影响。该效应的影响主要表现在使大气相干长度变小,其强度则由系统沿光路方向移动的距离决定。当移动距离小于15 cm时,Dome效应较弱,不会对实验结果产生明显影响;在距离从15 cm增至55 cm的过程中,其强度不断增加,并在55 cm处达到最强,此后则不再随距离的增加而变化。在整个实验过程中,实验结果的相关系数始终在0.9以上,即Dome效应对大气相干长度的总体变化趋势没有明显影响。

Influence of Dome effect on system performance of four-aperture coherent length monitors

System performances of two four-aperture coherent length monitors, whose optical source is tungsten-halogen lamp at horizontal direction, were explored by synchro contrast experiments. Experimental results show that, dimensions and temporal varying tendencies of atmospheric coherent length, measured by these two systems, are almost the same, and the correlation coefficients are all larger than 0.94. Influence of Dome effect on system performances was also researched. The main influence of this effect was embodied by the decreased of atmospheric coherent length, and the influence intensity was determined by the distance of the shifting system along the optical path. When the distance was smaller than 15 cm, there was no remarkable Dome effect. As the distance increased from 15 cm to 55 cm,