“光栅玻璃不平行带来的误差”分析

Analysis for the Error due to the Non-parallel of the Grating Glass

由于光栅玻璃两表面不平行,给实验测量带来系统误差。通过计算,得到了光栅玻璃表面的四种不同夹角分别对应于在分光仪上的四种不同放置方式的系统误差。得出了这样的结果:在通常的实验所采用的波长和光栅常数情况下,一般光栅玻璃两表面不平行带来的误差低于分光仪度盘的最小读数值;在光栅玻璃两表面夹角较大时,以光栅刻痕面重直光轴并面对望远镜的情况,误差最小。

Because of the noni-parallel of the two surfaces of the grating glass,the systematic error is brought to the experimental measurement. Through computations, the anthors found the systematic errors of diverse cases :four different angles generated by the surfaces of the grating glass correspond to four setting positions on the spectrometer respectively. They get the results :under the constants of grating and the wave lengths that used in the usual experiments ,the error caused by the non-parallel of the two surfaces of grating glass is less than the smallest reading value of the spectrometer; if the angles generated by two surfaces of grating glass are larger,when the grating slits are perpendiculer to optical axis and are opposed to the telescope ,the error is least.