摘要
本文详细地介绍了陕西天文台水平子午环的光电度盘测微器的数据采集系统和其定位归算原理。度盘被一个特殊设计的光学照明系统照亮,其刻线被光学放大系统成像于狭缝平面上。狭缝由计算机控制扫描这个刻线像,由于狭缝位置可精密地确定,利用透过狭缝光能量的变化可精密地确定度盘刻线的位置。光敏器件把透过狭缝的光变成光电流,放大后经模数转换变成数字量送往计算机。由于采集信号在理论上是严格的三角波,故用在顶峰前后各四点分别用最小二乘法确定波形的前后沿的直线方程,从而最终精密地确定波形顶峰的位置。由于测微器每次同时测定四根度盘刻线,因此有很高的定位精度。
This paper is concerened with data sampling system and Principles of data reduotion of photoeleotrie scanning micrometers on horizontal—meridian circle at Shaanxi Astronomical Observatory. While the division lines of the circle are lighted by illumination system of special design they are imaged on a slit plane by a optical system. The slit controlled by a computer scans the images of the division lines. Using the variation of the light energy is to determine the position of the division lines with very high accuracy since the light passed through the slit converts to the current by means of photocathode and is sent to the computer. Owing to be profile of a triangle shape in our sampling data related to time, the two straight lines, which are assigned to four Points before the peak point and four points after that, are determined by means of two least-squares solutions.Therefore, the positions of the peak points are determined.For our case that four division lines are determined in one measuring, we can obtain the positing of peak points with very high accuracy.
出处
《陕西天文台台刊》
CSCD
1989年第1期50-55,共6页
Publications of The Shaanxi Astronomical Observatiory
