用于二维线纹测量的二维动态光电显微镜

2-D Dynamic Photoelectric Microscope

对二维线纹标准样板进行溯源测量时,需要对十字刻线进行高分辨力瞄准。利用二维动态光电显微镜,将二维样板十字刻线分别成像在相互垂直的两组狭缝上,狭缝宽度与刻线像的宽度基本一致,方向与刻线像平行,且在像空间上沿宽度方向错开约一个狭缝宽度的距离。当二维线纹样板沿某一方向运动时,对应方向被测刻线的像先后呈现在一组狭缝中,导致通过该组狭缝的光通量依次发生变化,对应的两个光电接收器的电信号存在相位差;信号处理系统根据两路电信号的相位关系,在信号交叉位置发出瞄准脉冲,锁定坐标测量系统,即得到该方向被测刻线的位置;分别对十字交叉刻线的两条刻线进行瞄准,即可得到对应交叉点的坐标。

Traceable measurement of 2-D Line Scale templates needs high resolution aim at the crosswire. In the 2-D dynamic photoelectric microscope,the image of crosswire is illuminated on two sets of slits which are mutually perpendicular. There are two slits in each set,which have the same width with the image of crosswire. And the distance between the two slits in width direction is also the same size. When the template moves in one of the directions,the image of crosswire will appear in the two slits successively. The luminous flux of the slits will change one after another,which means there is a phase difference between the photoelectric receivers of corresponding slits. And the signal processing system judges the aiming moment using those two signal. In this way,2-D Dynamic Photoelectric Microscope can realize high resolution 2-D collimation.