【摘要】 高精度平板的平面度一般用等厚干涉条纹测量,它的一个条纹间距相应于二分之一波长的光程差,用目测可以判别的平面度最高仅1/20波长,但是F-P干涉板要求1/100～1/200波长的平面度。本文描述了压电细分多光束干涉法,用压电陶瓷平移干涉板从而建立一组参考干涉条纹,设原相邻两条纹的距离为α,而参考条纹与原条纹的距离为α/m,用距离为α/m的条纹作基准目视或照相测量平面度,因此精度提高了m倍.在m=10时用目测方法可以探测到近1/200波长的误差。调节压电陶瓷的电压可方便连续地调节m,采用普通低频信号发生器产生的方波来驱动压电陶瓷。更多还原

【Abstract】 The flatness of a precise plane is generally measured by making use of fringes of equal thickness. The fringes contour interval is tantamount to 1/2 wavelength, the highest precision in measuring flatness by observation is about l/20 wavelength, but the plates used in F-P interferometer ought to be of flatness of 1/100-1/200 wavelength.A piezoelectric subdivision method of multiple-beam interference is described here, we form a group of reference fringes by translating the plate through a piezoelectric ceramic.The original gap between two adjecent fringes is supposed to be a, and the gap between the new reference fringe and original should be a/m. We test the flatness through observation or photography by making use of a/m as a standard, so we can gain in precision of flatness m times as high as the original. Supposed m=10, the method would be able to detect the error close to 1/200 wavelength with visual measuring. Adjusting the voltage of the piezoelectric ceramic then m can be continuously changed with ease, we use the square wave produced by a low frequency signal generator to drive the piozoelectric ceramie.更多还原