Open AccessMeasuring parallelism of two parallel narrow beams based on differential defocusing principle
Author(s) -
Zhengang Lu,
Miaomiao Li,
Tao Zheng,
Lei Wang,
Jiubin Tan
Publication year - 2016
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.24.015854
Subject(s) - optics , collimated light , parallelism (grammar) , cardinal point , physics , differential (mechanical device) , plane (geometry) , lens (geology) , noise (video) , beam (structure) , ptychography , computer science , image (mathematics) , diffraction , artificial intelligence , laser , mathematics , geometry , parallel computing , thermodynamics
We present a method of measuring the parallelism of two parallel narrow beams by positioning a CCD each before and after the focal plane of the collimation lens. Because of this differential defocused positioning of the two CCDs, the two beam spots cannot overlap on the CCD image plane even if they are nearly parallel, and the distance between the two spots on each CCD can be obtained simultaneously, which eliminates the influence of environmental noise. Our experimental results show that a satisfactory system stability and resolution of 0.1″ and 0.2″, respectively, can be obtained with the proposed method.