Abstract
According to the interference theory of double-grating interferometers, the feature of Moiré fringe imaging in each region is investigated and a novel micro-displacement measuring method based on optical path modulation is proposed. The basic measurement principle is that the displacement is measured through Moiré fringe shifting, which is caused by the whole phased object thickness variation, in the case of non-relative movement of gratings. The object displacement measured can be changed into the phased object variation inserted in region II using a mechanical arrangement. The principle of the micro-displacement measurement is analyzed theoretically. The light intensity of the distributing image in each interference region is given no matter whether we insert the phased object or not. The effect on the Moiré fringe of the whole thickness variation of the phased object is also discussed. It is confirmed that the Moiré fringe shifts with phased object variation by calculation with MATLAB. The experimental result proves that the resolution of this method is 2.1093 μm, and the resolution of the system is 0.5273 μm after a four-subdivision circuit.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
