Noncontact method of point-to-point absolute distance measurement using tandem low-coherence interferometry

• Published in: Measurement science & technology Vol. 29; no. 2; pp. 25006 - 25013
• Main Authors: Winarno, Agustinus, Masuda, Shusei, Takahashi, Satoru, Matsumoto, Hirokazu, Takamasu, Kiyoshi
• Format: Journal Article
• Language: English
• Published: IOP Publishing 01.02.2018
• Subjects: absolute measurement; internal distance; tandem low-coherence interferometer; two points
• ISSN: 0957-0233; 1361-6501
• DOI: 10.1088/1361-6501/aaa16e

We propose a novel absolute measurement method for precisely measuring the internal distance between two points, using a tandem low-coherence interferometer. In this method, a beam splitter is positioned between two plane mirrors, the locations of which are accurately determined at the nanometre level using tandem low-coherence interferometry. Using a He-Ne laser interferometer as a reference length standard, an internal distance of up to 100 mm was measured remotely, with a measurement uncertainty of 178 nm (k  =  2).