The design and construction of a laser interferometer using the method of exact fractions for high-accuracy calibration of gauge blocks up to about one meter in length, are described. The interferometer is based on the classical Michelson arrangement. A two-mode stabilized He-Ne laser emitting light at a wavelength of 633 nm is the primary wavelength reference for the interferometric length measurement, since its frequency is calibrated by heterodyne measurement with an iodine-stabilized He-Ne laser at 633 nm which is used to maintain the national meter standard. A second two-mode stabilized He-Ne laser, at a wavelength of 543 nm, is used in order define the absolute length. The estimated standard uncertainty for interferometric length measurements is about 50 nm for a 1 meter gauge block. Results from trial measurements made on various gauge blocks, including a bilateral comparison, are reported.

Date Published: 30 September 1998
PDF: 10 pages
Proc. SPIE 3477, Recent Developments in Optical Gauge Block Metrology, (30 September 1998); doi: 10.1117/12.323122

Published in SPIE Proceedings Vol. 3477:
Recent Developments in Optical Gauge Block Metrology
Jennifer E. Decker; Nicholas Brown, Editor(s)