title: Simple method for reducing the first-order optical nonlinearity in a heterodyne laser interferometer.
abstract: A simple method was proposed by using a tunable attenuator fitted in the reference or measurement arm of a heterodyne laser interferometer to adjust the values of mixing laser beams while the spectrum of the measurement signal is monitored using a signal analyzer. The effectiveness of the proposed method in reducing the first-order optical nonlinearity was verified through experiments. Results indicated that the peak value of the first-order optical nonlinearity could be reduced from 5.15 to 0.24 nm. It was therefore concluded that the proposed method was applicable to ultraprecision laser interferometry.
authors.forename: Haijin
authors.initials: H
authors.lastname: Fu
authors.forename: Pengcheng
authors.initials: P
authors.lastname: Hu
authors.forename: Jiubin
authors.initials: J
authors.lastname: Tan
authors.forename: Zhigang
authors.initials: Z
authors.lastname: Fan