title: Method of vibration measurements in heterodyne interferometry.
abstract: A novel method is presented for determining the vibration amplitude of a vibrating fringe pattern in the presence of a low-frequency heterodyne phase shift. It consists of counting the average number of positive-going zero crossings, per vibration cycle, in the signal from a photodetector on which the moving fringes are imaged.
authors.forename: K A
authors.initials: KA
authors.lastname: Stetson