Abstract

We describe a new method for real-time detection and measurement of small vibrations, based on phase modulation in time-average electronic speckle pattern interferometry. The modulation frequency is shifted relative to the vibration frequency, which makes the intensity of the reconstructed image vary at the difference frequency. The amplitude detection limits are about 20 Å by visual observation and 0.1 Å by photoelectric measurement using a lockin technique. No auxiliary system for fringe stabilization is required. At higher amplitude levels we can study the deformation of the object in slow motion. Measurements on different objects, including human ear preparation, are presented.

© 1977 Optical Society of America

Measurement of small vibrations using electronic speckle pattern interferometry: Theory

Kåre Høgmoen and Hans M. Pedersen
J. Opt. Soc. Am. 67(11) 1578-1583 (1977)

Vibration phase mapping using electronic speckle pattern interferometry

Ole J. Løkberg and Kåre Høgmoen
Appl. Opt. 15(11) 2701-2704 (1976)

Vibration measurement by the time-averaged electronic speckle pattern interferometry methods

Wei-Chung Wang, Chi-Hung Hwang, and Shu-Yu Lin
Appl. Opt. 35(22) 4502-4509 (1996)

Vibration measurement using phase-shifting speckle-pattern interferometry

Suezou Nakadate
Appl. Opt. 25(22) 4162-4167 (1986)

Vibration of flutes studied by electronic speckle pattern interferometry

Ole J. Løkberg and Ola K. Ledang
Appl. Opt. 23(18) 3052-3056 (1984)