Abstract

We present a system that measures the full-field amplitude and phase distributions of objects that vibrate with small amplitudes. The system is based on TV–holography combined with sinusoidal phase modulation, discrete vibration-phase shifts, and digital image processing. Different new algorithms, based on a linear approximation of the fringe function, are discussed. Averaging techniques, used to reduce the effects of noise sources and to increase the resolution of the system, are also introduced. For one of the algorithms, tested in combination with the averaging techniques, the amplitude threshold was approximately 1/3000 of the wavelength of the applied laser light. The amplitude resolution was of the same magnitude. The phase accuracy is amplitude dependent and was about 3° for amplitudes greater than 5 nm.

© 1992 Optical Society of America

Phasor-difference method for measuring the amplitude and the phase of small-amplitude vibrations with TV holography

Rolf Rustad
Appl. Opt. 37(23) 5386-5393 (1998)

Time-average TV holography for vibration fringe analysis

Upputuri Paul Kumar, Yanam Kalyani, Nandigana Krishna Mohan, and Mahendra Prasad Kothiyal
Appl. Opt. 48(16) 3094-3101 (2009)

Effect and use of exposure control in vibration analysis using TV holography

Geir O. Rosvold and Ole J. Løkberg
Appl. Opt. 32(5) 684-691 (1993)

Video-based vibration analysis using projected fringes

Geir Ove Rosvold
Appl. Opt. 33(5) 775-786 (1994)

Phase-stepped television holographic technique for measuring phase and amplitude maps of small vibrations

Henrik O. Saldner
Appl. Opt. 35(20) 3791-3798 (1996)