Vibration parameter measurement using the temporal digital hologram sequence and windowed Fourier transform

Real time digital recording and numerical reconstruction of a temporal digital hologram sequence have become feasible in recent years. They provide a new measurement method which enjoys the valuable advantages of being full-field, noncontact and high precision. In this paper, a combined method of temporal digital hologram sequence and windowed Fourier transform is proposed to measure the kinematic parameters of random vibration. A series of holograms are recorded by CCD camera and the original phase can be reconstructed by Fresnel reconstruction algorithm. The three-dimensional windowed Fourier transform is used to filter noise in phase and extract the instantaneous kinematic parameters of the specimen, such as the displacement, velocity and acceleration. An experiment is conducted on a chloroprene rubber latex membrane. Results demonstrate that the proposed method determines the vibration parameters precisely and enjoys many merits.