Introducing speckle noise maps for Laser Vibrometry
نویسندگان
چکیده
منابع مشابه
Numerical simulation of speckle noise in laser vibrometry.
The fundamental mechanism by which speckle noise is generated in laser vibrometry before describing a new numerical simulation for prediction of speckle noise level in a real measurement is considered. Factors within the simulation include rate of change of phase within individual speckle transitions, low-pass filtering to match the frequency range of experimental data with which comparison is ...
متن کاملA new method for filtering speckle noise in vibration signals measured by Laser Doppler Vibrometry for on-line quality control
Mechanical fault diagnostics for quality control of manufacturing appliances is often based on the analysis of machine vibrations. In the presence of mechanical faults, vibration signals comprise periodic impulses with a characteristic frequency corresponding to a particular defect. Vibrometers based on LDV (Laser Doppler Vibrometry) are an alternative to the traditional use of piezo-electric a...
متن کاملBayesian Spectrum Analysis for Laser Vibrometry Processing
Laser vibration sensing provides a sensitive non-contact means of measuring vibrations of objects. These measurements are used in industrial quality control and wear monitoring as well as the analysis of the vibrational characteristics of objects. In laser vibrometry, the surface motion is monitored by heterodyne laser Doppler velocimetry, and the received heterodyne signal is sampled to produc...
متن کاملNoise in laser speckle correlation and imaging techniques.
We study the noise of the intensity variance and of the intensity correlation and structure functions measured in light scattering from a random medium in the case when these quantities are obtained by averaging over a finite number N of pixels of a digital camera. We show that the noise scales as 1/N in all cases and that it is sensitive to correlations of signals corresponding to adjacent pix...
متن کاملLaser speckle imaging with an active noise reduction scheme.
We present an optical scheme to actively suppress statistical noise in Laser Speckle Imaging (LSI). This is achieved by illuminating the object surface through a diffuser. Slow rotation of the diffuser leads to statistically independent surface speckles on time scales that can be selected by the rotation speed. Active suppression of statistical noise is achieved by accumulating data over time. ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Optics and Lasers in Engineering
سال: 2009
ISSN: 0143-8166
DOI: 10.1016/j.optlaseng.2008.06.010