Measurement of Solder Joint Deformation by Laser Speckle Correlation Techniques Rajamanickam Balamurugan*, Shanmugam Muruganand** *Department of Physics, Kumaraguru College of Technology, Coimbatore, Tamilnadu, India **Department of Electronics and Instrumentation, Bharathiar University, Coimbatore, India Online published on 2 August, 2016. Abstract In this paper, a non contact, non-destructive Laser speckle phase correlation and cross correlation techniques are used to measure small deformation of solder joint in the printed circuit board. Laser speckle images are recorded before and after deformation. Phase correlation technique is used for acquire the fringe pattern by subtracting these speckle images. This fringe pattern gives information on the subject of the deformation. Laser Speckle displacement can be assessed in terms of cross-correlation of speckle intensity peak deviation from the origin. Its height is lower than that of the autocorrelation and hence deformation is measured. Top Keywords Laser speckle, fringe pattern, cross-correlation, image processing, deformation. Top |