Patent ID: 8508591

Claim:
A method to estimate the height profile of an object, said method comprising: acquiring a plurality of raw images of an object to be characterized using at least one imaging device, where said plurality of raw images are representative of a plurality of spatial shifts between said at least one imaging device and said object to be characterized occurring parallel to a surface that the object to be characterized is resting upon; processing said plurality of raw images to generate a plurality of composite images, where each composite image of said plurality of composite images corresponds to a unique image shift between spatially adjacent raw images and is made up of a plurality of image pixel locations; calculating a volatility parameter value within a neighborhood of at least one same image pixel location of said plurality of image pixel locations for each of said plurality of composite images; determining which composite image of said plurality of composite images has a largest volatility parameter value for said at least one same image pixel location; transforming said unique image shift, corresponding to said composite image having said largest volatility parameter value, into a height value representative of a height dimension of said at least one same image pixel location; generating a height value for each image pixel location of said plurality of image pixel locations to form a height profile image of said object to be characterized; and comparing said height profile image to at least one reference image to find any defects in said object to be characterized.