High-resolution ultrafast 3D imaging

A novel high-speed 3D imaging system, base don projecting a speckle pattern onto an object and imaging the resulting pattern from multiple angles, is proposed that uses a unique single lens camera system with a rotating off-axis aperture. The rotating aperture allows adjustable non-equilateral spacing between defocused images to achieve greater depth of field and higher sub-pixel displacement accuracy. High resolution ultra fast processing is achieved by recursively correlating image pairs down to diffraction limited image size of the optics. Correlation errors are eliminated during processing by a novel technique based on the multiplication of correlation table elements from one or more adjacent regions. The Gaussian nature of the projected speckle pattern is used to reveal image disparity to sub-pixel accuracy. Processing is accomplished by compressing the images into sparse array format before they are correlated. This system is ideally suited for hardware implementation and circumvents many of the inherent limitations of multi- camera system using FFT spectral based correlation.

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