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PhlatCam: Designed Phase-Mask Based Thin Lensless Camera.

ABSTRACT: We demonstrate a versatile thin lensless camera with a designed phase-mask placed at sub-2 mm from an imaging CMOS sensor. Using wave optics and phase retrieval methods, we present a general-purpose framework to create phase-masks that achieve desired sharp point-spread-functions (PSFs) for desired camera thicknesses. From a single 2D encoded measurement, we show the reconstruction of high-resolution 2D images, computational refocusing, and 3D imaging. This ability is made possible by our proposed high-performance contour-based PSF. The heuristic contour-based PSF is designed using concepts in signal processing to achieve maximal information transfer to a bit-depth limited sensor. Due to the efficient coding, we can use fast linear methods for high-quality image reconstructions and switch to iterative nonlinear methods for higher fidelity reconstructions and 3D imaging.

SUBMITTER: Boominathan V

PROVIDER: S-EPMC7439257 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature

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PhlatCam: Designed Phase-Mask Based Thin Lensless Camera.

Boominathan Vivek V Adams Jesse K JK Robinson Jacob T JT Veeraraghavan Ashok A

IEEE transactions on pattern analysis and machine intelligence 20200423 7

We demonstrate a versatile thin lensless camera with a designed phase-mask placed at sub-2 mm from an imaging CMOS sensor. Using wave optics and phase retrieval methods, we present a general-purpose framework to create phase-masks that achieve desired sharp point-spread-functions (PSFs) for desired camera thicknesses. From a single 2D encoded measurement, we show the reconstruction of high-resolution 2D images, computational refocusing, and 3D imaging. This ability is made possible by our propos ...[more]

PMID: 32324539

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