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Conference on Lasers and Electro-Optics

Quantum-Optimal Discrimination of Multiple Objects in Sub-Diffraction Incoherent Imaging

Michael R. Grace, Saikat Guha

Published Jan 1, 2022• 0 citations
Publisher

Abstract

We derive the quantum limit for discriminating between M≥2 incoherent, diffraction-limited objects and identify a quantum-optimal measurement that can distinguish two orders of magnitude more objects than direct imaging with no additional error.
DOI
10.1364/cleo_at.2022.jth3a.29

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We consider passive imaging tasks involving discrimination between known candidate objects and investigate the best possible accuracy with which the correct object can be identified. We analytically compute quantum-limited error bounds for hypothesis tests on any library of incoherent, quasimonochromatic objects when the imaging system is dominated by optical diffraction. We further show that object-independent linear-optical spatial processing of the collected light exactly achieves these ultimate error rates, exhibiting scaling superior to spatially resolved direct imaging as the scene becomes more severely diffraction limited. We apply our results to example imaging scenarios and find conditions under which superresolution object discrimination can be physically realized.
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