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arXiv · 1608.03211

Subdiffraction incoherent optical imaging via spatial-mode demultiplexing

Mankei Tsang
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Abstract

I propose a spatial-mode demultiplexing (SPADE) measurement scheme for the far-field imaging of spatially incoherent optical sources. For any object too small to be resolved by direct imaging under the diffraction limit, I show that SPADE can estimate its second or higher moments much more precisely than direct imaging can fundamentally do in the presence of photon shot noise. I also prove that SPADE can approach the optimal precision allowed by quantum mechanics in estimating the location and scale parameters of a subdiffraction object. Realizable with far-field linear optics and photon counting, SPADE is expected to find applications in both fluorescence microscopy and astronomy.

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Mankei Tsang. 2016-08-09. Subdiffraction incoherent optical imaging via spatial-mode demultiplexing. https://doi.org/10.1088/1367-2630/aa60ee

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