Phase retrieval without prior knowledge via single-shot Fraunhofer diffraction pattern of complex object

TL;DR

This paper introduces a novel method for phase retrieval from a single-shot Fraunhofer diffraction pattern of complex objects, eliminating the need for prior knowledge or multiple measurements, thus broadening applications in coherent diffraction imaging.

Contribution

The authors propose a high-density sampling scheme enabling phase retrieval from a single diffraction pattern without prior knowledge or multiple measurements.

Findings

Simulation confirms feasibility of the method.

Experimental results validate the approach.

Reconstruction reveals depth and refraction index information.

Abstract

Fraunhofer diffraction is a well-known phenomenon achieved with most wavelength even without lens. A single-shot intensity measurement of diffraction is generally considered inadequate to reconstruct the original light field, because the lost phase part is indispensable for reverse transformation. Phase retrieval is usually conducted in two means: priori knowledge or multiple different measurements. However, priori knowledge works for certain type of object while multiple measurements are difficult for short wavelength. Here, by introducing non-orthogonal measurement via high density sampling scheme, we demonstrate that one single-shot Fraunhofer diffraction pattern of complex object is sufficient for phase retrieval. Both simulation and experimental results have demonstrated the feasibility of our scheme. Reconstruction of complex object reveals depth information or refraction index; and single-shot measurement can be achieved under most scenario. Their combination will broaden the application field of coherent diffraction imaging.