Recently we have shown that light-field photography images can be interpreted as limited-angle cone-beam tomography acquisitions. Here, we use this property to develop a direct-space tomographic refocusing formulation that allows one to refocus both unfocused and focused light-field images. We express the reconstruction as a convex optimization problem, thus enabling the use of various regularization terms to help suppress artifacts, and a wide class of existing advanced tomographic algorithms. This formulation also supports super-resolved reconstructions and the correction of the optical system’s limited frequency response (point spread function). We validate this method with numerical and real-world examples.

Imagine Optic, Bordeaux, France
Optics Express
Volumetric medical x-ray imaging at extremely low dose
Centrum Wiskunde & Informatica, Amsterdam (CWI), The Netherlands

Viganò, N., Martínez Gil, P., Herzog, C., de la Rochefoucauld, O., Liere, R.V. (Robert Van), & Batenburg, J. (2019). Advanced light-field refocusing through tomographic modeling of the photographed scene. Optics Express, 27(6), 7834–7856. doi:10.1364/OE.27.007834