Quantum light-field microscopy for volumetric imaging with extreme depth of field

Light-field microscopy (LFM) is a three-dimensional microscopy technique whereby volumetric information of a sample is gained by simultaneously capturing both the position and momentum information of light illuminating the sample. Conventional LFM designs generally require a trade-off between position and momentum resolution, requiring one to sacrifice resolving power for increased depth of field (DOF). In this work, we demonstrate a LFM design that does not require this trade-off by utilizing the inherent correlations between spatial-temporal entangled photon pairs. Here, one photon from the pair is used to illuminate a sample from which the position information of the photon is captured directly by a camera. By virtue of the momentum anticorrelation between the two photons, the momentum information of the illumination photon can be inferred by measuring the momentum of its entangled partner. By using a wave-optics approach for the light-field reconstruction, we demonstrate that a resolving power of up to $5\text{μ}m$ can be maintained with a DOF of approximately $500\text{μ}m$, approximately 10 times that of a conventional LFM or $>100$ times that of a bright-field microscope. In the extreme, at a resolving power of $100\text{μ}m$, it is possible to achieve near infinite DOF.