Hong–Ou–Mandel (HOM) interference—the bunching of indistinguishable photons at a beamsplitter—is a staple of quantum optics and lies at the heart of many quantum sensing approaches and recent optical quantum computers. Here we report a full-field, scan-free quantum imaging technique that exploits HOM interference to reconstruct the surface depth profile of transparent samples. We demonstrate the ability to retrieve images with micrometre-scale depth features with photon flux as small as seven photon pairs per frame. Using a single-photon avalanche diode camera, we measure both bunched and anti-bunched photon-pair distributions at the output of an HOM interferometer, which are combined to provide a lower-noise image of the sample. This approach demonstrates the possibility of HOM microscopy as a tool for the label-free imaging of transparent samples in the very low photon regime.

Hong-Ou-Mandel (HOM) 干涉——在分束器上聚集无法区分的光子——是量子光学的主要部分，是许多量子传感方法和最近的光学量子计算机的核心。在这里，我们报告了一种全场、无扫描的量子成像技术，该技术利用 HOM 干涉来重建透明样品的表面深度分布。我们展示了检索具有微米级深度特征的图像的能力，其中光子通量小至每帧七个光子对。使用单光子雪崩二极管相机，我们在 HOM 干涉仪的输出端测量聚束和反聚束光子对分布，将它们结合起来提供样品的低噪声图像。