Historically, the resolution of optical imaging systems was dictated by diffraction, and the Rayleigh criterion was long considered an unsurpassable limit. In superresolution microscopy, this limit is overcome by manipulating the emission properties of the object. However, in passive imaging, when sources are uncontrolled, reaching sub-Rayleigh resolution remains a challenge. Here, we implement a quantum-metrology-inspired approach for estimating the separation between two incoherent sources, achieving a sensitivity five orders of magnitude beyond the Rayleigh limit. Using a spatial mode demultiplexer, we examine scenes with bright and faint sources, through intensity measurements in the Hermite–Gauss basis. Analyzing sensitivity and accuracy over an extensive range of separations, we demonstrate the remarkable effectiveness of demultiplexing for sub-Rayleigh separation estimation. These results effectively render the Rayleigh limit obsolete for passive imaging.

中文翻译：

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光源的超灵敏分离估计

从历史上看，光学成像系统的分辨率是由衍射决定的，瑞利准则长期以来被认为是不可逾越的极限。在超分辨率显微镜中，通过操纵物体的发射特性可以克服这一限制。然而，在被动成像中，当光源不受控制时，达到亚瑞利分辨率仍然是一个挑战。在这里，我们采用了一种受量子计量学启发的方法来估计两个不相干源之间的间隔，实现了超出瑞利极限五个数量级的灵敏度。使用空间模式解复用器，我们通过埃尔米特-高斯基础上的强度测量来检查具有明亮和微弱光源的场景。通过分析广泛的分离范围内的灵敏度和准确性，我们证明了多路分解对于亚瑞利分离估计的显着有效性。这些结果有效地使得瑞利极限对于被动成像来说已经过时。