基于光子计数的合作目标“量子”成像

“Quantum” imaging of cooperative target based on photon-counting regime

在实验上研究了赝热光照明下,基于光子计数模式的合作目标"量子"成像,并给出理论模型和解释.研究表明,利用光子计数的单光子探测器代替以往光强度线性探测器作为桶探测器在"量子"成像中同样适用.实验发现,合作目标的反射信号可穿透弱散射介质实现成像,该技术在减小光学成像透镜孔径方面具有潜在的应用价值.对比了基于强度关联成像和压缩感知算法的"量子"成像结果,并得出实用性结论.本文的方案为"量子"成像的实际应用提供了新方法.

＂Quantum＂ imaging is such an technique that the total light intensity transmitted through or reflected by an object is collected by a ＂bucket＂ detector, which generally is a photodiode with a collection lens in front and with no spatial resolution, and an image of the object can be retrieved through the assistance of another spatially correlated reference beam which does not interact with the object. In this paper, ＂quantum＂ imaging scheme is investigated, instead of using the conventional linear detector, and a single photon detector working in a photon-counting mode is used as a ＂bucket＂ detector, which is the most sensitive detector in the present. It is experimentally demonstrated that ＂quantum＂ imaging illuminating by pseudo-thermal light can be retrieved through using the single-photon detector working in the photon-counting mode, and the averaged power received by the ＂bucket＂ detector is only 2 femto-Watt. It is also experimentally and theoretically demonstrated that the image of the cooperative target can be recovered through the wake scattering medium, which cannot be realized by the classical imaging method. Furthermore, it is found that the wake scattering medium has the potential application in reducing the size of the collection lens of the bucket detector, in other words, enlarging the field of view. Besides, ＂quantum＂ imaging recovered by correlation of intensity fluctuations and compressive sensing algorithm are compared, and the most effective ways to retrieve the image are discussed. The scheme of our experiment which is different from the traditional ways, offers a novel method to make the ＂quantum＂ imaging technique step further toward its applications in wake light imaging or remote sensing.