Yu Wenkai

Sub-Rayleigh limit imaging via intensity correlation measurements

We demonstrate sub-Rayleigh limit imaging of an object via intensity correlation measurements. The image completely unaffected by the disturbance of diffraction-limit is achieved under the condition that the imaging system has an appropriate field of view. The resolution of this sub-Rayleigh limit imaging system is only tied to the lateral resolution of the illumination light.

Ghost imaging based on Pearson correlation coefficients

Correspondence imaging is a new modality of ghost imaging, which can retrieve a positive/negative image by simple conditional averaging of the reference frames that correspond to relatively large/small values of the total intensity measured at the bucket detector. Here we propose and experimentally demonstrate a more rigorous and general approach in which a ghost image is retrieved by calculating a Pearson correlation coefficient between the bucket detector intensity and the brightness at a given pixel of the reference frames, and at the next pixel, and so on. Furthermore, we theoretically provide a statistical interpretation of these two imaging phenomena, and explain how the error depends on the sample size and what kind of distribution the error obeys. According to our analysis, the image signal-to-noise ratio can be greatly improved and the sampling number reduced by means of our new method.