| Ghost imaging(GI)is a new type of computational imaging technique.It is different from the traditional optical imaging scheme in daily life,GI uses the second-order correlation function to correlate the light intensity information collected by the detector,so as to reconstruct the spatial information of the target to be measured.It has many advantages over conventional imaging,for example,it can achieve lensless imaging,occlusion imaging,and even reconstruct the image of the target object in atmospheric turbulence and scattering media.Therefore,it has received a lot of attention in the field of optics.With the development of ghost imaging technology,improving its resolution is an important research content.This thesis introduces a new amount of information from the statistical point of view-second-order cumulators instead of the traditional intensity fluctuation association information,discusses the change of the second-order correlation function after the introduction of new information quantities,and finds that after the introduction of second-order cumulators,the ghost imaging system contains more imaging information,thereby improving the resolution of the traditional ghost imaging system,which we call second-order cumulative ghost imaging(SCGI).Next,this article further discusses the effect on second-order cumulative information when the statistical characteristic of the light field of the light source is a non-Rayleigh distribution.It is found that the second-order cumulant information can be further optimized by using sub-Rayleigh speckle field as the light source.It is proved that the imaging resolution can be further improved by using the sub-Rayleigh speckle field as the light source based on the second-order cumulant ghost imaging model.Finally,through simulation and experimental verification,it is found that on the basis of SCGI,sub-Rayleigh speckle as illuminating speckle can get better resolution than the traditional Rayleigh speckle. |
