The Analysis Of Temporal Cross-correlation Ghost Imaging In Noise Suppression

Ghost imaging is a method to obtain images of objects by using light field fluctuations.It can achieve single-pixel imaging and has the characteristics of high sensitivity and anti-interference.In recent years,it has attracted people’s attention and obtained rapid development.Although it has a certain resistance to background light interference,bucket detection is inevitably affected when there are strong background light and detection noise.Then the signal-to-noise ratio decreases,thus affecting the quality of associated imaging.Time-domain cross-correlation ghost imaging uses the time and spatial freedom of light field to acquire images,which provides a new method for improving the anti-noise ability of correlation imaging.This paper focuses on the study of ghost imaging under the condition of low SNR,focuses on the anti-noise performance of time-domain cross-correlation ghost imaging and carries out theoretical analysis,numerical simulation and experimental verification.Firstly,based on the imaging mechanism of ghost imaging,it is clear that the effective detection of echo intensity fluctuation rather than intensity itself is the key to obtain clear images,and the signal-to-noise ratio of ghost imaging bucket detection is redefined accordingly.That is,the ratio of signal fluctuation to noise fluctuation is the bucket detection SNR.Furthermore,the influence of additive noise in bucket detection on image quality of ghsot imaging is analyzed,.And the influence of pulse amplitude and pulse quantity on image quality in time domain ghost imaging is discussed,which provides a basis for the design of ghost imaging experimental system under the condition of low SNR.Experimentally,1.3km time-domain cross-correlation ghost imaging is achieved in the noon period,which verifies that the time-domain cross-correlation method can effectively improve the quality of correlation imaging.Furthermore,the time-domain cross-correlation results are applied to the distance measurement of objects to achieve 3d correlation imaging.The factors affecting range resolution in time domain cross-correlation 3d imaging are discussed.For remote imaging applications,the single-photon correlation imaging is explored,and the images of objects with a distance of 1.3 km are obtained under the condition that the average number of detected photons is less than 0.1.The feasibility of time-domain correlation imaging under the condition of single-photon detection is verified.