The Research Of 3D Intensity Correlation Imaging Based On Different Scattering Media

The correlation imaging technology can recover the object information by using a association operation between the reflected energy value and the spatiotemporal fluctuation of the speckle light.Traditional imaging always directly records the intensity of the reflected lights of the target object,which can be affected by phase distortion,loss,and transmission medium,and the quality of imaging is highly influenced by the environment.In recent years,the correlative imaging theories have been improved and many studies shown that correlative imaging has high detection sensitivity,strong antiscattering interference,and can use for non-local imaging.Therefore,correlation imaging technology has a broad application in the fields of multispectral imaging,infrared imaging,terahertz imaging,biological imaging,remote sensing detection and so on.The three-dimensional imaging can obtain the acquisition of three-dimensional information of objects based on the two-dimensional imaging.The information of the light field intensity/phase can be obtained,as well as the valule of distance.Such imaging technology is potential to be used in machine vision and facial recognition fields.In this work,it is devoted to the research of 3D correlation imaging.It combines correlation imaging technology to carry out high-quality and strong anti-noise,and uses Time of Flight(Time of flight,TOF)to obtain 3D information of the target scene.In a scattering environment,the scattering medium can scatter and absorb the photons,then the imaging quality will be affected greatly.However,correlation imaging technology has strong anti-scattering interference ability,which can reduce the influence of such scattering,even keep a complete anti-interference state.Based on the research of correlation imaging in a scattering environment,this paper proposed a three-dimensional intensity correlation imaging scheme with different scattering media.The main contents are as follows:1.This paper uses TOF technology and DGI reconstruction algorithm to carry out theoretical analysis,and numerical simulation and experimental verification.The simulation and experimental results show that the reconstructed slice image of two objects can be clearly seen.And according to the pseudo-color superposition calculation,the longitudinal distance is agreed well with the actual distance.For a certain range,with the increase of the parameter of threshold,the reconstruction quality is enhanced.The experimental results show that when increasing the power of the laser source,the time jitter of the echo signal can be effectively suppressed,and the reconstruction quality of the image and the longitudinal distance accuracy were improved well.2.A pseudothermo-light 3D intensity correlation imaging experimental system was designed and the transmitting and receiving parts of such system were introduced.It has a debugs hardware devices such as lasers,industrial computers,frosted glass controllers.It also contains a software debugging such as laser control,surveillance camera and reference arm settings,acquisition settings,and so on.3.Based on the 3D correlation imaging system,an underwater 3D correlation imaging system was proposed.The medium of acrylic,clear water + acrylic,and turbid water + acrylic were investaged,and the correlation imaging in such scattering media were analysed..In the reconstructed slice image,two objects appeared alone,and the longitudinal distance between them was obtained by 3D superposition calculation.When in a scattering environment,the reconstruction quality of 3D correlation imaging was obviously weaker than that without scattering medium.And a worse scattering environment would lead to a poor reconstruction quality,the ratio of reflected energy occupied by the front-end object also increased accordingly.However,the experimental results can still accurately draw the distance information between two objects.It proves that correlation imaging technology has strong anti-scatter interference ability.