Research On Performance Improvement Of Reconstruction Algorithm And Development Of Experimental System For Ghost Imaging

Correlated imaging,also known as ghost imaging,is a novel imaging technique that can be imaged in harsh and extreme environments and has wide application prospects in military,remote sensing,medicine and so on.Different from the traditional imaging methods which collect the resolution information of the target object,the ghost imaging only collects the total light intensity after the probe light passes through the object.The imaging result of the target object is calculated by using the high-order correlation information of the light source and the total light intensity after the object,so the method has the advantages of strong anti-interference ability,super-resolution and simple detector.However,the ghost imaging technique is difficult to calculate satisfactory imaging results in a limited time and therefore not easy to be practical.Ghost imaging system can be divided into two parts: data processing algorithm and optical system,so the work in this paper is mainly divided into two aspects.In the algorithm aspect,a new reconstruction algorithm,ghost imaging using the binomial theorem,is proposed.And in the optical system aspect,a ghost imaging experimental system is developed.The performance of the ghost imaging reconstruction algorithm is the key to determine whether it can be applied in the future.Aiming at the performance issues of the reconstruction algorithm,in this paper,a deep study is made on the existing algorithms,and the two ways to improve the reconstruction quality are summarized by matrix theory.Based on this,the two ideas are applied synthetically,and the new reconstruction algorithm is proposed to improve the reconstruction performance in balance,which is of practical significance.The optical system provides the real data source for the subsequent reconstruction algorithm,and the reconstruction algorithm must also be tested by the real data in the end.In this paper,the ghost imaging experimental system and the controller of the system is developed,and the imaging data is finally collected.The reconstruction quality,reconstruction time and robustness of the reconstruction algorithm are the constraints that hinder the practicality of ghost imaging.Nonlinear reconstruction algorithms use modern numerical solution theories,such as compressed sensing theory and pseudo-inverse theory.Although the reconstruction quality is greatly improved,it is very sensitive to external noise and consumes a lot of calculation time.However,the traditional linear algorithm uses the correlation average operation.Although the reconstruction quality is not high,the reconstruction time is less and the robustness is stronger.By establishing the matrix model of the reconstructed system,the noise introduction mechanism of the reconstructed system is analyzed,and two ideas of the reconstructed algorithm to remove the noise are finally summarized.In this paper,the imaging reconstruction algorithm using the binomial theorem is proposed to improve the reconstruction performance.This scheme is a follow-up processing of other reconstruction algorithms.Constructing binomial summation of reconstruction results can reduce the noise term of characteristic matrix indirectly.So it can be combined with linear algorithm to further improve the reconstruction quality while avoiding complex calculation and maintaining robustness.The experimental results show that the algorithm combined with differential ghost imaging can improve the reconstruction effect of gray image to a level comparable to that of compressed sensing ghost imaging algorithm,and has more advantages in computing time and robustness.Finally,the experimental system is developed according to the experimental architecture of ghost imaging.The core of the experimental system is the preparation of pseudo-thermal light source.Based on the STM32 micro-controller,the system realizes the preparation of pseudo-thermal light source and the synchronous acquisition of data.The experimental system can control the rotating ground glass to generate the corresponding motion trajectory according to the experimentalparameters input by the touch screen,and trigger the camera acquisition synchronously.