| Ghost imaging also known as quantum imaging,which is an imaging technology that obtains the image of the target object through the correlation operation of light field intensity fluctuation.Since 1990 s,ghost imaging has become a frontier hotspot with a series of properties such as anti-interference and super-resolution,and has been applied in many fields such as remote sensing,radar,super-resolution imaging,biomedicine and so on.How to achieve highquality imaging in complex surroundings is a problem and challenge faced by traditional imaging,so it is particularly important to carry out research on high-quality ghost imaging in complex surroundings.I carry out related research work on high-quality ghost imaging in complex environment.The paper is mainly divided into the following parts:The first part is the introduction,including the first two chapters.The first chapter introduces the research background and significance of this paper,reviews the development of ghost imaging and the research status at home and abroad,and expounds the main research contents of this paper.The second chapter expounds the coherence,the basic concepts and the theoretical derivations process of ghost imaging.The second part is the research of underwater ghost imaging,including the third chapter.In this chapter,the advantages of the diffraction-free characteristics of shaped Lorentz source in long-distance underwater imaging are discussed firstly,and the high-quality ghost imaging in the complicated underwater surrounding based on shaped Lorentz source is realized.When there is no turbulence or weak turbulence,the imaging quality of the long-distance underwater ghost imaging system can be significantly enhanced by adjusting the modulation factor of the shaped Lorentz source.Even there is relatively strong turbulence,by properly decreasing the modulation factor,the imaging quality still can be improved to some degree.Therefore,based on ghost imaging technology and shaped Lorentz source,high-definition imaging of underwater target objects under strong turbulence is realized,and our work may expand applications of ghost imaging in long-distance underwater imaging and submarine communication.The third part is the research of ghost imaging of axially fast-moving target,including the fourth chapter.In this chapter,the problem of high-quality imaging of objects with complex axial motion modes is discussed in strong scattering condition.Starting from the shaped light source,the cosine shaped sources is utilized to illuminate axially fast-moving object,and algorithm is designed to restore image of fast-moving object.We can properly choose the mode number and the maximal period of the cosine shaped source to effectively improve the resolution of the reconstructed images.By using this kind of cosine shaped source,our proposal works well for the axially fast-moving target with different motion models,such as uniform motion,acceleration motion and random motion,which opens a new door to imaging for the complexly moving target.Even there exists strong scattering media,high-quality images of the static or dynamic object are still reconstructed in our scheme.Therefore,this work solves the imaging problem of different motion models of axially fast-moving targets,and our works may be helpful for the real application of the ghost imaging system in forward-looking lidar detection.The fourth part is the research of asynchronous computing ghost imaging,including the fifth chapter.In this chapter,the study of asynchronous ghost imaging in strong scattering surrounding is carried out.Different from the previous synchronous detection mode of ghost imaging,this paper designs an asynchronous detection mode,in which the refresh rate of the light source is faster than that of the slow integration detector.In this paper,the imaging algorithm is theoretically derived and the feasibility of asynchronous detection and calculation ghost imaging is verified by experiments.In the aspect of high-quality imaging,this paper reconstructs the high-quality ghost imaging of two objects in the system with compressive sensing algorithm,and its measurement times are much less than that of synchronous detection.In the strong scattering surrounding,even in the presence of strong scattering medium interference,the image of the object is reconstructed by asynchronous detection.Therefore,this work enriches the application of ghost imaging system in detection,which provides great potential for the development and realization of ghost imaging in practical application,especially in X-ray imaging or ultra-low light scenes.The last chapter is the summary,which extracts the key points of the full text and looks forward to the follow-up work. |
