CT Image Hologram Generation And Photoelectric Photoelectric Reproduction Of Human Brain

CT(Computed Tomography)can obtain the information of the internal tissues and organs of the human body without damage,which is a clinical medicine and its important auxiliary diagnosis method.CT images can only provide two-dimensional information of tissues and organs.The diagnosis of the lesion area often depends on the imagination of the doctor.Therefore,the reconstruction of the CT images to realize the three-dimensional reproduction of tissues and organs will help improve the efficiency of doctors' diagnosis.The essence of traditional 3D visualization of CT images based on computer graphics is the projection of 3D objects on a computer screen,and holographic technology can record the amplitude and phase of objects at the same time,which is an ideal true 3D visualization method.In view of the sparse CT image(number of layers),the holographic threedimensional display has poor visual continuity.In this paper,computer graphics and holographic theory are combined to synthesize slices to improve the quality of CT hologram generation and photoelectric reproduction.The specific work is as follows:(1)The background and significance of holography and the current research status and future development trend of holographic 3D display technology at home and abroad are briefly introduced and analyzed.Firstly,the basic theory of computational holography and the production process of computational holograms are described.Then,the principle of tomography computational holography is introduced.Finally,the characteristics of the two methods of three-dimensional visualization of CT images are combined.Problems and propose corresponding solutions.(2)Human brain CT image preprocessing and slice synthesis.Firstly,the preprocessing is combined with the characteristics of the CT image,including double threshold segmentation,filtering,etc.,and then use the Canny operator to extract the brain tissue contour from the CT image,and then segmentation to obtain CT image information of the internal organs of the human brain;Then,based on the VTK(visualization toolkit)tool library,the rough three-dimensional model of the human brain is reconstructed from the CT image information of the internal organs of the human brain and discretized to obtain the point cloud,and the PCL(Point Cloud Library)tool library is used to perform the point cloud Poisson surface reconstruction to obtain a smooth surface model of the human brain;Finally,VTK is used to slice and synthesize the human brain model to obtain the CT image data of the human brain required for tomography calculation hologram production.(3)DMD photoelectric reconstraction.First introduce the structure and working principle of DMD,and then deeply analyze the reasons for the degradation of the hologram reproduction image and optimize the image quality,mainly in two ways: One is to use the bipolar intensity calculation method for gradation modulation technology to process the hologram to make the hologram close to binarization,so as to better meet the DMD display characteristics;The second is to select a suitable filtering method to eliminate the zero-order light interference in the hologram reproduction image.The experiment of constructing the optical path to reproduce the hologram shows that the image quality of the human brain CT image hologram reconstruction after image quality optimization has achieved a certain degree of visual improvement.