Research Of Prism Based Endoscopy 3D Display Technology

Compared with conventional endoscopy, medical stereo endoscopy can achieve 3D display and provide image depth information.Thus, stereo endoscopy is more advantageous to locate the lesions position and accuratly diagnose diseases in order to help doctors reduce the rate of misdiagnosis. So stereo endoscopy is widely used in the process of diagnosis and surgical treatment. However, now medical stereo endoscope mostly utilizes two cameras or multi-cameras to capture images. And the method not only increases the diameter size of the endoscope, but restricts the application fields of stereo endoscopy.On one hand,the method utlize two cameras or multi-cameras to collect images,to increase the production cost of medical stereo endoscope;on the other hand, the method can not diagnose smaller lesions,because using two cameras or multi-cameras makes the size of stereo endoscopy large.In view of the above problems, this paper put forward and realized the research of prism based single camera 3D display techno logy. The system uses a prism and single camera to realize 3D display, without increasing the diameter of the endoscope. According to the theory of "virtual camera" and the method of image sensor plane midpoint projection, single camera based on prism medical endoscope 3D display can be realized by using NVIDIA corporation active shutter 3D display technology. The main finished works in this dissertation include:Firstly, according to the formula for the depth of field of the camera, the location ranges of the object can be determined., then according to camera calibration method the internal and external parameters of the camera can be determined; according to the camera parameters, the transformation relations between the world coordinate system and the camera coordinate system transformation relations can be used to solve the angle between two cameras and the distance between the two cameras.Secondly, according to the method of image sensor plane midpoint projection, the geometrical optics model of the position relationship between the single camera based on prism and two cameras can be builed.Then, the parameters of the prism angles and positions can be so loved by using Newton Iterative Algorithm.Thirdly, according to the above theory, the system of prism based single camera 3D display can be designed and implemented.The whole system consists of hardware part and software part, respectively, to complete the task of image acquisition and image processing.Compared with the existing 3D display system, this system use single camera and a prism to realize 3D display.If the principle is widely used to the stereo endoscope field, the production cost of stereo endoscope can be greatly reduced.The experimental results show that the 3D display effect of the system is conform to the human eye visual effect.In this paper, with the aid of the NVIDIA corporation active shutter 3D display technology, a novel kind of stereo imaging method is proposed, which realizes 3D display by single camera and a prism, and the method changes the inconvenience of two cameras and multi-cameras to realize the 3D display, and makes 3D display system more exquisite and convenient. If the principle is widely used to the stereo endoscope field, stereo endoscope can be more exquisite and convenient.