Research On Line-field Swept Source Optical Coherence Tomography System

Recently,Optical Coherence Tomography(OCT)has been widely developed due to its performance of non-invasive,non-contact,high resolution and sensitivity imaging,et al.OCT technology can be divided into two categories which are Time /Fourier Domain OCT(TD/FD-OCT)according to the principle,FD-OCT can be divided into two kinds which are Spectral Domain OCT(SD-OCT)and Swept Source OCT(SS-OCT)according to the source selected and the way in which interference signal can be gotten,compared with TD-OCT,the imaging speed and sensitivity of SS-OCT are better due to no need of scanning system,thus,it has a broad application prospect.Optical designs of line-field swept source OCT systems are presented as methods to achieve high speed and quality 2D/3D imaging,The main work is completed as follows:The principle and classifications of medical imaging technology are summarized,some typical technologies are compared according to characteristics,OCT technology is researched on the classification and development of the system.Integration with multiple subjects and theoretical basis of OCT technology are discussed.The structure of OCT system and principle of SS-OCT are presented.The key parameters of Laser swept source and its impact on other parameters of system are discussed.The designing scheme and parameters of 2D line-field SS-OCT system are determined,Line-field mode with uniform energy distribution instead of point-field mode with Gaussian distribution is proposed to be considered in the sample arm to make the edge of fringes clearer,the static system is accomplished to achieve 2D image without scanning system to increase imaging speed,two arms are designed through Zemax sequential mode and combined with a beam splitter in non-sequential mode to achieve ray tracing and verify the ability of interference of the whole system,and the influence of the line by the adjustment of beam splitter and reference arm is analyzed.On the basis of 2D system,an aspherical cylindrical lens instead of two aspherical lens and two cylindrical lens with a scanning mirror and another mirror are utilized in sample arm to achieve the optical design of beam shaping scanner for SS-OCT system,2D/3D imaging can be achieved with the static system/with the help of scanning system in a direction,interference ability and line energy distribution during the scanning process can be verified in the same way as the former design,it is concluded that the designing system can be a feasible and valuable solution for high quality imaging.