Integrated Imaging System Of Axial Length And Anterior Segment Based On SS-OCT

SS-OCT uses a broadband tunable sweep source to reconstruct image depth information by inverse Fourier transform of spectral signals,has the characteristics of micron-scale high resolution,high-signal-to-noise ratio,instantaneous imaging and non-contact imaging.It has been widely used in clinical diagnosis of ophthalmology,and has realized rapid and non-invasive imaging of living eyes.In this paper,the imaging principle of SS-OCT and its application in ophthalmology clinical diagnosis and treatment are analyzed.On this basis,an integrated imaging system of axial length and anterior segment based on SS-OCT are proposed.It can complete the measurement of the axial length and the two-dimensional imaging of the anterior segment.Through image enhancement and location algorithm,the measurement accuracy of eye parameters is improved.The researches and main work of this paper are as follows:1.An integrated imaging system of axial length and anterior segment based on SSOCT is designed.There are two imaging modes,one is the axial length measurement system(1D)and another is the integrated imaging of axial length and anterior segment.Then a calibrated optical path is built for K-domain resampling to improve the imaging quality in large range interference.And the results are presented by real-time display system.2.A Dispersion Compensation Method based on depth adaptation is proposed.A linear relationship is existed between the dispersion compensation coefficients at different depth.Therefore,the algorithm seek the optimal solution of several positions by the Golden Section so that the dispersion compensation coefficients of all range can be calculated.The resolution of the system image is obviously improved by the proposed algorithm.3.The algorithm combines the Fourier transform and non-local means algorithm to suppress the speckle noise.The Mahalanobis distance is used to optimize the similarity calculation method in the non-local means.And the improved non-local means algorithm is applied to the high-frequency components in order to avoid the information loss of low-frequency components.A bilinear difference regression algorithm is also proposed.It utilizes the Bilinear Fitting of paraxial pixels for the accurate positioning of each layers in the OCT image,which has an excellent testing results.4.The integrated imaging system of axial length and anterior segment based on SS-OCT was built,and the imaging experiments of eye model and biological tissue samples were carried out.The experimental results show that the system designed and constructed in this paper can realize the one-dimensional measurement of axial length and the two-dimensional transverse scanning of the axis and the anterior segment.The algorithm proposed in this paper can effectively improve the imaging quality of the system.