| The blood vessels only in Human eye retinal can be observed directly. Many diseases that are not obvious in their early symptom can be diagnosed through observing the changes of distal micro blood vessel. But because of the human eye aberration, high resolution imagings of retina cell and micro blood vessel with the diameter of 10μm are impossible obtained through the eye fundus camera currently used in clinic applications. Only simple diseases, such as visual disc edema, can be checked through it.In 1994, Liang and Williams introduce the adaptive optics technique for astronomical observation and laser shaping into the human eye retina imaging. And in 1997, they obtained the high resolution image of human eye retina through their adaptive optics system for the first time.The deformable mirror is usually used as the wavefront corrector in a traditional adaptive optics because of its fast response speed. Therefore, it is able to correct the fast changing aberrations caused by atmospheric turbulence in astronomical observation fields. However, in the application of retinal imaging observation, the aberration of eye is very large, and the DM actuator number is small, which Leads to poor correction results fsufferers with complex aberrations, especially the middle-aged and senile suffers; In addition, the price of DM is high. Therefore, the investigation advancement based on DM is slow. The reports about the micro blood vessels that are not sensitive to the light are very few.In the thesis, the liquid crystal wavefront corrector based on LCOS has been used. It has many merits, such as, low cost, large number of actuators, low driving voltage and programmable controlling. A liquid crystal (LC) adaptive optics system (AOS) was built based on liquid crystal on silicon (LCOS) to correct the aberration of human retina. Because the start time of investigation of LC AOS is relatively late and its light loss is large, the successful cases of observation of micro blood vessel in retinal have not been reported.In the paper, design and optimization of the system controlling software for the available LC AOS were conducted. In addition, through the imaging processing ways, it can processing the retinal images in real time. The image noise was decreased through both software and hardware ways, which improve the image quality very well; A two-step exposure and recover algorithm was presented to process the human retina micro blood vessel's blurred images and obtain clear ones in real time. To resolve the dithering problem of human retina micro blood vessels, a center area best condition matching algorithm was presented, which successfully stabilized the images of retina micro blood vessels during dynamical observation and resolve the non real-time processing problem for the post-image processing method used by many researchers; To obtain a large FOV image of the retinal micro blood vessel, one has to grab tens of small FOV images and stitching them together. To keep the CCD locating on the position of focus plane, a design of adaptive tracking equipment for imaging CCD was presented. Our simulation results indicate that it resolves the blurred image problem caused by movement of eyeball; For the image stitching method, I improved the traditional Harris corner point checking method to make it more appropriate for the image stitching of retinal micro blood vessel. In the emulation, it realized the image stitching fastly and accurately, which improved the work efficiency greatly,This paper presents the novelty work about the controlling of LC AOS for human retina and image processing, which resolved a series of problems that occurred in applications and indicated the originality of image processing technique...
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