Design Of Fiber Polarization-Sensitive Optical Coherence Tomography System For Medical Detection

Optical coherence tomography (OCT) is a newly developed medical imaging method. It has the advantages of non-contact, non-invasive and high resolution. With the help of coherent light, OCT is able to detect pathological changes of internal tissues, which makes it an excellent evidence for diagnosing. Nowadays, biopsy is still the most important way to diagnosing early cancer, which will cost the patients a long painful time. But OCT will make the real-time, non-invasive diagnosis of these diseases possible. And that is what makes it a medical imaging method with bright future.Polarization-sensitive OCT (PS-OCT) is a functional extension of standard OCT. It is sensitive to birefringence changes, and is suitable for diagnosing diseases that change birefringence, e.g. glaucoma, cancer and burn.This paper focused on the fiber PS-OCT. First, it introduced the character of PS-OCT and its development indoor and abroad. Then, it analyzed the imaging theory of PS-OCT. After discussing the difference between fiber and non-fiber PS-OCT, it displayed the difficulties of building a fiber PS-OCT. And with the research on the influence of fiber on light polarization state, the paper put forward some solutions. On this basis, a fiber PS-OCT was set up, and a primary experiment was done, whose result was taken as the target for processing module design. After all these were finished, the experiment was done with the current system, results were gotten and analyzed. At last, the program of FPGA which controls the synchronization was written and emulated, with a satisfying result gotten.