Fast Oct Integrated Control System Design And Development

Optical coherence tomography (OCT) is a novel optic tomography technique which has many advantages, such as non-contact and non-invasion detection, high resolution, high sensitivity for the imaging of living biological tissue. It has been possessed of great development potential application in medicine and biology. Conventional time-domain OCT with single-point detection technique acquires the interference signal point and point. It is a time-consuming process to create a cross-sectional image, so this kind of scanning mode may be one of the main constraint factors for high-speed imaging. When Fourier-domain technique is performed in OCT system, depth-scan information is provided by an inversion Fourier transformation of the spectrum of the back scattering light. The time-consuming mechanical OCT depth-scan can be put aside and the video rate imaging could be possible.Besides, complex spectral Fourier-domain OCT technology can suppress the alias phenomena effectively when we rebuild the image of complex tomographic structure of specimen. Therefore, complex spectral Fourier-domain OCT technology puts Fourier-domain technique into a new development stage.This thesis analyses the OCT system principle and its working process. Then it puts forward a design thought. The design thought is to unify various modules to the rapid OCT integrated control system. These modules include scanning control signal, galvanometer driving signal and synchronization control signal. The system regards C8051F020 MCU as the core. According to the design thought, we design a rapid OCT integrated control system including hardware and software and construct a specific rapid OCT integrated control system. The system can be used in time domain OCT system as well as in frequency domain OCT system. Experimental results show that the rapid OCT integrated control system can meet the design requirement in the scanning speed, scanning range and scanning resolution.This paper is divided into five chapters of the text. Chapter 1 introduces development process of OCT technology briefly, analyses characteristics and performance of time domain OCT technology and frequency domain OCT technologhy. It also introduces embedded microcontroller,embedded application and research contents and research taigets of this thesis; Chapter 2 introduces the principle of frequency domain OCT, analyzes frequency domain OCT system constructed by our laboratory in detail, analyzes signals and control logic of time domain and frequency domain OCT system and discusses the work to be accomplished in the embedded design; Chapter 3 introduces the hardware design of the rapid OCT integrated control system and analyses circuit design principle of each hardware module in detail. Besides, the chapter also introduces the printed circuit board design of the whole hardware circuit; Chapter 4 introduces the software design of the rapid OCT integrated control system, discusses flowchart of software module in detail and lists some software programs; Chapter 5 tests the whole system designed by my laboratory, displays some experimental results, put forward the existing problems and points out further improvement that can be made.