Research On Optical Coherence Tomography System By Time Domain And Spectral Domain

Optical Coherence Tomography (OCT), a novel imaging technique, was proposed in 1990s.It has many advantages such as high detecting sensitivity, non-invasiveness, high axial resolution for the imaging of living biological tissue and the high resolution and tomography imaging ability. At present, the research of OCT is going on higher spatial resolution, higher signal to noise ratio, higher sensitivity, faster speed of scanning and data acquisition, and deeper the detection depth etc.The development, application and background of OCT are introduced firstly. Based on analyzing the configuration and working principles of OCT, the time-domain imaging system and spectral domain OCT imaging system are constructed.Time-domain OCT with ASE source has coherence length up to 14μm. Build stepper motor platform is used to three dimensional scanning, design photoelectric detector module carry out interference signal. Base on Visual C++ programmed for serial interface motion control of stepper motor, PCI9112 data acquisition card to achieve the right detection circuit collection. Because of the ASE light source produced by side lobe effects, this paper presents a algorithm based on signal amplitude transformation. The results show that this algorithm can reduce the influence of sidelobe signal, remain most of the mainlobe signal. Finally, a three-dimensional image reconstruction and image processing is achievedSpectral-domain OCT with SLD source, designed and constructed optical vibration mirror scanning model system and spectrum signal processing system. Based on LabVIEW tools programming to realize DAQ2010 analog signal output which control Optical galvanometer and the scan through USB on the center line array CCD grating spectrometer receives the spectral signal acquisition display.