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High-speed spectral-domain optical coherence tomography at 830nm wavelength

We present a high-speed spectral domain optical coherence tomography (SD-OCT) system at 830 nm wavelength which is consisted of a fiber based Michelson interferometer and a custom-built spectrometer. The designed resolution of the spectrometer is about 67.4pm which limits the maximum detection depth 2.56mm in air. And the 35us exposure time of the high speed line scan CCD makes real-time imaging possible. Furthermore, a novel method of spectrometer calibration is put forward. The method can remove the influence of dispersion mismatch, thus accurately determine the distribution of wavelength on the line scan CCD, which leads to a precise interpolation and a subsequent better contrast image.