A high-speed, ultra-broad band wavelength swept source based on Fourier domain mode-locking (FDML) technique was demonstrated. Two semiconductor optical amplifiers were used as the gain media. The laser is capable of FWHM tuning range of more than 180 nm and the edge-to-edge scanning range of more than 220 nm at 100 kHz sweeping rate. With the built swept source, an ultra high resolution high speed FDOCT system was developed which can achieve axial resolution of 3 μm in tissue. Imaging of rabbit trachea was demonstrated with the FDOCT system.© (2010) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.