Dual-source swept-source optical coherence tomography (DS-SSOCT) has two individual sources with different central wavelengths, linewidth, and bandwidths. Because of the difference between the two sources, the individually reconstructed tomograms from each source have different aspect ratio, which makes the comparison and integration difficult. We report a method to merge two sets of DS-SSOCT raw data in a common spectrum, on which both data have the same spectrum density and a correct separation. The reconstructed tomographic image can seamlessly integrate the two bands of OCT data together. The final image has higher axial resolution and richer spectroscopic information than any of the individually reconstructed tomography image. Optical coherence tomography (OCT) is a powerful imaging technology for producing high-resolution cross-sectional images of the internal microstructure of materials and/or biological samples. It has been widely used in medical imaging and biological testing for more than ten years [1–4]. Swept-source optical coherence tomography (SS-OCT) [5, 6] has significant signal-to-noise ratio and speed advantages over time-domain OCT [7–9], in which, the broadband laser swept source plays an important role. The linewidth and output power of the source determinate the imaging depth and sensitivity of an SS-OCT system. The bandwidth of the light source determine the imaging axial resolution. At current stage, most commercial available swept sources have a bandwidth about 100？nm corresponding to an axial resolution around 7.4？μm in air. In some medical applications, when spectral feature appears at a wavelength differing from the central wavelength of the light source or the photo sensor, it could not be investigated by the single-band OCT system. In order to extract more spectral information and enhance the axial resolution, simultaneously imaging at two distinct spectral regions has been demonstrated by time-domain [10], full-field [11], and spectral-domain [12, 13] OCT systems. Actually, in all the reported dual-band OCT systems, the two sets of band data are produced from the same light source. In time-domain OCT, as the depth information is obtained by means of depth scanning, both the reconstructed images of different bands have the same image dimensions. An effective and practical method for resolution enhancement in dual-beam time-domain OCT had been reported by Baumgartner et al. [14]. For the spectral-domain OCT, as two bands data produced by the same source, the imaging ranges also have the same depth range, if the spectrum data
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