Depth-resolved dispersion compensation method for optical coherence tomography imaging based on rectangular window function optimization

In the optical coherence tomography system, the mismatch in dispersion between the two interference arms will reduce the axial resolution of the system. Therefore, dispersion compensation is required. However, the current depth-resolved dispersion compensation method uses a fixed window function to extract signals at different depths, which has phase calculation error and reduces the accuracy of dispersion compensation. In this paper, we optimized the rectangular window function for the signal interception. According to the functional relationship between the phase and the wave number in the presence of dispersion, the second-order fit to the obtained phase is performed and the standard error of the fit result is used as the criterion. The optimized rectangular window is used to intercept the signal and perform FFT, thereby effectively reducing the phase error caused by the window function. And we accurately extracted the dispersion coefficients of samples to improve the accuracy of dispersion compensation.