High dynamic range structured illumination microscopy based on multi-channel fusion and dual-phase binary fringe

Binary fringe projection holds significant promise for three-dimensional structured illumination microscopy (SIM) due to its high efficiency and precision. However, its performance is limited by fringe edge blurring and localized over- or underexposure on highly reflective surfaces, leading to demodulation failure and incomplete measurement. This paper proposes a high dynamic range SIM based on multi-channel fusion and dual-phase binary fringe (MFDBF-SIM). By introducing a phase shift between axially adjacent binary fringes, the zero-modulation regions resulting from edge blur are distributed alternately between odd and even layers, thereby avoiding local information loss. Furthermore, differential intensity responses across RGB channels are utilized to adaptively select the optimal modulation curve, enabling high dynamic range reconstruction. A horizontal correction model and a scanning-step-based calibration model are developed to compensate for horizontal error caused by Bayer interpolation and axial focal-plane offset induced by lens longitudinal chromatic aberration, respectively. Experimental results on silicon wafer and printed circuit board samples demonstrate that MFDBF-SIM improves reconstruction integrity by 121.5% and 224.6% compared to the single-channel methods using only the green or blue channel.