Compact dual-wavelength common-path digital holographic microscope for dynamic topography reconstruction

In this study, we present a compact dual-wavelength common-path digital holographic microscopy (DHM) system for high-precision morphological and dynamic measurements. The system ensures high-precision measurements with simpler optical path layout and calibration mode. The time stability of the system is firstly evaluated and compared with traditional dual-wavelength DHM setups, demonstrating significant improvement in noise suppression and measurement precision. Then, topographic measurements of a standard step sample with a height of 4 μm are carried out, showing an overall standard deviation of surface height of 47.83 nm, which is notably lower than that obtained with conventional systems. Finally, the system's dynamic imaging capability is demonstrated through real-time tracking of the movement of platymonas, confirming the system's excellent performance in dynamic monitoring. The proposed DHM system offers high stability, accuracy, and real-time capability, making it suitable for a wide range of applications in biological dynamic imaging and material science.