Multi-wavelength varifocal common-path digital holographic microscopy

Abstract This study presents a common-path (CP) digital holographic microscopy (DHM) that employs computer-generated holograms specifically designed for individual imaging conditions. By integrating multi-wavelength operation and varifocal capability, the system can stably record and reconstruct object wavefronts across different wavelengths and varifocal conditions within a CP configuration. The experimental results demonstrate the feasibility and effectiveness of the proposed method, highlighting its robust phase reconstruction performance under various imaging conditions. The system’s practicality is further validated through quantitative phase imaging of white blood cells and microbeads under different wavelength and varifocal settings. The integration of these features significantly enhances the flexibility, stability, and adaptability of CP DHM, paving the way for broader application in high-precision imaging, quantitative phase analysis, and biomedical diagnostics.