High-resolution digital holography using dual-wavelength coupled phase retrieval

In-line digital holography enables full image sensor bandwidth reconstruction, but its quantitative imaging capability is hampered by twin image artifacts resulting from spectral aliasing. Here, an in-line digital holography method based on dual-wavelength coupled phase retrieval (DwCPR) is proposed for non-crosstalk and high-resolution imaging. In this method, a single image sensor is used to capture an off-axis hologram and a composite in-line hologram at the same position through two exposures. The phase reconstructed from the offaxis hologram serves as the initial estimate, and an iterative model is established by coupling the dualwavelength composite in-line hologram. The high-resolution reconstruction is achieved through the application of dual-wavelength plane amplitude constraints and energy conservation principles. The proposed method can avoid pixel errors caused by multiple sensors and minimize the required measurements across multiple planes. More importantly, the combination of energy conservation and multiple amplitude constraints significantly enhances the reconstruction quality.