Accurate depiction of waves in temporal and spatial is essential to the investigation of interactions between physical objects and waves. Digital holography (DH) can perform quantitative analysis of wave–matter interactions. Full detector-bandwidth reconstruction can be realized based on in-line DH. But the overlapping of twin images strongly prevents quantitative analysis. For off-axis DH, the object wave and the detector bandwidth need to satisfy certain conditions to perform reconstruction accurately. Here, we present a reliable approach involving a coupled configuration for combining two in-line holograms and one off-axis hologram, using a rapidly converging iterative procedure based on two-plane coupled phase retrieval (TwPCPR) method. It realizes a fast-convergence holographic calculation method. High-resolution and full-field reconstruction by exploiting the full bandwidth are demonstrated for complex-amplitude reconstruction. Off-axis optimization phase provides an effective initial guess to avoid stagnation and minimize the required measurements of multi-plane phase retrieval. The proposed strategy works well for more extended samples without any prior assumptions of the objects including support, non-negative, sparse constraints, etc. It helps to enhance and empower applications in wavefront sensing, computational microscopy and biological tissue analysis.

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Modern quantitative optical imaging is developing toward high throughput and powerful data processing capabilities. Holography is a powerful technique to characterize quantitative phase delays introduced by light–matter interactions. The spatial bandwidth utilization of imaging sensors in digital holography can be expanded via an off‐axis multiplexing technique, which is a powerful tool for high‐throughput quantitative optical imaging. However, the highest bandwidth utilization of sensor is limited at 58.9% to keep the signal spectra away from the zeroth spectra. Kramers–Kronig relation is introduced into the off‐axis multiplexing technology to allow for the overlapping between the signal spectra and unwanted spectra. The bandwidth utilization of sensor in a diffraction‐limited optical system can reach 78.5% in one hologram. It opens a new route to multiplexing quantitative optical imaging and helps to improve the performance of iterative‐free and constraint‐free modern optical microscopes in various spectral regimes.

We investigate the propagation properties and the radiation forces of a radially polarized Pearcey beam (RPPB) in uniaxial crystals analytically and numerically in this paper. Obtaining the propagation expression of an RPPB, we perform the intensity (in the x-direction, in the y-direction and in the synthesizing direction), the polarization direction, the energy flow and the angular momentum of an RPPB with the method of numerical calculation. The propagating properties of an RPPB in the free space are shown for comparison. The autofocusing and the inversion of an RPPB propagating in uniaxial crystals are demonstrated. The influence of the extraordinary refractive index and the ordinary refractive index on an RPPB in the uniaxial crystals is discussed.

Reconstruction of multiple objects from one hologram can be affected by the focus metric judgment of autofocusing. Various segmentation algorithms are applied to obtain a single object in the hologram. Each object is unambiguously reconstructed to acquire its focal position, which produces complicated calculations. Herein, Hough transform (HT)-based multi-object autofocusing compressive holography is presented. The sharpness of each reconstructed image is computed by using a focus metric such as entropy or variance. According to the characteristics of the object, the standard HT is further used for calibration to remove redundant extreme points. The compressive holographic imaging framework with a filter layer can eliminate the inherent noise in in-line reconstruction including cross talk noise of different depth layers, two-order noise, and twin image noise. The proposed method can effectively obtain 3D information on multiple objects and achieve noise elimination by only reconstructing from one hologram.