Single-shot deterministic complex amplitude imaging with a single-layer metalens

Science Advances, Journal Year: 2024, Volume and Issue: 10(1)

Published: Jan. 5, 2024

Conventional imaging systems can only capture light intensity. Meanwhile, the lost phase information may be critical for a variety of applications such as label-free microscopy and optical metrology. Existing retrieval techniques typically require bulky setup, multiframe measurements, or prior target scene. Here, we proposed an extremely compact system complex amplitude imaging, leveraging extreme versatility single-layer metalens to generate spatially multiplexed polarization phase–shifted point spread functions. Combining with camera, simultaneously record four shearing interference patterns along both in-plane directions, thus allowing deterministic reconstruction field in single shot. Using incoherent light-emitting diode illumination, experimentally demonstrated speckle-noise–free static moving objects tailored magnification ratio view. The miniaturized robust open door portable devices point-of-care applications.

Language: Английский

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Motion-resolved, reference-free holographic imaging via spatiotemporally regularized inversion

Optica, Journal Year: 2023, Volume and Issue: 11(1), P. 32 - 32

Published: Nov. 29, 2023

Holography is a powerful technique that records the amplitude and phase of an optical field simultaneously, enabling variety applications such as label-free biomedical analysis coherent diffraction imaging. Holographic recording without reference wave has been long pursued because it obviates high experimental requirements conventional interferometric methods. However, due to ill-posed nature underlying retrieval problem, reference-free holographic imaging faced with inherent tradeoff between fidelity temporal resolution. Here, we propose general computational framework, termed spatiotemporally regularized inversion (STRIVER), achieve motion-resolved, fidelity. Specifically, STRIVER leverages signal priors in spatiotemporal domain jointly eliminate ambiguities motion artifacts, and, when combined diversity measurement schemes, produces physically reliable, time-resolved video from series intensity-only measurements. We experimentally demonstrate near-field ptychography, where dynamic freely swimming paramecia performed at framerate-limited speed 112 fps. The proposed method can be potentially extended other spectral regimes, modalities, pushing resolution toward higher limits.

Language: Английский

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Physics-driven universal twin-image removal network for digital in-line holographic microscopy

Optics Express, Journal Year: 2023, Volume and Issue: 32(1), P. 742 - 742

Published: Nov. 24, 2023

Digital in-line holographic microscopy (DIHM) enables efficient and cost-effective computational quantitative phase imaging with a large field of view, making it valuable for studying cell motility, migration, bio-microfluidics. However, the quality DIHM reconstructions is compromised by twin-image noise, posing significant challenge. Conventional methods mitigating this noise involve complex hardware setups or time-consuming algorithms often limited effectiveness. In work, we propose UTIRnet, deep learning solution fast, robust, universally applicable suppression, trained exclusively on numerically generated datasets. The availability open-source UTIRnet codes facilitates its implementation in various systems without need extensive experimental training data. Notably, our network ensures consistency reconstruction results input holograms, imparting physics-based foundation enhancing reliability compared to conventional approaches. Experimental verification was conducted among others live neural glial culture migration sensing, which crucial neurodegenerative disease research.

Language: Английский

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Spatially‐Coded Fourier Ptychography: Flexible and Detachable Coded Thin Films for Quantitative Phase Imaging with Uniform Phase Transfer Characteristics

Advanced Optical Materials, Journal Year: 2024, Volume and Issue: 12(15)

Published: Feb. 7, 2024

Abstract Fourier ptychography (FP) is an enabling imaging technique that produces high‐resolution complex‐valued images with extended field coverages. However, when FP a phase object any specific spatial frequency, the captured contain only constant values, rendering recovery of corresponding linear ramp impossible. This challenge not unique to but also affects other common microscopy techniques — rather counterintuitive outcome given their widespread use in imaging. The underlying issue originates from non‐uniform transfer characteristic inherent microscope systems, which impedes conversion wavefields into discernible intensity variations. To address this challenge, spatially‐coded (scFP) presented for true quantitative In scFP, flexible and detachable coded thin film attached atop image sensor regular setup. modulation ensures uniform response across entire synthetic bandwidth. It improves reconstruction quality, corrects refractive index underestimation issues prevalent conventional FP, adds new dimension measurement diversity domain. development scFP expected catalyze research directions applications imaging, emphasizing need accuracy frequency response.

Language: Английский

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Emerging scientific and industrial applications of digital holography: an overview

Engineering Research Express, Journal Year: 2023, Volume and Issue: 5(3), P. 032005 - 032005

Published: Sept. 1, 2023

Abstract Holography is a technique to record and reconstruct three dimensional (3D) information without mandating lenses. Digital holography (DH) provides direct access the complex amplitude of reconstructed wavefront. This feature differentiates DH from other imaging techniques enables it provide quantitative object under investigation. Advancements in technologies digital image sensors, coherent sources, computation algorithms hardware, has paved way holographic systems for industrial applications. work presents an overview scientific applications where can play important role. Few areas including microscopy, non-destructive testing, displays, environment, cloud ocean studies are discussed.

Language: Английский

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Single-shot experimental-numerical twin-image removal in lensless digital holographic microscopy

Optics and Lasers in Engineering, Journal Year: 2023, Volume and Issue: 172, P. 107878 - 107878

Published: Oct. 7, 2023

Language: Английский

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Mueller-Gabor holographic microscopy

Optics and Lasers in Engineering, Journal Year: 2024, Volume and Issue: 178, P. 108191 - 108191

Published: March 22, 2024

Despite the emergence of various methods for Mueller matrix recovery, achieving complete volumetric retrieval remains a challenge. An alternative approach that leverages in-line Gabor holography to comprehensively extract polarization information from samples is introduced in this context. The proposed polarization-sensitive holographic setup enables recovery three-dimensional (3D) after numerical repropagation holographically rendered complex field sample planes. This proposal validated using calibrated birefringent test target, Calcium Oxalate crystals, and containing microplastics, providing 3D measurement polarimetric parameters such as diattenuation, polarizance, depolarization, retardance. results agree with those obtained through reference based on image-plane brightfield polarimetry. system sensitive axial variations within without any mechanical movement nor optical adjustments— an accomplishment elusive conventional non-holographic/interferometric systems. These findings emphasize versatility potential recovering intricate characteristics specimens, offering first imaging best authors' knowledge.

Language: Английский

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Lensless camera: Unraveling the breakthroughs and prospects

Fundamental Research, Journal Year: 2024, Volume and Issue: unknown

Published: March 1, 2024

Lensless imaging is an innovative and swiftly advancing technology at the intersection of optics, technology, computational science. It captures scene by directly recording interference or diffraction patterns light, subsequently utilizing algorithms to reconstruct original image from these patterns. upends traditional paradigms, offering newfound design flexibility capacity seamlessly integrate within diverse ecosystems. This paper aims provide overview significant developments in optical modulation elements, sensors, reconstruction algorithms. The novel application scenarios that benefit lensless are presented. opportunities challenges associated with camera discussed for further improving its performance.

Language: Английский

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Lensfree auto-focusing imaging with coarse-to-fine tuning method

Optics and Lasers in Engineering, Journal Year: 2024, Volume and Issue: 181, P. 108366 - 108366

Published: June 12, 2024

Language: Английский

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Flyscan terahertz multi-plane lensless imaging with suppressed coherent noise

Optics Express, Journal Year: 2025, Volume and Issue: 33(2), P. 2640 - 2640

Published: Jan. 3, 2025

Coherent lensless imaging usually suffers from coherent noise and twin-image artifacts. In the terahertz (THz) range, where wavelengths are 2 to 4 orders of magnitude longer than those in visible spectrum, manifests primarily as parasitic interference fringes edge diffraction, rather speckle noise. this work, suppress Fabry-Pérot (F-P) fringes, we propose a novel method, which involves averaging over multiple diffraction patterns that acquired at equal intervals within sample's half-wavelength axial shift. To address well non-uniform illumination, normalization operation is applied. As disturbances when dealing with single pattern, multi-plane configuration employed. With all these strategies combined, flyscan THz technique enables subwavelength resolution, high-quality, full-field, rapid complex-valued imaging. Furthermore, refine two algorithms for image reconstruction: one based on regular alternating projection other an optimization model total variation regularization. We experimentally verify proposed methods, achieving lateral resolution 88 µm (0.74λ) 2.52 THz, showcase its potential biomedical applications by section mouse brain tissue.

Language: Английский

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