Article
Optics
Wei LI, Bingjian Wang, Tengfei Wu, Feihu Xu, Xiaopeng Shao
Summary: Lensless scattering imaging is a prospective approach to microscopy that reconstructs high-resolution images of objects from measured speckle patterns, providing a solution when imaging optics cannot be used. This study proposes two general approaches that enable single-shot lensless scattering imaging under broadband illumination, with both noninvasive and invasive modes. The methods are experimentally verified using visible radiation and have potential applications in ultrafast science, passive sensing, and biomedical applications.
PHOTONICS RESEARCH
(2022)
Article
Optics
Jiawei Sun, Jiachen Wu, Song Wu, Ruchi Goswami, Salvatore Girardo, Liangcai Cao, Jochen Guck, Nektarios Koukourakis, Juergen W. Czarske
Summary: Quantitative phase imaging is a label-free technique that provides morphology and quantitative biophysical information in biomedicine. We have developed a computational lensless microendoscope using an ultra-thin bare multi-core fiber which enables high resolution and sensitivity quantitative phase imaging, offering potential clinical applications for in vivo pathological diagnosis.
LIGHT-SCIENCE & APPLICATIONS
(2022)
Editorial Material
Optics
Jian Zhao, Mingsheng Li
Summary: The integration of an acousto-optic programmable dispersive filter with spectrally filtered sequentially time all-optical mapping photography enables independent control of frame rate, frame intensity, and exposure time with a simple system design.
LIGHT-SCIENCE & APPLICATIONS
(2022)
Article
Mechanics
Sierra Legare, Andrew Grace, Marek Stastna
Summary: Direct numerical simulations reveal the presence of unique double-diffusive instabilities in narrow horizontal domains, influenced by boundaries and exhibiting complex time evolution, which can drive localized mixing in highly confined settings.
Review
Optics
Vivek Boominathan, Jacob T. Robinson, Laura Waller, Ashok Veeraraghavan
Summary: This article reviews recent advances in lensless imaging technology and describes the design principles to be considered when developing and using lensless imaging systems.
Article
Optics
Ferreol Soulez, Manon Rostykus, Christophe Moser, Michael Unser
Summary: This paper presents a reconstruction method to recover high-resolution images of the phase and amplitude of a sample with an extrapolated field of view from aliased intensity measurements taken at a lower resolution.
Article
Engineering, Electrical & Electronic
Xiangjun Yin, Huanjing Yue, Mengxi Zhang, Huihui Yue, Xingyu Cui, Jingyu Yang
Summary: This paper proposes an end-to-end lensless object inference network and designs three phases to acquire features, highlight object regions, and eliminate false features. In addition, it also constructs the first dataset for lensless object inference research.
IEEE TRANSACTIONS ON COMPUTATIONAL IMAGING
(2022)
Article
Engineering, Electrical & Electronic
Yucheng Zheng, M. Salman Asif
Summary: Mask-based lensless cameras are suitable for novel designs of computational imaging systems due to their flat, thin, and light-weight nature. However, the quality of images reconstructed from these cameras is often poor. In this paper, we propose the use of coded illumination patterns to improve the image reconstruction quality. We designed and tested different illumination patterns and found that shifting dots patterns provide the best overall performance. We also present simulation and hardware experiments results to demonstrate the effectiveness of our proposed method.
IEEE TRANSACTIONS ON COMPUTATIONAL IMAGING
(2023)
Article
Optics
Xiuxi Pan, Tomoya Nakamura, Xiao Chen, Masahiro Yamaguchi
Summary: A preliminary lensless inference camera specialized for object recognition, the LLI camera, performs computationally efficient data preprocessing through a new approach called local binary patterns map generation, enhancing robustness to local disturbances and enabling real-time inference.
Article
Optics
Yuchen Ma, Jiachen Wu, Shumei Chen, Liangcai Cao
Summary: Mask-based lensless cameras offer flexible imaging systems by breaking the constraints of traditional lens-based cameras. However, the limitations of imaging devices result in low reconstruction quality. To address this challenge, we propose an explicit-restriction convolutional framework that effectively incorporates multiple constraints by introducing linear and nonlinear terms. By customizing the framework, better image quality or higher pixel density can be achieved.
Article
Optics
Yinger Zhang, Zhouyi Wu, Yunhui Xu, Jiangtao Huangfu
Summary: A lensless camera replaces the lens with a mask, reducing thickness, weight, and cost. A parallel dual-branch fusion model is proposed, investigating the advantages and disadvantages of model-based and data-driven reconstruction methods. The model extracts features from both branches for better reconstruction, and a novel network architecture is introduced for enhanced data-driven branch. The superiority of the dual-branch fusion model is verified through comparison with other methods on a public dataset.
Article
Optics
Mohamed Touil, Said Idlahcen, Rezki Becheker, Denis Lebrun, Claude Roze, Ammar Hideur, Thomas Godin
Summary: This paper introduces a versatile single-shot imaging technique that combines STAMP, AOPDF, and DIH to improve imaging speed and enhance system flexibility. AOPDF allows for flexible adjustment of parameters, while DIH enables reconstruction on a wide depth of field. The system's imaging speed and flexibility are demonstrated by visualizing ultrashort events.
LIGHT-SCIENCE & APPLICATIONS
(2022)
Article
Optics
Mahmoud E. Khani, Zachery B. Harris, Mengkun Liu, M. Hassan Arbab
Summary: This work presents a novel computational technique for creating spatially- and spectrally-resolved chemical maps through a diffusive cloak using terahertz time-domain spectroscopy. The technique utilizes the maximal overlap discrete wavelet transform to obtain a multiresolution spectral decomposition of THz extinction coefficients and introduces a new spectroscopic concept called the bimodality coefficient spectrum.
Article
Computer Science, Information Systems
Thuong Nguyen Canh, Trung Thanh Ngo, Hajime Nagahara
Summary: Lensless imaging protects visual privacy by capturing heavily blurred images that are imperceptible for humans but contain enough information for machines. We propose a learnable lensless imaging framework that balances privacy protection and recognition accuracy through the use of specific loss functions. We studied the impact of privacy protection on personal identification through subjective evaluation and validated our simulation with a hardware realization of lensless imaging.
Article
Optics
Hao Zhu, Zhen Liu, You Zhou, Zhan Ma, Xun Cao
Summary: Lensless imaging is a reliable method for observing microscopic scenes and has various applications. We propose a novel unsupervised Diffractive Neural Field (DNF) method that accurately characterizes the imaging process and achieves precise reconstruction of complex fields using limited measurements. Simulation and experimental results show the superior performance and potential of the proposed method.
Article
Biochemical Research Methods
Philipp Zelger, Lisa Bodner, Martin Offterdinger, Lukas Velas, Gerhard J. Schuetz, Alexander Jesacher
Summary: This study examines the precise spatial localization of single molecules in three dimensions and compares various techniques for improving localization performance. It is found that off-focus microscopy and biplane imaging can achieve the best performance in close proximity to the coverslip.
BIOMEDICAL OPTICS EXPRESS
(2021)
Article
Optics
Franziska Strasser, Simon Moser, Monika Ritsch-Marte, Gregor Thalhammer
Summary: Optical tweezers are a powerful tool for manipulating particles on the microscale, allowing detailed investigations into mechanical properties of biological systems. The holographic force measurement method presented in this study can simultaneously measure all components of the force applied to a specific particle, without needing information about the particle's size, shape, or optical properties. This opens up new opportunities for localized quantitative force measurements in complex biological settings.
Article
Mathematics, Applied
Clemens Kirisits, Michael Quellmalz, Monika Ritsch-Marte, Otmar Scherzer, Eric Setterqvist, Gabriele Steidl
Summary: This paper investigates the mathematical imaging problem of optical diffraction tomography for a scenario involving a microscopic rigid particle rotating in a trap created by acoustic or optical forces. The study shows that the problem can be solved using an efficient non-uniform discrete Fourier transform.
Article
Multidisciplinary Sciences
Molly A. May, Nicolas Barre, Kai K. Kummer, Michaela Kress, Monika Ritsch-Marte, Alexander Jesacher
Summary: Scattering in biological tissues is a major hindrance for in vivo optical imaging, but wavefront shaping has shown promise in overcoming this challenge. The authors introduced an algorithm called DASH, which utilizes holographic phase stepping interferometry to quickly update phase information after each measurement, leading to rapid improvement in wavefront correction. This method achieved a significant increase in signal enhancement compared to previous technologies after just one measurement iteration.
NATURE COMMUNICATIONS
(2021)
Article
Optics
Nicolas Barre, Alexander Jesacher
Summary: Graded-index optical elements can shape light precisely and in specific ways. Recent advances in laser manufacturing offer possibilities for realizing three-dimensional graded-index volumes. This study presents an algorithmic approach for computing these elements, along with suitable cost functions for different designs.
Article
Optics
Nicolas Barre, Alexander Jesacher
Summary: We present an algorithmic approach for holographic shaping of partially coherent light, which can achieve individually optimized transformation for each mode using gradient descent and algorithmic differentiation.
Article
Multidisciplinary Sciences
Fabian Hinterer, Magdalena C. Schneider, Simon Hubmer, Montserrat Lopez-Martinez, Philipp Zelger, Alexander Jesacher, Ronny Ramlau, Gerhard J. Schuetz
Summary: Single molecule localization microscopy (SMLM) has the potential to resolve structural details of biological samples at the nanometer scale. By performing SMLM under cryogenic temperature, higher localization precision can be achieved. However, it is important to consider the anisotropic emission characteristics of dipole emitters with fixed orientation to fully exploit the resolution. This study demonstrates the use of astigmatic imaging and dipole orientation information to extract the position of dipole emitters without bias and reach a precision of 1 nm.
Article
Physics, Multidisciplinary
Franziska Strasser, Stephen M. Barnett, Monika Ritsch-Marte, Gregor Thalhammer
Summary: We propose a method to measure the optical torque applied to particles of arbitrary shape using the change of angular momentum of light. The method allows for the determination of all torque components from a single interference pattern and the retrieval of the required phase using an iterative algorithm. This method provides access to the torque pertaining to individual particles as well as separate spin or orbital parts of the total torque.
PHYSICAL REVIEW LETTERS
(2022)
Article
Chemistry, Multidisciplinary
Frederik Maiwald, Clemens Roider, Michael Schmidt, Stefan Hierl
Summary: Optical coherence tomography is a valuable tool for inspecting weld seams in polymer parts and has great potential for process monitoring in the optical and medical industries. This study proposes a novel method using optical coherence tomography to determine the location and size of weld seams, achieving accurate and reliable results.
APPLIED SCIENCES-BASEL
(2022)
Article
Physics, Multidisciplinary
Maximilian Sohmen, Molly A. May, Nicolas Barre, Monika Ritsch-Marte, Alexander Jesacher
Summary: Adaptive optics (AO) is a powerful tool for increasing the imaging depth of multiphoton scanning microscopes. Dynamic Adaptive Scattering compensation Holography (DASH) is a fast-converging sensorless AO technique used for scatter compensation. This study investigates the performance of DASH under different turbidity conditions.
FRONTIERS IN PHYSICS
(2022)
Article
Optics
Bangshan Sun, Fyodor Morozko, Patrick S. Salter, Simon Moser, Zhikai Pong, Raj B. Patel, Ian A. Walmsley, Mohan Wang, Adir Hazan, Nicolas Barre, Alexander Jesacher, Julian Fells, Chao He, Aviad Katiyi, Zhen-Nan Tian, Alina Karabchevsky, Martin J. Booth
Summary: This paper reports a new method for femtosecond laser writing of optical-fiber-compatible glass waveguides, which enables high precision and low loss control of waveguide cross-sections. The fabricated waveguides show high refractive index contrast, low propagation loss, and low coupling loss, and they can operate across a broad range of wavelengths.
LIGHT-SCIENCE & APPLICATIONS
(2022)
Article
Materials Science, Multidisciplinary
Lisa Ackermann, Clemens Roider, Kristian Cvecek, Michael Schmidt
Summary: Phase-only beam shaping with a spatial light modulator (SLM) is a powerful tool in laser materials processing. Methods for mitigating speckle noise in tailored beam profiles, including averaging of speckled profiles and direct generation of uniform profiles, have been proposed. A direct comparison of these two methods is essential for practical applications.
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
(2022)
Article
Optics
Simon Moser, Alexander Jesacher, Monika Ritsch-Marte
Summary: Optical Diffraction Tomography (ODT) is a label-free method to quantitatively estimate the 3D refractive index (RI) distributions of microscopic samples. A new and robust multi-slice model is proposed to efficiently model the tomographic image formation for strongly scattering objects illuminated over a wide range of angles, resulting in reconstructions of higher fidelity compared to conventional methods. Rigorous solutions to Maxwell's equations are used as ground truth for testing.
Article
Biochemical Research Methods
Maximilian Sohmen, Juan D. Munoz-Bolanos, Pouya Rajaeipour, Monika Ritsch-Marte, Caglar Ataman, Alexander Jesacher
Summary: Adaptive optics combined with multi-photon techniques allows for deep imaging of specimens. However, most current adaptive optics schemes rely on reflective or diffractive wavefront modulators, which can be a limitation. In this study, we present a sensorless adaptive optics scheme that is adapted for transmissive wavefront modulators. We demonstrate its effectiveness in scatter correction of two-photon-excited fluorescence images and benchmark it against a liquid-crystal spatial light modulator.
BIOMEDICAL OPTICS EXPRESS
(2023)
Article
Biochemical Research Methods
Mia Kvale Lovmo, Benedikt Pressl, Gregor Thalhammer, Monika Ritsch-Marte
Summary: Recent advancements in cell biology research have shown that suspended cell clusters, such as organoids or cancer spheroids, have greater potential compared to traditional 2D cell cultures. However, sample confinement has been found to significantly impact cell clusters, leading to a demand for contact-less tools for 3D manipulation and inspection. This study introduces a reconfigurable, hybrid sono-optical system for contact-free 3D manipulation and imaging, suitable for biological samples in liquid suspension.
