An ultracompact underwater pulsed digital holographic camera with rapid particle image extraction suite

Acknowledgement The authors are very grateful to DASA (Defence and Security Accelerator, UK) for funding the project (Contract No: DSTLX100013220).Peer reviewe

A real-time digital holographic microscope with an optical tweezer

The most significant advantage of the holographic microscopy is being able to image transparent objects such as biological cells without staining. Therefore, the cell image can be captured while it is alive. Moreover, Manipulating a living cell without destructing it’s structure can be achieved by the use of an optical tweezer which apply a pulling force around a tightly focused laser beam without a physical contact. Therefore, an instrument that combines the holographic microscope and the optical tweezer is quite useful for biological studies. Another advantage of holographic imaging is that, one does not need to do mechanical focusing for the scene when recording the hologram. Focusing is achieved by reconstructing the hologram at a certain depth. If the object’s optical depth from the recording plane is not known a priori, auto-focusing algorithms must be used to estimate this distance. However, auto-focusing and reconstruction can be quite time consuming as the hologram sizes increase and the microscope can not operate in real-time with high resolution holograms using traditional central processing units (CPUs). Therefore, for real-time operation, additional hardware accelerators are required for reconstructing high resolution holograms. A holograms can be reconstructed tens of times faster with a graphics processing unit than with the state-of-the-art main CPUs. In this thesis, an auto-focusing megapixel-resolution digital holographic microscope (DHM) that uses a commodity graphics card as the calculation engine is presented. The computational power of the GPU allows the DHM to work in realtime such that the reconstruction distance is estimated unsupervised, and the postprocessing of the hologram is transparent to the user. Performances of the DHM under GPU and CPU settings are presented and a maximum of 70 focused reconstructions per second (frps) are achieved with 1024 ⇥ 1024 pixels holograms. Moreover, a setup for incorporating an optical tweezer to the holographic microscope is provided. With this setup, it is possible to trap small particles while performing holographic imaging

Review : Deep learning in electron microscopy

Deep learning is transforming most areas of science and technology, including electron microscopy. This review paper offers a practical perspective aimed at developers with limited familiarity. For context, we review popular applications of deep learning in electron microscopy. Following, we discuss hardware and software needed to get started with deep learning and interface with electron microscopes. We then review neural network components, popular architectures, and their optimization. Finally, we discuss future directions of deep learning in electron microscopy

Artificial Intelligence in Classical and Quantum Photonics

The last decades saw a huge rise of artificial intelligence (AI) as a powerful tool to boost industrial and scientific research in a broad range of fields. AI and photonics are developing a promising two-way synergy: on the one hand, AI approaches can be used to control a number of complex linear and nonlinear photonic processes, both in the classical and quantum regimes; on the other hand, photonics can pave the way for a new class of platforms to accelerate AI-tasks. This review provides the reader with the fundamental notions of machine learning (ML) and neural networks (NNs) and presents the main AI applications in the fields of spectroscopy and chemometrics, computational imaging (CI), wavefront shaping and quantum optics. The review concludes with an overview of future developments of the promising synergy between AI and photonics

Digital Image Processing

This book presents several recent advances that are related or fall under the umbrella of 'digital image processing', with the purpose of providing an insight into the possibilities offered by digital image processing algorithms in various fields. The presented mathematical algorithms are accompanied by graphical representations and illustrative examples for an enhanced readability. The chapters are written in a manner that allows even a reader with basic experience and knowledge in the digital image processing field to properly understand the presented algorithms. Concurrently, the structure of the information in this book is such that fellow scientists will be able to use it to push the development of the presented subjects even further

Polarized Light Applications towards Biomedical Diagnosis and Monitoring

Utilization of polarized light for improved specificity and sensitivity in disease diagnosis is occurring more often in fields of sensing, measurement, and medical diagnostics. This dissertation focuses on two distinct areas where polarized light is applied in biomedical sensing/monitoring: The first portion of worked reported in this dissertation focuses on addressing several major obstacles that exist prohibiting the use of polarized light as a means of developing an optical based non-invasive polarimetric glucose sensor to improve the quality of life and disease monitoring for millions of people currently afflicted by diabetes mellitus. In this work there are two key areas, which were focused on that require further technical advances for the technology to be realized as a viable solution. First, in vivo studies performed on New Zealand White (NZW) rabbits using a dual-wavelength polarimeter were conducted to allow for performance validation and modeling for predictive glucose measurements accounting for the time delay associated with blood aqueous humor glucose concentrations in addition to overcoming motion induced birefringence utilizing multiple linear regression analysis. Further, feasibility of non-matched index of refraction eye coupling between the system and corneal surface was evaluated using modeling and verified with in vitro testing validation. The system was initially modeled followed by construction of the non-matched coupling configuration for testing in vitro. The second half of the dissertation focuses on the use of polarized light microscopy designed, built, and tested as a low-cost high quality cellphone based polarimetric imaging system to aid medical health professionals in improved diagnosis of disease in the clinic and in low-resource settings. Malaria remains a major global health burden and new methods for, low-cost, high-sensitivity diagnosis of malaria are needed particularly in remote low-resource areas throughout the world. Here, a cost effective optical cell-phone based transmission polarized light microscope system is presented utilized for imaging the malaria pigment known as hemozoin. Validation testing of the optical resolution required to provide diagnosis similar to commercial polarized imaging systems will be conducted and the optimal design will be utilized in addition to image processing to improve the diagnostic capability

Advances in Sonar Technology

The demand to explore the largest and also one of the richest parts of our planet, the advances in signal processing promoted by an exponential growth in computation power and a thorough study of sound propagation in the underwater realm, have lead to remarkable advances in sonar technology in the last years.The work on hand is a sum of knowledge of several authors who contributed in various aspects of sonar technology. This book intends to give a broad overview of the advances in sonar technology of the last years that resulted from the research effort of the authors in both sonar systems and their applications. It is intended for scientist and engineers from a variety of backgrounds and even those that never had contact with sonar technology before will find an easy introduction with the topics and principles exposed here

Proceedings of the International Workshop on Medical Ultrasound Tomography: 1.- 3. Nov. 2017, Speyer, Germany

Ultrasound Tomography is an emerging technology for medical imaging that is quickly approaching its clinical utility. Research groups around the globe are engaged in research spanning from theory to practical applications. The International Workshop on Medical Ultrasound Tomography (1.-3. November 2017, Speyer, Germany) brought together scientists to exchange their knowledge and discuss new ideas and results in order to boost the research in Ultrasound Tomography

NASA Tech Briefs, February 1992

Topics covered include: New Product Development; Electronic Components and Circuits; Electronic Systems; Physical Sciences; Materials; Computer Programs; Mechanics; Machinery; Fabrication Technology; Mathematics and Information Sciences; Life Sciences