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Articles 1 - 30 of 75
Full-Text Articles in Physics
Information-Rich 6d Single-Molecule Imaging Design Using Optimization, Tingting Wu
Information-Rich 6d Single-Molecule Imaging Design Using Optimization, Tingting Wu
McKelvey School of Engineering Theses & Dissertations
When studying biochemical processes, localizing the targets alone will not paint a complete picture. We also need techniques to probe how biomolecules interact with one another, including how molecules are organized into larger structures, how they are oriented with respect to surrounding molecules, and how local chemical parameters, like pH and hydrophobicity, vary spatially and temporally. My dissertation focuses on single-molecule orientation localization microscopy (SMOLM, Chapter 1). The objective is to develop imaging techniques for measuring how molecules are oriented with respect to their surrounding molecules, namely, 3D orientation. Achieving optimal imaging performance requires careful design of both the forward …
Volumetric Imaging Using The Pupil-Matched Remote Focusing Technique In Light-Sheet Microscopy, Sayed Hassan Dibaji Foroushani
Volumetric Imaging Using The Pupil-Matched Remote Focusing Technique In Light-Sheet Microscopy, Sayed Hassan Dibaji Foroushani
Optical Science and Engineering ETDs
ABSTRACT
The dissertation explores innovative techniques in light sheet microscopy, a pivotal tool in biomedical imaging, to enhance its speed, resolution, and efficiency in capturing dynamic biological processes. Light sheet microscopy allows for quick 3D imaging of biological specimens ranging from cells to organs with high spatiotemporal resolution, large field-of-view, and minimal damage, making it vital for in vivo imaging.
The first project introduces a novel optical concept designed to optimize Axially Swept Light Sheet Microscopy (ASLM). This technique is crucial for imaging specimens ranging from live cells to chemically cleared organs due to its versatility across different immersion media. …
Development Of An Optical Test Bed For The Fabrication And Characterisation Of An Analog Holographic Wavefront Sensor, Emma Branigan, Andreas Zepp, Suzanne Martin, Matthew Sheehan, Szymon Gladysz, Kevin Murphy
Development Of An Optical Test Bed For The Fabrication And Characterisation Of An Analog Holographic Wavefront Sensor, Emma Branigan, Andreas Zepp, Suzanne Martin, Matthew Sheehan, Szymon Gladysz, Kevin Murphy
Conference Papers
A new holographic recording setup has been developed for the fabrication of single- and multi-mode photopolymer-based analog holographic wavefront sensors. A second setup has been built and used to characterise the sensor at several wavelengths.
Radiation Exposure Calibration Of The Al2o3:C With Radium-226 And Cesium-137 Using The Osl Method, Selma Tepeli Aydin
Radiation Exposure Calibration Of The Al2o3:C With Radium-226 And Cesium-137 Using The Osl Method, Selma Tepeli Aydin
All Theses
Optically stimulated luminescence (OSL) dosimetry was utilized to calibrate Al2O3:C powder dosimeters, available commercially as the nanoDot® from Landauer Inc., and compare the dosimeter response to radium-226 (226Ra) and cesium-137 (137Cs). The signal from the OSL was quantified using a microSTARii® OSL reader also produced by Landauer Inc. Dose-response curves were developed for 226Ra and 137Cs experiments (5 dosimeters each) at thirteen absorbed doses. Individual dosimeter response was tracked by serial number. Linear regression analysis was performed to determine if there were significant differences between the intercepts of the …
Aspects Of Stochastic Geometric Mechanics In Molecular Biophysics, David Frost
Aspects Of Stochastic Geometric Mechanics In Molecular Biophysics, David Frost
All Dissertations
In confocal single-molecule FRET experiments, the joint distribution of FRET efficiency and donor lifetime distribution can reveal underlying molecular conformational dynamics via deviation from their theoretical Forster relationship. This shift is referred to as a dynamic shift. In this study, we investigate the influence of the free energy landscape in protein conformational dynamics on the dynamic shift by simulation of the associated continuum reaction coordinate Langevin dynamics, yielding a deeper understanding of the dynamic and structural information in the joint FRET efficiency and donor lifetime distribution. We develop novel Langevin models for the dye linker dynamics, including rotational dynamics, based …
Acoustically Levitated Whispering-Gallery Mode Microlasers, H. M. Reynoso-De La Cruz, E. D. Hernández-Campos, E. Ortiz-Ricardo, A. Martínez-Borquez, I. Rosas-Román, V. Contreras, G. Ramos-Ortiz, B. Mendoza-Santoyo, Cecilia Zurita-Lopez, R. Castro-Beltrán
Acoustically Levitated Whispering-Gallery Mode Microlasers, H. M. Reynoso-De La Cruz, E. D. Hernández-Campos, E. Ortiz-Ricardo, A. Martínez-Borquez, I. Rosas-Román, V. Contreras, G. Ramos-Ortiz, B. Mendoza-Santoyo, Cecilia Zurita-Lopez, R. Castro-Beltrán
Biology, Chemistry, and Environmental Sciences Faculty Articles and Research
Acoustic levitation has become a crucial technique for contactless manipulation in several fields, particularly in biological applications. However, its application in the photonics field remains largely unexplored. In this study, we implement an affordable and innovative phased-array levitator that enables stable trapping in the air of micrometer dye-doped droplets, thereby enabling the creation of microlasers. For the first time, this paper presents a detailed performance of the levitated microlaser cavity, supported by theoretical analysis concerning the hybrid technology based on the combination of whispering-gallery modes and acoustic fields. The pressure field distribution inside the acoustic cavity is numerically solved and …
System-Level Noise Performance Of Coherent Imaging Systems, Derek J. Burrell, Joshua H. Follansbee, Mark F. Spencer, Ronald G. Driggers
System-Level Noise Performance Of Coherent Imaging Systems, Derek J. Burrell, Joshua H. Follansbee, Mark F. Spencer, Ronald G. Driggers
Faculty Publications
We provide an in-depth analysis of noise considerations in coherent imaging, accounting for speckle and scintillation in addition to “conventional” image noise. Specifically, we formulate closed-form expressions for total effective noise in the presence of speckle only, scintillation only, and speckle combined with scintillation. We find analytically that photon shot noise is uncorrelated with both speckle and weak-to-moderate scintillation, despite their shared dependence on the mean signal. Furthermore, unmitigated speckle and scintillation noise tends to dominate coherent-imaging performance due to a squared mean-signal dependence. Strong coupling occurs between speckle and scintillation when both are present, and we characterize this behavior …
Quantitative, Photocurrent Multidimensional Coherent Spectroscopy, Adam Halaoui
Quantitative, Photocurrent Multidimensional Coherent Spectroscopy, Adam Halaoui
Electronic Theses and Dissertations
Multidimensional coherent spectroscopy (MDCS) is a quickly growing field that has a lot of advantages over more conventional forms of spectroscopy. These advantages all come from the fact that MDCS allows us to get time resolved correlated emission and absorption spectra using very precisely chosen interactions between the density matrix and the excitation laser. MDCS spectra gives the researcher a lot of information that can be extracted purely through qualitative analysis. This is possible because state couplings are entirely separated on the spectra, and once we know how to read the data, we can see how carriers transport in the …
Active-Illumination Extension To The Priest And Meier Pbrdf, Mark F. Spencer, Milo W. Hyde Iv, Santasri R. Bose-Pillai, Michael A. Marciniak
Active-Illumination Extension To The Priest And Meier Pbrdf, Mark F. Spencer, Milo W. Hyde Iv, Santasri R. Bose-Pillai, Michael A. Marciniak
Faculty Publications
This paper develops a 3D vector solution for the scattering of partially coherent laser-beam illumination from statistically rough surfaces. Such a solution enables a rigorous comparison to the well-known Priest and Meier polarimetric bidirectional reflectance distribution function (pBRDF) [Opt Eng 41(5),988 (2002).]. Overall, the comparison shows excellent agreement for the normalized spectral density and the degree of polarization. Based on this agreement, the 3D vector solution also enables an extension to the Priest and Meier pBRDF that accounts for the effects of active illumination. In particular, the 3D vector solution enables the development of a closed-form expression for the spectral …
Optics Studies For Multipass Energy Recovery At Cebaf: Er@Cebaf, Isurumali Neththikumara
Optics Studies For Multipass Energy Recovery At Cebaf: Er@Cebaf, Isurumali Neththikumara
Physics Theses & Dissertations
Energy recovery linacs (ERLs), focus on recycling the kinetic energy of electron beam for the purpose of accelerating a newly injected beam within the same accelerating structure. The rising developments in the super conducting radio frequency technology, ERL technology has achieved several noteworthy milestones over the past few decades. In year 2003, Jefferson Lab has successfully demonstrated a single pass energy recovery at the CEBAF accelerator. Furthermore, they conducted successful experiments with IR-FEL demo and upgrades, as well as the UV FEL driver. This multi-pass, multi-GeV range energy recovery demonstration proposed to be carried out at CEBAF accelerator at Jefferson …
Dynamics Of Spin And Charge Of Color Centers In Diamond Under Cryogenic Conditions, Richard G. Monge
Dynamics Of Spin And Charge Of Color Centers In Diamond Under Cryogenic Conditions, Richard G. Monge
Dissertations, Theses, and Capstone Projects
Individual quantum systems in semiconductors are currently the most sought-after platform for applications in quantum science. Most notably, the nitrogen-vacancy (NV) center in diamond features a defect deep within the electronic bandgap, making it amenable for precise manipulation to help pave the way to perform fundamental quantum physics experimentation. The NV center also offers long coherence times and versatile spin-dependent fluorescent properties, making it an ideal candidate for a nanoscale magnetometer. Furthermore, multi-color excitation offers deterministic charge state manipulation. While ambient operation has been key to their appeal, bringing NVs to cryogenic conditions opens new opportunities for alternate forms of …
Tunable Linear And Nonlinear Metasurfaces Based On Hybrid Gold-Graphene Plasmons, Matthew Feinstein
Tunable Linear And Nonlinear Metasurfaces Based On Hybrid Gold-Graphene Plasmons, Matthew Feinstein
Dissertations, Theses, and Capstone Projects
Optical Metasurfaces are planar structures that are patterned with subwavelength structures and are very thin compared to the wavelength of light. Despite their thinness, these structured materials can strongly interact with incident light to effect the functionalities of conventional optical components, such as rotation of the polarization state, beam steering, lensing, spectral filtering, and holography, to name a few. Metasurfaces can also facilitate nonlinear optical effects, such as the mixing of beams at different frequencies to generate a beam at a new frequency.
The ability to alter the behavior of a metasurface during operation is highly desired for applications such …
Nonlinear Processes In Room Temperature Exciton-Polaritons, Prathmesh Deshmukh
Nonlinear Processes In Room Temperature Exciton-Polaritons, Prathmesh Deshmukh
Dissertations, Theses, and Capstone Projects
Strong light-matter coupling in solid state systems is an intriguing process that allows one to exploit the advantages of both light and matter. In this context, microcavities have become essential platforms for studying the strong coupling regime, where hybrid light-matter states known as exciton-polaritons form, leading to enhanced light matter interaction, modified material properties, and novel quantum phenomena. In this thesis, we explore the phenomenology of exciton-polaritons in strained TMD microcavities, 2D perovskites, fluorescent proteins and organic dyes encompassing thermalization, polariton lasing, and the observation of nonlinear effects.
Transition metal dichalcogenides (TMDs) have emerged as a remarkable class of two- …
Design And Fabrication Of A Trapped Ion Quantum Computing Testbed, Christopher A. Caron
Design And Fabrication Of A Trapped Ion Quantum Computing Testbed, Christopher A. Caron
Masters Theses
Here we present the design, assembly and successful ion trapping of a room-temperature ion trap system with a custom designed and fabricated surface electrode ion trap, which allows for rapid prototyping of novel trap designs such that new chips can be installed and reach UHV in under 2 days. The system has demonstrated success at trapping and maintaining both single ions and cold crystals of ions. We achieve this by fabricating our own custom surface Paul traps in the UMass Amherst cleanroom facilities, which are then argon ion milled, diced, mounted and wire bonded to an interposer which is placed …
The Importance Of Contrast Sensitivity, Color Vision, And Electrophysiological Testing In Clinical And Occupational Settings, Frances Silva
The Importance Of Contrast Sensitivity, Color Vision, And Electrophysiological Testing In Clinical And Occupational Settings, Frances Silva
Theses & Dissertations
Visual acuity (VA) is universally accepted as the gold standard metric for ocular vision and function. Contrast sensitivity (CS), color vision, and electrophysiological testing for clinical and occupational settings are warranted despite being deemed ancillary and minimally utilized by clinicians. These assessments provide essential information to subjectively and objectively quantify and obtain optimal functional vision. They are useful for baseline data and monitoring hereditary and progressive ocular conditions and cognitive function. The studies in this dissertation highlight the value of contrast sensitivity, color vision, and cone specific electrophysiological testing, as well as the novel metrics obtained with potential practical clinical …
Design Of A Resonant Optical Cavity For Imaging Magneto-Optically Active Thin Film Samples, Cody Robert Brelage
Design Of A Resonant Optical Cavity For Imaging Magneto-Optically Active Thin Film Samples, Cody Robert Brelage
Graduate Theses - Physics and Optical Engineering
This document describes the design and fabrication of an optical resonator system to investigate magneto-optic properties of thin film samples. This system uses an open-air optical resonator to enable photons to make multiple passes through each thin film and thus increase the magnitude of the Faraday rotation that each sample imposes onto the light that exits the system. This system promises many future experiments to study the magneto-optic properties of thin film and nano-particle samples. Using an optical resonator to enhance Faraday rotation should enable an improved signal-to-noise ratio in taking measurements and images with a photodetector.
Super-Resolution Microscopy With Color Centers In Diamond, Forrest A. Hubert
Super-Resolution Microscopy With Color Centers In Diamond, Forrest A. Hubert
Optical Science and Engineering ETDs
This dissertation explores the development and application of diamond color centers, specifically the silicon-vacancy (SiV) and nitrogen-vacancy (NV) centers, in super-resolution microscopy and magnetic imaging techniques. It demonstrates the potential of SiV centers as photostable fluorophores in stimulated emission depletion (STED) microscopy, with a resolution of approximately 90 nm. The research also presents a method for nanoscale magnetic microscopy using NV centers by combining charge state depletion (CSD) microscopy with optically detected magnetic resonance (ODMR) to image magnetic fields produced by 30 nm iron-oxide nanoparticles. The individual magnetic feature width reaches ~100 nm while resolving magnetic field patterns from nanoparticles …
Fem Simulations Of Plasmon Field Enhancement In Gold Nanoparticle Dimers And Gold Nanoparticle-Nanorod Dimers, Edward J. Lipchus
Fem Simulations Of Plasmon Field Enhancement In Gold Nanoparticle Dimers And Gold Nanoparticle-Nanorod Dimers, Edward J. Lipchus
Graduate Masters Theses
Plasmon resonance refers to the collective oscillation of free electrons in a nanomaterial in response to an incident electromagnetic field. When two plasmonic nanoparticles are placed close together, their localized surface plasmon resonances can couple and interact. The resulting plasmonic coupling leads to the formation of new plasmonic modes in the dimer system, significantly enhancing the electromagnetic fields in the vicinity of the nanoparticles, with various interesting and potentially useful applications. This thesis investigates the optical field enhancement arising from gold nanoparticle dimers in an aqueous dielectric medium, using the Finite Element Method simulation software COMSOL Multiphysics. The simulations provide …
High-Power Laser Cooling And Temperature-Dependent Fluorescence Studies Of Ytterbium Doped Silica, Brian Topper
High-Power Laser Cooling And Temperature-Dependent Fluorescence Studies Of Ytterbium Doped Silica, Brian Topper
Optical Science and Engineering ETDs
Experimental observation of optical refrigeration using ytterbium doped silica glass in recent years has created a new solution for heat mitigation in high-power laser systems, nonlinear fiber experiments, integrated photonics, and precision metrology. Current efforts of different groups focus on compositional optimization, fiber fabrication, and investigating how much silica can be cooled with a laser. At the start of this work, the best effort in laser cooling ytterbium doped silica saw cooling by 6 K from room temperature. This dissertation follows the experimental efforts that culminated in the increase of this initial record by one order of magnitude. Comprehensive spectroscopic …
Hybridly Integrated Semiconductor Lasers And Amplifiers On Iii-V/Si3n4 Platform For Beam Combining And Other Advanced Applications, Siwei Zeng
All Dissertations
Photonic integrated circuits (PICs) are devices that integrate multiple photonic functions on a small chip and allow for accurate dimension control and massive production. Similar to electronic integrated circuits, PICs can significantly reduce the system cost, size, weight, and operation power (CSWaP). Recently, the PIC technology has transformed many optical technologies which traditionally rely on tabletop systems and bulky components, such as optical interconnects, nonlinear optics, and quantum photonics, into a chip-scale platform. This device and system miniaturization has successfully led to a wide range of practical applications in computing, sensing, spectroscopy, and communication. However, the traditional passive PIC platform …
Propagation Of Spatiotemporal Optical Vortex Beams In Linear, Second-Order Dispersive Media, Milo W. Hyde Iv, Miguel A. Porras
Propagation Of Spatiotemporal Optical Vortex Beams In Linear, Second-Order Dispersive Media, Milo W. Hyde Iv, Miguel A. Porras
Faculty Publications
In this paper, we study the behaviors of spatiotemporal optical vortex (STOV) beams propagating in linear dispersive media. Starting with the Fresnel diffraction integral, we derive a closed-form expression for the STOV field at any propagation distance z in a general second-order dispersive medium. We compare our general result to special cases published in the literature and examine the characteristics of higher-order STOV beams propagating in dispersive materials by varying parameters of the medium and source-plane STOV field. We validate our analysis by comparing theoretical predictions to numerical computations of a higher-order STOV beam propagating through fused silica, where we …
Wave Optics Approach To Solar Cell Brdf Modeling With Experimental Results, Madilynn Compean, Todd V. Small, Milo W. Hyde Iv, Michael Marciniak
Wave Optics Approach To Solar Cell Brdf Modeling With Experimental Results, Madilynn Compean, Todd V. Small, Milo W. Hyde Iv, Michael Marciniak
Faculty Publications
Light curve analysis is often used to discern information about satellites in geosynchronous orbits. Solar panels, comprising a large part of the satellite’s body, contribute significantly to these light curves. Historically, theoretical bidirectional reflectance distribution functions (BRDFs) have failed to capture key features in the scattered light from solar panels. In recently published work, a new solar cell BRDF was developed by combining specular microfacet and “two-slit” diffraction terms to capture specular and periodic/array scattering, respectively. This BRDF was experimentally motivated and predicted many features of the solar cell scattered irradiance. However, the experiments that informed the BRDF were limited …
Enhanced Acousto-Optic Properties Of Silicon Carbide Based Layered Structure, Namrata Dewan Soni
Enhanced Acousto-Optic Properties Of Silicon Carbide Based Layered Structure, Namrata Dewan Soni
Al-Bahir Journal for Engineering and Pure Sciences
This study investigates the feasibility of using silicon carbide-based layered surface acoustic wave (SAW) devices in acousto-optic applications. The acousto-optic properties of the temperature-stable layered structure TeO3/SiC/128oY-X LiNbO3 are investigated through theoretical analysis. This analysis includes the evaluation of key parameters such as the overlap integral, figure of merit, and diffraction efficiency. The SAW propagation characteristics and field profiles required for these calculations are obtained using SAW software. Results show that the layered structure has high diffraction efficiency of nearly 96% and a promising value for the acousto-optic figure of merit, indicating potential use in low driving power acousto-optic devices. …
Entanglement In The Hawking Effect: From Astrophysical To Optical Black Holes, Dimitrios Kranas
Entanglement In The Hawking Effect: From Astrophysical To Optical Black Holes, Dimitrios Kranas
LSU Doctoral Dissertations
The Hawking effect is an exciting physical prediction lying at the intersection of the two most successful theories of the past century, namely, Einstein’s theory of relativity and quantum mechanics. In this dissertation, we put special emphasis on the quantum aspects of the Hawking process encoded in the entanglement shared by the emitted fluxes of created quanta. In particular, we employ sharp tools from quantum information theory to quantify the entanglement produced by the Hawking effect throughout the black hole evaporation process. Our framework allows us to extend previous calculations of entanglement to a larger set of cases, for instance, …
Size Effect On The Optical Response Of Cylindrical Palladium Nanoparticles, Salem Marhaba, Mohammed Khalaf
Size Effect On The Optical Response Of Cylindrical Palladium Nanoparticles, Salem Marhaba, Mohammed Khalaf
BAU Journal - Science and Technology
In this work, a computational study is carried out to investigate the optical response of palladium nano-cylinders. The Finite Element Method (FEM) is employed using the COMSOL MULTIPHYSICS simulation program to calculate the scattering, absorption, and extinction cross-sections. The influence of the size of the cylindrical nanoparticles on their optical properties is discussed. The results are plotted for a broad spectral range of wavelengths from ultra-violet to infra-red of the incident electromagnetic wave on the cylindrical nanoparticles.
Adaptive Plasmonic Metasurfaces For Radiative Cooling And Passive Thermoregulation, Azadeh Didari-Bader, Nooshin M. Estakhri, Nasim Mohammadi Estrakhri
Adaptive Plasmonic Metasurfaces For Radiative Cooling And Passive Thermoregulation, Azadeh Didari-Bader, Nooshin M. Estakhri, Nasim Mohammadi Estrakhri
Engineering Faculty Articles and Research
In this work, we investigate a class of planar photonic structures operating as passive thermoregulators. The radiative cooling process is adjusted through the incorporation of a phase change material (Vanadium Dioxide, VO2) in conjunction with a layer of transparent conductive oxide (Aluminum-doped Zinc Oxide, AZO). VO2 is known to undergo a phase transition from the “dielectric” phase to the “plasmonic” or “metallic” phase at a critical temperature close to 68°C. In addition, AZO shows plasmonic properties at the long-wave infrared spectrum, which, combined with VO2, provides a rich platform to achieve low reflections across the …
Optical Characterisation Of Holographic Diffusers And Bangerter Foils For Treatment Of Amblyopia, Matthew Hellis, Suzanne Martin, Matthew Sheehan, Kevin Murphy
Optical Characterisation Of Holographic Diffusers And Bangerter Foils For Treatment Of Amblyopia, Matthew Hellis, Suzanne Martin, Matthew Sheehan, Kevin Murphy
Articles
Amblyopia is a significant issue for children worldwide, and current treatment methods have drawbacks that can hinder treatment effectiveness and/or patient experience. This study proposes a new treatment method using holographic diffusers while also comparing their optical characteristics to a current treatment method (Bangerter foils). Holographic diffusers were developed by optically patterning thin polymer layers on a micron scale. Two compositions of photopolymer (acrylamide and diacetone acrylamide based) are analysed herein. Characterisation shows that holographic diffusers of either composition can achieve a wide range of on-axis intensity reductions, allowing for precise and customisable treatment levels by altering recording exposure time …
Measuring The Pulse Duration Of A Femtosecond Laser Using Intensity Autocorrelation, Ross N. Relic
Measuring The Pulse Duration Of A Femtosecond Laser Using Intensity Autocorrelation, Ross N. Relic
Macalester Journal of Physics and Astronomy
In this experiment, an intensity autocorrelator is set up in order to measure the pulse duration of a passively mode-locked Titanium-Sapphire laser with a power of 267mW producing femtosecond pulses. Then this measurement, as well as a measurement of the laser’s spectrum, is used to test the Uncertainty Principle. Intensity autocorrelation is a well-established technique for measuring pulse duration, and is among the more intuitive techniques for this purpose, which is why it was selected for this experiment. The experimental setup was computerized. The delay of one half of the pulse was controlled by a motorized translation stage which was …
Characterization Of Boreal-Arctic Vegetation Growth Phases And Active Soil Layer Dynamics In The High-Latitudes Of North America: A Study Combining Multi-Year In Situ And Satellite-Based Observations, Michael G. Brown
Dissertations, Theses, and Capstone Projects
This dissertation examined the seasonal freeze/thaw activity in boreal-Arctic soils and vegetation physiology in Alaska, USA and Alberta, Canada, using in situ environmental measurements and passive microwave satellite observations. The boreal-Arctic high-latitudes have been experiencing ecosystem changes more rapidly in comparison to the rest of Earth due to the presently warming climatic conditions having a magnified effect over Polar Regions. Currently, the boreal-Arctic is a carbon sink; however, recent studies indicate a shift over the next century to become a carbon source. High-latitude vegetation and cold soil dynamics are influenced by climatic shifts and are largely responsible for the regions …
Modelling Hoe Performance With An Extended Source; Experimental Investigation Using Misaligned Point Sources, Jorge Lasarte, Kevin Murphy, Izabela Naydenova, Jesús Atencia, Mª Victoria Collados, Suzanne Martin
Modelling Hoe Performance With An Extended Source; Experimental Investigation Using Misaligned Point Sources, Jorge Lasarte, Kevin Murphy, Izabela Naydenova, Jesús Atencia, Mª Victoria Collados, Suzanne Martin
Conference Papers
Holographic Optical Elements (HOEs) have the potential to enable more compact, versatile and lightweight optical designs, but many challenges remain. Volume HOE’s have the advantage of high diffraction efficiency but they present both chromatic selectivity and chromatic dispersion which impact on their use with wide spectrum light sources. Single-colour LED sources have a narrow spectrum that reduces these issues and this makes them better suited for use with volume HOEs. However, the LED source size must be taken into consideration for compact volume HOE-LED systems. To investigate the design limits for compact HOE-LED systems, a theoretical and experimental study was …