Perceptual Image Quality Of Launch Vehicle Imaging Telescopes,
2011
University of Central Florida
Perceptual Image Quality Of Launch Vehicle Imaging Telescopes, Joshua K. Lentz
Electronic Theses and Dissertations
A large fleet (in the hundreds) of high quality telescopes are used for tracking and imaging of launch vehicles during ascent from Cape Canaveral Air Force Station and Kennedy Space Center. A maintenance tool has been development for use with these telescopes. The tool requires rankings of telescope condition in terms of the ability to generate useful imagery. It is thus a case of ranking telescope conditions on the basis of the perceptual image quality of their imagery. Perceptual image quality metrics that are well-correlated to observer opinions of image quality have been available for several decades. However, these are …
Few-Cycle Pulses Amplification For Attosecond Science Applications Modeling And Experiments,
2011
University of Central Florida
Few-Cycle Pulses Amplification For Attosecond Science Applications Modeling And Experiments, Michael Hemmer
Electronic Theses and Dissertations
The emergence of mode-locked oscillators providing pulses with durations as short as a few electric-field cycles in the near infra-red has paved the way toward electric-field sensitive physics experiments. In addition, the control of the relative phase between the carrier and the pulse envelope, developed in the early 2000’s and rewarded by a Nobel price in 2005, now provides unprecedented control over the pulse behaviour. The amplification of such pulses to the millijoule level has been an on-going task in a few world-class laboratories and has triggered the dawn of attoscience, the science of events happening on an attosecond timescale. …
A Fibre Bragg Grating Sensor As A Receiver For Acoustic Communications Signals,
2011
Edith Cowan University
A Fibre Bragg Grating Sensor As A Receiver For Acoustic Communications Signals, Graham Wild, Steven Hinckley
Research outputs 2011
A Fibre Bragg Grating (FBG) acoustic sensor is used as a receiver for acoustic communications signals. Acoustic transmissions were generated in aluminium and Carbon Fibre Composite (CFC) panels. The FBG receiver was coupled to the bottom surface opposite a piezoelectric transmitter. For the CFC, a second FBG was embedded within the layup for comparison. We show the transfer function, frequency response, and transient response of the acoustic communications channels. In addition, the FBG receiver was used to detect Phase Shift Keying (PSK) communications signals, which was shown to be the most robust method in a highly resonant communications channel.
Optical Techniques In Experimental Physics,
2011
University of Alabama in Huntsville
Optical Techniques In Experimental Physics, Tomasz Lis
Summer Community of Scholars Posters (RCEU and HCR Combined Programs)
No abstract provided.
Characterization Of The Nonlinear Refractive Index Of Carbon Disulfide Over An Extended Spectral And Temporal Range,
2011
University of Central Florida
Characterization Of The Nonlinear Refractive Index Of Carbon Disulfide Over An Extended Spectral And Temporal Range, Marcus Seidel
Electronic Theses and Dissertations
The intensity dependent refractive index change of a medium is frequently described in terms of the product n₂ · I where n₂ is the nonlinear refractive index and I the light intensity. The nonlinear refractive index is often treated as constant which is a reasonable assumption if the light interacts only with bound electrons. In the case of carbon disulfide (CS₂) however, nuclear motions contribute to n₂. These motions occur on the sub picosecond time scale and thus become especially relevant for ultrashort laser pulses. The neat liquid CS₂ is studied because it exhibits a large nonlinear refractive index in …
Low Noise And Low Repetition Rate Semiconductor-Based Mode-Locked Lasers,
2011
University of Central Florida
Low Noise And Low Repetition Rate Semiconductor-Based Mode-Locked Lasers, Dimitrios Mandridis
Electronic Theses and Dissertations
The topic of this dissertation is the development of low repetition rate and low noise semiconductor-based laser sources with a focus on linearly chirped pulse laser sources. In the past decade chirped optical pulses have found a plethora of applications such as photonic analogto-digital conversion, optical coherence tomography, laser ranging, etc. This dissertation analyzes the aforementioned applications of linearly chirped pulses and their technical requirements, as well as the performance of previously demonstrated chirped pulse laser sources. Moreover, the focus is shifted to a specific application of the linearly chirped pulses, timestretched photonic analog-to-digital conversion (TS ADC). The challenges of …
Design, Fabrication, And Testing Of High-Transparency Deep Ultra-Violet Contacts Using Surface Plasmon Coupling In Subwavelength Aluminum Meshes,
2011
University of Central Florida
Design, Fabrication, And Testing Of High-Transparency Deep Ultra-Violet Contacts Using Surface Plasmon Coupling In Subwavelength Aluminum Meshes, Clarisse Mazuir
Electronic Theses and Dissertations
The present work aims at enhancing the external quantum efficiencies of ultra-violet (UV) sensitive photodetectors (PDs) and light emitting diodes (LEDs)for any light polarization. Deep UV solid state devices are made out of AlGaN or MgZnO and their performances suffer from the high resistivity of their p-doped regions. They require transparent p-contacts; yet the most commonly used transparent contacts have low transmission in the UV: indium tin oxide (ITO) and nickel-gold (Ni/Au 5/5 nms) transmit less than 50% and 30% respectively at 300 nm. Here we investigate the use of surface plasmons (SPs) to design transparent p-contacts for AlGaN devices …
In-Plane Sensitive Electronic Speckle Pattern Interferometer Using A Diffractive Holographic Optical Element,
2011
Technological University Dublin
In-Plane Sensitive Electronic Speckle Pattern Interferometer Using A Diffractive Holographic Optical Element, Raghavendra Jallapuram, Con Healy, Emilia Mihaylova, Vincent Toal
Articles
We describe a student project in electronic speckle pattern interferometry. The project includes holographic recording of diffraction gratings in thick, self-processing photopolymer layers made from off-the-shelf chemicals. The gratings are employed in a simple electronic speckle pattern interferometer to measure in-plane rotation.
Localized Surface Plasmon Resonance Of Single Silver Nanoparticles Studied By Dark-Field Optical Microscopy And Spectroscopy,
2011
Old Dominion University
Localized Surface Plasmon Resonance Of Single Silver Nanoparticles Studied By Dark-Field Optical Microscopy And Spectroscopy, Wei Cao, Tao Huang, Xiao-Hong Nancy Xu, Hani E. Elsayed-Ali
Electrical & Computer Engineering Faculty Publications
Localized surface plasmon resonance (LSPR) of Ag nanoparticles (NPs) with different shapes and disk-shaped Ag NP pairs with varying interparticle distance is studied using dark-field optical microscopy and spectroscopy (DFOMS). Disk-, square-, and triangular-shaped Ag NPs were fabricated on indium tin oxide-coated glass substrates by electron beam lithography. The LSPR spectra collected from single Ag NPs within 5×5 arrays using DFOMS exhibited pronounced redshifts as the NP shape changed from disk to square and to triangular. The shape-dependent experimental LSPR spectra are in good agreement with simulations using the discrete dipole approximation model, although there are small deviations in the …
Nonuniformity In Lattice Contraction Of Bismuth Nanoclusters Heated Near Its Melting Point,
2011
Old Dominion University
Nonuniformity In Lattice Contraction Of Bismuth Nanoclusters Heated Near Its Melting Point, A. Esmail, M. Abdel-Fattah, Hani E. Elsayed-Ali
Electrical & Computer Engineering Faculty Publications
The structural properties of bismuth nanoclusters were investigated with transmission high-energy electron diffraction from room temperature up to 525 ± 6 K. The Bi nanoclusters were fabricated by thermal evaporation at room temperature on transmission electron microscope grids coated with an ultrathin carbon film, followed by thermal and femtosecond laser annealing. The annealed sample had an average cluster size of ∼14 nm along the minor axis and ∼16 nm along the major axis. The Debye temperature of the annealed nanoclusters was found to be 53 ± 6 K along the [012] direction and 86 ± 9 K along the [110] …
Coupled Photonic Crystal Micro-Cavities With Ultra-Low Threshold Power For Stiumulated Raman Scattering,
2011
Old Dominion University
Coupled Photonic Crystal Micro-Cavities With Ultra-Low Threshold Power For Stiumulated Raman Scattering, Qiang Liu, Zhengbiao Ouyang, Sacharia Albin
Electrical & Computer Engineering Faculty Publications
We propose coupled cavities to realize a strong enhancement of the Raman scattering. Five sub cavities are embedded in the photonic crystals. Simulations through finite-difference time-domain (FDTD) method demonstrate that one cavity, which is used to propagate the pump beam at the optical-communication wavelength, has a Q factor as high as 1.254 × 108 and modal volume as small as 0.03μm3 (0.3192(λ/n)3). These parameters result in ultra-small threshold lasing power ~17.7nW and 2.58nW for Stokes and anti-Stokes respectively. The cavities are designed to support the required Stokes and anti-Stokes modal spacing in silicon. The proposed structure …
Precision Frequency Measurements With Interferometric Weak Values,
2010
University of Rochester
Precision Frequency Measurements With Interferometric Weak Values, David J. Starling, P. Ben Dixon, Andrew N. Jordan, John C. Howell
Mathematics, Physics, and Computer Science Faculty Articles and Research
We demonstrate an experiment which utilizes a Sagnac interferometer to measure a change in optical frequency of 129 ± 7 kHz/√Hz with only 2 mW of continuous-wave, single-mode input power. We describe the measurement of a weak value and show how even higher-frequency sensitivities may be obtained over a bandwidth of several nanometers. This technique has many possible applications, such as precision relative frequency measurements and laser locking without the use of atomic lines.
Nanoparticle Doped Photopolymer With Reduced Shrinkage For Holographic Recording,
2010
Technological University Dublin
Nanoparticle Doped Photopolymer With Reduced Shrinkage For Holographic Recording, Mohesh Moothanchery, Svetlana Mintova, Izabela Naydenova, Vincent Toal
Conference Papers
We demonstrate holographic recording with Si-MFI zeolite doped acrylamide based photopolymerfilm. The influence of silicate nanoparticles on photopolymer shrinkage has been studied and compared withshrinkage in undoped photopolymer layers The shrinkage of the material (1.03%) is significantly lower forrecording in Si-MFI zeolite nanoparticle doped samples than for undoped layers (1.77%).
Tunable Optical Delay In Doppler-Broadened Cesium Vapor,
2010
Air Force Institute of Technology
Tunable Optical Delay In Doppler-Broadened Cesium Vapor, Monte D. Anderson
Theses and Dissertations
Variable-delay tunable optical delay line or optical buffers are critical for the development of all-optical networks components as well as interferometry and analytic instruments. Recent research on slow light may hold the key for the development of the first practical tunable optical delay device. In this research the linear dispersion delay effects in an alkali vapor. The hyperfine relaxation observations present insight into the complex bleach wave dynamics during a high-intensity pulsed pump in DPAL systems.
Spatial Light Dilution As A Technique For Conversion Of Solar Energy To Algal Biomass,
2010
Utah State University
Spatial Light Dilution As A Technique For Conversion Of Solar Energy To Algal Biomass, Daniel J. Dye
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
A photobioreactor has been designed and developed to efficiently utilize solar irradiance through spatial dilution of sunlight. The concept of spatial light dilution is simple: incident sunlight is spread over a large surface area, thus reducing the photon flux density of the light. The implementation of this technique, however, is difficult. The reactor described within uses a new approach to spatial light dilution, utilizing recently-developed optical components to diffuse concentrated sunlight inside an algae culture. Preliminary productivity tests indicate a 2-3 fold increase in productivity per unit aperture (sunlight collection area) over a control reactor with direct-sunlight. Aperture productivity of …
Rapidly Reconfigurable Slow-Light System Based On Off-Resonant Raman Absorption,
2010
University of Rochester
Rapidly Reconfigurable Slow-Light System Based On Off-Resonant Raman Absorption, Praveen K. Vudyasetu, Ryan M. Camacho, John C. Howell
Mathematics, Physics, and Computer Science Faculty Articles and Research
We present a slow-light system based on dual Raman absorption resonances in warm rubidium vapor. Each Raman absorption resonance is produced by a control beam in an off-resonant Λ system. This system combines all optical control of the Raman absorption and the low-dispersion broadening properties of the double Lorentzian absorption slow light. The bandwidth, group delay, and central frequency of the slow-light system can all be tuned dynamically by changing the properties of the control beam. We demonstrate multiple pulse delays with low distortion and show that such a system has fast switching dynamics and thus fast reconfiguration rates.
Construction And Improvement Of A Scheffler Reflector And Thermal Storage Device,
2010
California Polytechnic State University - San Luis Obispo
Construction And Improvement Of A Scheffler Reflector And Thermal Storage Device, Jason Rapp
Physics
We constructed and successfully tested a 2 m2 parabolic dish solar concentrator (Scheffler Concentrator) to focus sunlight onto a stationary target. Present efforts are to decrease the construction complexity and cost of the concentrator. In order to store solar heat, we also constructed and are testing a thermal storage device made of sand (for thermal mass), and pumice (for insulation). Preliminary tests indicate thermal retention times of many hours. Present efforts are to increase accessible power, and structural integrity.
Development Of Acrylamide Based Photopolymer For Full Colour Display Holography,
2010
Technological University Dublin
Development Of Acrylamide Based Photopolymer For Full Colour Display Holography, Chakrapani Meka
Doctoral
Holography is a firmly established discipline that can be used as a tool for scientific and engineering studies and as a display medium as well. Until now both silver halide photographic emulsions (SHPE) and dichromated gelatine (DCG) have been the most common materials used for high efficiency full colour reflection hologram recording. However, these materials require wet chemical processing for developing the holograms which is laborious and costly from the point of view of commercial applications. Self-developing photopolymers such as acrylamide based photopolymer (ABP) which do not require development are the ideal choice for real-time recording and reconstruction of holograms. …
Characterization Of Pollen Particles Using Lidar,
2010
Utah State University
Characterization Of Pollen Particles Using Lidar, Leda Sox
Graduate Student Posters
We have observed pollen in the local troposphere using the depolarization capabilities of a LIDAR (Light Detection and Ranging) system. The polarization characteristics of the received LIDAR signal, along with supplemental pollen forecast data, allowed me to characterize the shape of the pollen particles.
Laser Demonstration And Performance Characterization Of An Optically Pumped Alkali Laser System,
2010
Air Force Institute of Technology
Laser Demonstration And Performance Characterization Of An Optically Pumped Alkali Laser System, Clifford V. Sulham
Theses and Dissertations
Diode Pumped Alkali Lasers (DPALs) offer a promising approach for high power lasers in military applications that will not suffer from the long logistical trails of chemical lasers or the thermal management issues of diode pumped solid state lasers. This research focuses on characterizing a DPAL-type system to gain a better understanding of using this type of laser as a directed energy weapon. A rubidium laser operating at 795 nm is optically pumped by a pulsed titanium sapphire laser to investigate the dynamics of DPALs at pump intensities between 1.3 and 45 kW/cm2. Linear scaling as high as …
