| Optical Quality of High-Power Laser Beams in Lenses |
31-Oct-2008 |
34 pages |
| Authors:
Phillip Sprangle; Joseph Penano; Bahman Hafizi; Antonio Ting; Philip Serafim; Richard Fischer; NAVAL RESEARCH LAB WASHINGTON DC BEAM PHYSICS BRANCH
|
 | We analyze the propagation of a high-power laser beam through a lens and calculate the optical beam quality resulting from geometrical aberrations and thermal nonlinearities. We present a general ray optics formulation, including diffraction effects, for propagation through a nonlinear medium. An analytical expression for the beam quality parameter M2 is derived that includes the lowest-order effects of geometrical and thermal aberrations in a thin lens. A ray optics simulation ... |
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| Using Streamlines to Visualize Acoustic Energy Flow Across Boundaries |
01-Jul-2008 |
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| Authors:
David M Chapman; DEFENCE RESEARCH AND DEVELOPMENT ATLANTIC DARTMOUTH (CANADA)
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 | For spherical waves that radiate from a point source in a homogeneous fluid and propagate across a plane boundary into a dissimilar homogeneous fluid, the acoustic field may differ significantly from the geometric acoustic approximation if either the source or receiver is near the interface in acoustic wavelengths or if the stationary phase path is near the critical angle. In such cases, the entire acoustic field must be considered, including ... |
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| Real-Time Terahertz Imaging Using a Quantum Cascade Laser and Uncooled Microbolometer Focal Plane Array |
01-Jun-2008 |
101 pages |
| Authors:
Barry N Behnken; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| Real-time imaging in the terahertz (THz) spectral range was achieved using an uncooled, 160 120 pixel infrared microbolometer camera and a milliwatt-scale quantum cascade laser (QCL). By replacing the camera's original focusing optics with a Tsurupica-based lens and minimizing diffraction effects incurred by the QCL output beam, an imaging scheme was developed in which the camera's focal plane array successfully detected wavelengths that are more than an order of magnitude ... |
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| Modeling of SBS Phase Conjugation in Multimode Step Index Fibers |
01-Mar-2008 |
106 pages |
| Authors:
Justin B Spring; AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH GRADUATE SCHOOL OF ENGINEERING AND MANAGEMENT
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| Stimulated Brillouin scattering in a multimode step-index fiber can be used to generate a counter-propagating, phase-conjugate beam that would prove useful in applications such as near diffraction limited, double-pass high-power amplifiers or coherent beam combination. Little modeling of such a fiber-based phase-conjugator has been done, making it difficult to make decisions about the right fiber to use. A numerical model was constructed with the aim of providing educated predictions about ... |
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| A Refractive-Diffractive Element Design for Resonant Scanner Angular Correction: The Symmetric Beam Retardation Approach (Preprint) |
18-Jan-2008 |
31 pages |
| Authors:
Bahareh Haji-saeed; Jed Khoury; John Kierstead; Charles L Woods; AIR FORCE RESEARCH LAB HANSCOM AFB MA SENSORS DIRECTORATE
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| We propose a new approach for designing diffractive optical corrective elements with zooming capability to convert nonlinear sinusoidal scanning into linear scanning. Such devices will be useful for linearizing the angular scan of a resonant mirror scanner. The design methodology is to create a graded index of refraction device as the reference design, with its index of refraction parameters based on beam retardation through propagation in an inhomogeneous media. In ... |
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| Collection Efficiencies of Various Airborne Spray Flux Samplers Used in Aerial Application Research |
Jan-2008 |
11 pages |
| Authors:
W C Hoffmann; Bradley K Fritz; AGRICULTURAL RESEARCH SERVICE GAINESVILLE FL CENTER FOR MEDICAL AGRICULTURAL AND VETERINARY ENTOMOLOGY
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| A low air speed, spray dispersion tunnel was constructed and used to evaluate the collection efficiency of passive spray flux collectors. The dispersion tunnel utilizes an air-assisted nozzle to generate a spray cloud with a D(V0.5) of 18.5 (+/- 0.4 microns) at air speeds ranging from 0.4?4.0 m/s. A sampling protocol was developed to minimize spray flux and air speed variation effects while providing a check on theoretical collection efficiency ... |
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| Design of the Transmission Electron Microscope (TEM) Sampler Scriber Template as Developed to Improve and Simplify the Sample Preparation Procedure |
OCT 2007 |
28 pages |
| Authors:
Wendy L. Sarney; ARMY RESEARCH LAB ADELPHI MD
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| The image quality and visibility of the crystal planes in a TEM sample directly relate to how we initially cleave the wafer during the sample preparation process. For diffraction-contrast imaging, many defects and other crystalline features are orientation specific, and are only visible along certain zone axes. The resolution limits of the TEM dictate the preferred zone axes for phase-contrast imaging. The TEM Sample Scribing Template described here allows easy ... |
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| Unusual Nature of NanoDomains in Ultrahigh Temperature Polymer Derived Ceramics |
25 SEP 2007 |
12 pages |
| Authors:
Rishi Raj; COLORADO UNIV AT BOULDER DEPT OF MECHANICAL ENGINEERING
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| This grant has the objective of explaining the unusual properties of polymer-derived-ceramics (PDCs), so called because they are made directly from cross-linked polymers by controlled pyrolysis. The PDCs have unusual properties: (i) They remain structurally and chemically stable up to 1500 degrees C, (ii) They are amorphous in Bragg diffraction although small-angle-x ray-scattering shows the presence of nanodomains, (iii) POCs do NOT show steady state creep despite their amorphous structure, ... |
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| Studies with Laser Cooled Atoms and Single Molecules |
SEP 2007 |
20 pages |
| Authors:
Steven Chu; STANFORD UNIV CA
|
| We have achieved milestones in atom interferometry. By using multiphoton Bragg diffraction to make beam splitters that transfer the momentum of up to 24 photons to the atoms, we are able to increase the signal by a factor of 12 for Mach-Zehnder or 144 for Ramsey-Borde Interferometers relative to the 2-photon beam splitters used in the best present interferometers. We are also able to run Ramsey-Borde interferometers simultaneously to suppress ... |
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| Shoaling of Aguadilla Harbor, Puerto Rico |
JUN 2007 |
196 pages |
| Authors:
Steven A. Huges; Lyndell Z. Hales; ENGINEER RESEARCH AND DEVELOPMENT CENTER VICKSBURG MS COASTAL AND HYDRAULICS LAB
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| During construction of the Aguadilla Harbor, Puerto Rico, breakwater (June 1993 through July 1995), shoaling of the harbor was observed, and excessive wave heights in the harbor caused by refraction/diffraction were much larger than expected. Following construction, additional shoaling occurred even with only limited wave activity, and significantly excessive harbor shoaling occurred. The source of the harbor-shoaling sand was not known with certainty. The quantity of sediment deposited in the ... |
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| Homeland Security Enforcement Using Novel Terahertz Technology II |
12 MAY 2007 |
4 pages |
| Authors:
Adrian Dobroiu; RIKEN SENDAI (JAPAN)
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| The work focused on (1) improving detection limit using terahertz (THz) inspection method for higher sensitivity by developing better sources, detectors, and optical design, (2) testing powder detection for moving objects, (3) detecting effects of wave diffraction on envelope edges, and (4) evaluation of the terahertz wave penetration depth in metals and other materials. |
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| Stimulated Photorefractive Backscatter Leading to Six-Wave Mixing and Phase Conjugation in Iron Doped Lithium Niobate (Preprint) |
APR 2007 |
25 pages |
| Authors:
D. R. Evans; M. A. Saleh; P. P. Banerjee; J. Carns; G. Cook; AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH MATERIALS AND MANUFACTURING DIRECTORATE
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| Oblique incidence of a 532 nm pump on LiNbO3:Fe, nominally propagating along the +c axis, produces six waves through two-wave coupling (self diffraction) and four-wave mixing (parametric diffraction). One of these waves, the stimulated photorefractive backscatter, contains the self-phase conjugate. The dynamics of six-wave mixing and their dependence on crystal parameters and angle of incidence are analyzed. A novel order analysis of the interaction equations provides further insight into experimental ... |
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| Infrared-Sensitive Photorefractive Polymer Composite Devices |
28 MAR 2007 |
29 pages |
| Authors:
Nasser N. Peyghambarian; PURDUE UNIV LAFAYETTE IN SCHOOL OF MECHANICAL ENGINEERING
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| The main goal of the effort was to develop high performing photorefractive (PR) polymer composites working at 1 micrometer by one photon photorefractivity and two photon photorefractive devices operating at 1.5 micrometers. The utilization of these photorefractive devices for beam cleanup and reconstruction of aberrated images was also an important objective of the effort. We have accomplished these goals by developing highly efficient one photon sensitive photorefractive devices operating at ... |
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| Nanoporous Polymeric Grating-Based Optical Biosensors (Preprint) |
MAR 2007 |
21 pages |
| Authors:
Vincent K. Hsiao; John R. Waldeisen; Pamela F. Lloyd; Timothy J. Bunning; Tony J. Huang; PENNSYLVANIA STATE UNIV UNIVERSITY PARK DEPT OF ENGINEERING SCIENCE AND MECHANICS
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| This paper demonstrates a label-free biological sensing method using nanoporous polymer gratings. The high index modulation (0.07) of the nanoporous polymer grating structure generates a high signal-to-noise ratio, making the structure an ideal label-free biodetection platform. The fabrication process of the nanoporous polymeric grating involves holographic interference patterning and a functionalized pre-polymer syrup that facilitates the immobilization of biomolecules onto the polymeric sensor surface. The performance of the nanoporous polymeric ... |
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| Nonhydrostatic Numerical Investigations of Oscillating Flow over Sills: Generation of Internal Tides and Solitary Waves |
25 JAN 2007 |
3 pages |
| Authors:
Shenn-Yu Chao; MARYLAND UNIV CAMBRIDGE CENTER FOR ENVIRONMENTAL SCIENCE
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| The goal of this project is to identify processes relevant to the finite-amplitude, internal solitary waves observed in the region from the Luzon Strait to the Chinese continental shelf in support of ONR's Nonlinear Internal Waves Initiative (NLIW). A nonhydrostatic numerical model was adapted to study these waves. Wave generation by a ridge, propagation in the deep basin, and reflection and diffraction by an island were successfully simulated by the ... |
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| Characterization of Truck-Mounted Atomization Equipment Typically Used in Vector Control |
Jan-2007 |
10 pages |
| Authors:
W C Hoffmann; T W Walker; B K Fritz; T Gwinn; V L Smith; D Szumlas; Y Lan; D E Martin; J A Barber; TEXAS A AND M UNIV COLLEGE STATION COLL OF AGRICULTURE
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| The control of medically important arthropod vectors of human and animal disease is a high priority for both public health and military officials. Because droplet size of pesticide spray material is a critical factor affecting vector control applications, the droplet-size spectra produced by 11 sprayers and 3 spray formulations were evaluated. Droplet-size spectra were measured by a laser diffraction instrument, a hot-wire system, and rotating slides. There were considerable differences ... |
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| Liquid Crystal Bragg Gratings: Dynamic Optical Elements for Spatial Light Modulators (Preprint) |
JAN 2007 |
18 pages |
| Authors:
Richard L. Sutherland; Vincent P. Tondiglia; Lalgudi V. Natarajan; Jeremy M. Wofford; Stephen Siwecki; Gary Cook; Dean R. Evans; Pamela F. Lloyd; Timothy J. Bunning; AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH SURVIVABILITY AND SENSOR MATERIALS DIV/HARDENED MATERIALS
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| Bragg gratings yield a single diffracted order when irradiated by a coherent beam at the appropriate Bragg angle. In many cases, nearly all of the energy of the incident beam can be coupled to the diffracted beam. Hence these gratings can form many useful optical elements, and this has been realized in 1-D, 2-D, and 3-D photonic crystals. Bragg gratings made with liquid crystals offer the added dimension of dynamic ... |
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| Adaptive Optoelectronic Eyes: Hybrid Sensor/Processor Architectures |
13 NOV 2006 |
126 pages |
| Authors:
Jr. Tanguay Armand R.; B. K. Jenkins; Christoph von der Malsburg; Bartlett Mel; Irving Biederman; John O'Brien; Anupam Madhukar; UNIVERSITY OF SOUTHERN CALIFORNIA LOS ANGELES
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| The goal of this research program was to develop novel algorithms, architectures, and hardware for a truly smart camera, with inherent capability for semi-autonomous object recognition as well as optimal image capture. In this research, we combined striking advances in the understanding of the mechanisms of biological vision systems with similar advances in hybrid electronic/photonic packaging technology, in order to develop adaptive, artificial, biologically-inspired vision systems. A key research program ... |
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| Numerical Solution of the Extended Nonlinear Schrodinger Equation |
SEP 2006 |
199 pages |
| Authors:
John V. Harvey; JR Medina Richard L.; L3 COMMUNICATIONS TITAN CORP SAN ANTONIO TX
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| High-resolution mathematical models of the extended nonlinear Schroedinger equation have been designed which include diffraction combined with non-zero second-order group-velocity dispersion (GVD). These models follow a Gaussian pulse as it propagates in air to a large distance (several meters). With diffraction disabled, a pulse quickly collapses to a single singularity on the propagation axis. Alternatively, with diffraction included, a pulse will collapse into a pair of fins off the propagation ... |
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| Appropriate Measures and Consistent Standard for High Energy Laser Beam Quality (Postprint) |
01 AUG 2006 |
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| Authors:
T. S. Ross; William P. Latham; AIR FORCE RESEARCH LAB KIRTLAND AFB NM DIRECTED ENERGY DIRECTORATE
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| Along with power output of the laser system, laser optical quality or beam quality provides a suitable measure of performance. Power and beam quality are standards for the comparison of laser systems with each other and against mission requirements. An understanding of the meaning of beam quality is necessary to completely define laser performance capability. The current state of our community includes a multitude of different and not well understood ... |
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| Advanced Propagation Model (APM) Analysis of VHF Signals in the Southern California Desert |
01 AUG 2006 |
40 pages |
| Authors:
A. E. Barrios; K. D. Anderson; Ge. E. Lindem; SPACE AND NAVAL WARFARE SYSTEMS COMMAND SAN DIEGO CA
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| This report analyzes very high frequency signal strength data from two Naval Oceanic & Atmospheric Administration weather radio transmitters located in southern California and southwestern Arizona over a wide range of topography ranging from relatively flat to mountainous terrain. Meteorological information was obtained from local radiosonde measurement stations at Miramar (NKX) and Yuma Proving Ground (1Y7). These data are used as the basis for a validation study of the Advanced ... |
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| Radio Path Prediction Software for Command and Control Scenario Developers |
JUN 2006 |
43 pages |
| Authors:
Michael Shattuck; ARMY TRADOC ANALYSIS COMMAND WHITE SANDS MISSILE RANGE NM
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| In recent years, there has been great interest in incorporating the modeling of communication systems into combat simulations. However, development of supporting software tools for command and control (C2) scenario developers has not kept pace with the progress in combat simulation software. Scenario developers cannot easily experiment with alternate locations for base station repeaters/switches nor can they easily predict in advance where mobile platforms will experience communication failure. This information ... |
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| New Generation Materials and Structures for Nanophotonics and Nanoelectronics |
30 APR 2006 |
102 pages |
| Authors:
Paras N. Prasad; STATE UNIV OF NEW YORK COLL AT BUFFALO
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| This DURINT project produced high impact technical accomplishments. The notable accomplishments include building (i) new nanostructures, (ii) study of optoelectronic and magnetic properties, and (iii) fabrication of polymer based non-linear based photonic crystals and photonic circuitry, and (iv) fabrication of photodetctor as well as diffraction grating devices. On the preparation front, a modular colloidal route was devised to produce nano-heterostructures by integrating plasmonic (Au), magnetic (Fe3O4) and semiconducting (PbS or ... |
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| Transurethral Ultrasound Diffraction Tomography |
MAR 2006 |
27 pages |
| Authors:
Matthias C. Schabel; Dilip G. Roy; Altaf Khan; UTAH UNIV SALT LAKE CITY
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| The potential for cost-effective tomographic imaging using ultrasound continues to be confronted with difficulties arising from the computational complexity of fully three dimensional object reconstruction in the diffraction regime. Development of fast and accurate forward and inverse models for ultrasound propagation in the biomedical frequency range of 1-10 MHz is essential for diffraction tomography to be a practical imaging modality. We have implemented a flexible, object-oriented simulation system in MATLAB ... |
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| High Resolution Non-Contact Thermal Characterization Semiconductor Devices |
2006 |
8 pages |
| Authors:
James Christofferson; Daryoosh Vashaee; Ali Shakouri; Philip Melese; Jack Baskin; CALIFORNIA UNIV SANTA CRUZ SCHOOL OF ENGINEERING
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| Non-contact optical methods can be used for sub micron surface thermal characterization of active semiconductor devices. Point measurements were first made, and then real time thermal images were acquired with a specialized PINarray detector. This method of thermal imaging can have spatial resolution better than the diffraction limit of an infrared camera and can work in a wide range of ambient temperatures. The experimentally obtained thermal resolution is on the ... |
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| Magnetization Reversal in an Fe Film with an Array of Elliptical Holes on a Square Lattice |
2006 |
9 pages |
| Authors:
I. Guedes; M. Grimsditch; V. Metlushko; P. Vavassori; R. Camley; B. Ilic; P. Neuzil; R. Kumar; COLORADO UNIV AT COLORADO SPRINGS
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| The reversal mechanism for the magnetization in an Fe film with an array of elliptical holes is investigated using the diffracted magneto-optic Kerr effect (D-MOKE) technique. D-MOKE results are obtained as a function of temperature and the angle between the applied magnetic field and an ellipse axis. The transverse and longitudinal magnetization components and minor magnetization loops are also explored in order to understand the reversal process. The experimental results ... |
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| High-Frequency Electromagnetic Propagation/Scattering Codes |
31 DEC 2005 |
160 pages |
| Authors:
MONOPOLE RESEARCH THOUSAND OAKS CA
|
| The objective of our effort was to develop computational methods for constructing high-frequency asymptotic solutions in scattering on perfectly conducting objects. The emphasis of the first stage of our work was to describe high frequency phenomena in terms of numerically implemented evolution of wavefronts associated with the propagating waves. The wavefront evolution algorithm is implemented for the leading high frequency mechanisms including: free-space propagation, reflection on smooth surfaces, wave-front splitting ... |
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| Development Of Optically-Addressed Liquid Crystal Spatial Light Modulators (OA SLM) Operating In Reflective Mode With Diameter 50 Mm Using A-Si:C:H Photoconductors And Nematic And Ferroelectric Liquid Crystals |
17 OCT 2005 |
21 pages |
| Authors:
Vladimir A. Berenberg; INSTITUTE FOR LASER PHYSICS SAINT PETERSBURG (RUSSIA)
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| This report results from a contract tasking Research Institute for Laser Physics as follows: The goals of the project are to develop the technology for and master the replication of rewritable holographic devices (optically-addressed liquid crystal spatial light modulators, OA LC SLMs) to be used for real-time correction of optical distortions in imaging optical systems. SLMs using both nematic and ferrroelectric LCs are promising for use as correctors in imaging ... |
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| Plasmonic Devices and Materials |
30 JUN 2005 |
10 pages |
| Authors:
Harry A. Atwater; CALIFORNIA INST OF TECH PASADENA
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| This final technical report reviews our scientific and technical development in the area of new plasmonic devices and material undertaken during our AFOSR support from July 2002-June 2005. This report contains a summary overview of scientific and technical progress and results over the entire program. It also provides detail about recent technical conducted during Period of the present grant. Our work since the inception of the program has focused on ... |
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| Propagation and Performance Analysis for a 915 MHz Wireless IR Image Transfer System |
JUN 2005 |
97 pages |
| Authors:
Oktay Felekoglu; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
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| A 915 MHz wireless IR image transfer system, comprised of an IR-160 Thermal Camera and MDS iNet 900 transceivers, was assessed for image transfer capabilities in different environments. Image transfer through natural and artificial obstruction, the capability of transferring images under urban environments, and an exploration of interference issues associated with RF communication links were investigated in detail. Concrete, wood, various construction materials, and building walls were examined to assess ... |
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| Image Processing for Tactical UAV |
01 MAY 2005 |
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| Authors:
M. Broekaert; D. Duclos; M. Sirieix; SAGEM PARIS (FRANCE)
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| Outline: SAGEM Tactical UAVs; Imagery chain; 3rd generation IR imaging payload; Image processing; Automatic target recognition; Target localization; Conclusions. |
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| Mathematical Fluid Dynamics of Store and Stage Separation |
MAY 2005 |
226 pages |
| Authors:
Norman D. Malmuth; V. Shalaev; A. Fedorov; ROCKWELL SCIENTIFIC CO THOUSAND OAKS CA
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| To address the foregoing needs, the part of our research dealing with multi-body interactions we performed research to study store interaction with cavity bay shear layers relevant to separation and delivery with emphasis on the following tasks: 1. Continue combined asymptotic and numerical modeling of store separation and multibody flow processes 2. Investigate shock interactions relevant to stage separation 3. Develop combined dynamics and aerodynamic models for analysis of store ... |
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| Position-Adaptive UAV Radar for Urban Environments |
14 APR 2005 |
7 pages |
| Authors:
Atindra K. Mitra; AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH
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| A bistatic radar concept is presented where a low-altitude UAV (Unmanned Aerial Vehicle) "position-adaptively" converges to line-of-sight (LOS) locations for objects that are embedded between buildings. The concept is developed by deriving approximate electromagnetic signal models based on the uniform theory of diffraction (UTD). In addition, a new signature exploitation technique is formulated that allows for the estimation of target parameters in cases when neither the transmitting nor the receiving ... |
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| Integrated Wide-Band Millimeter Wave Imaging System |
22 DEC 2004 |
19 pages |
| Authors:
Dennis W. Prather; DELAWARE UNIV NEWARK DEPT OF ELECTRICAL AND COMPUTER ENGINEERING
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| In this project, we developed and demonstrated the design, fabrication, and experimental characterization of a millimeter wave imaging system. To achieve these goals we employed our electromagnetic modeling expertise to design and refine the system specifications. A novel two-element all-diffractive millimeter wave imaging system has been implemented to significantly reduce the overall size and weight of the system while maintaining mission criteria. We also set up a new and dedicated ... |
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| Theory and Measurements of Angle-of-Arrival of Diffraction-Limited Electromagnetic Wave Beams in the Turbulent Atmosphere |
DEC 2004 |
3 pages |
| Authors:
R. W. McMillan; R. A. Smith; E. J. Holder; J. C. Kerce; ARMY SPACE AND MISSILE DEFENSE COMMAND HUNTSVILLE AL
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| Improvements in radar tracking performance based on the use of interferometric and distributed aperture radar systems, together with the need for command-guided weapons for cost reduction, have placed more stringent requirements on radar angular accuracy. The result of this upgraded accuracy requirement is that fluctuations in angle-of-arrival (AOA) due to small-scale atmospheric turbulence become significant in the error budgets of command-guided weapons systems. In this paper we present a theory ... |
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| High-Order Accuracy Methods for the Modeling and Design of Microoptics and Photonic Devices |
30 NOV 2004 |
7 pages |
| Authors:
Jan S. Hesthaven; BROWN UNIV PROVIDENCE RI DIV OF APPLIED MATHEMATICS
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| The goals of this effort have been the development of high-order accurate computational methods for wave problems in general and Maxwell's equations of electromagnetics in particular. The applications are general, but particular emphasis has been on optical applications. The authors have made substantial progress in the development and application of three different methods: time-domain, high-order finite difference embedding methods; boundary variation methods for multilayered optics; and discontinuous Galerkin methods for ... |
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| Propagation of High-Power, Femtosecond Laser Radiation through the Atmosphere |
19 OCT 2004 |
56 pages |
| Authors:
Alexander Zemlyanov; EUROPEAN OFFICE OF AEROSPACE RESEARCH AND DEVELOPMENT FPO NEW YORK 09510
|
| This report results from a contract tasking the Institute of Atmospheric Optics, Siberian Branch, as follows: the contractor will investigate theoretically the interaction between femtosecond propagation effects and atmospheric turbulence, supercontinuum emission (spectral broadening), nonlinear scattering by atmospheric aerosols, and theoretical upper and lower limits for nonlinear propagation effects. The specific project objectives are as follows: (1) The theoretical study of powerful femtosecond laser pulse filamentation in the turbulent atmosphere; ... |
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| Phase Conjugation for High Energy Lasers (CD-ROM) |
15 SEP 2004 |
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| Authors:
Boris Zeldovich; UNIVERSITY OF CENTRAL FLORIDA ORLANDO SCHOOL OF OPTICS/CREOL
|
| ELECTRONIC FILE CHARACTERISTICS: 1,028 total files; .PDF, .PPT., .DOC, .JGP image, .MDB database, and Audio Video Interleave (.AVI). PHYSICAL DESCRIPTION: 2 computer laser optical discs (CD-ROMs); 4 3/4 in. ea.; 281.5 total MB. SYSTEMS DETAIL NOTE: ABSTRACT: Compiling the commented and annotated Database of publications on Phase Conjugation. As of now, Database is based on standard software "Microsoft Access 2000". Later versions of "Microsoft Access" are also suitable for ... |
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| Research in Electromagnetic Scattering and Phase Space Methods in Radiation Propagation |
01 SEP 2004 |
9 pages |
| Authors:
Arthur D. Yaghjian; DEVANEY (A J) ASSOCIATES BOSTON MA
|
| This document constitutes a final report for our research in electromagnetic scattering during the years 2001-2003. The technical research accomplishments during each year divide conveniently into the areas of basic electromagnetic theory, scattering-matrix analysis of antenna arrays, and surface integral equations. Significant contributions were also made in the area of incremental length diffraction coefficients and toward the development of the Air Force cylindrical near-field scanning facility for measuring bistatic RCS. ... |
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| Stability and Transient Effects in Ultraviolet Filaments |
SEP 2004 |
135 pages |
| Authors:
Thomas A. Niday; ARIZONA UNIV TUCSON OPTICAL SCIENCES CENTER
|
| Short, high intensity laser pulses induce nonlinear optical effects in the atmosphere that have the potential to make them propagate for long distances. Applications for long distance propagation of short pulses include active spectral remote sensing and laser lightning control. Much of the work in this field has been done with infrared pulses; however, it has been proposed that ultraviolet pulses have the advantage that longer pulse lengths can be ... |
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| Appendage and Viscous Forces for Ship Motions in Waves |
SEP 2004 |
|
| Authors:
Kevin A. McTaggart; DEFENCE RESEARCH AND DEVELOPMENT ATLANTIC DARTMOUTH (CANADA)
|
| This report describes the prediction of appendage and viscous forces in Defence Research and Development Canada (DRDC) Atlantic's ShipMo3D library for ship motions in waves. Previously, the ShipMo3D library considered only hull forces due to potential flow. Inclusion of appendage and viscous forces is essential for accurate prediction of ship sway, roll, and yaw motions. Appendage forces are caused by added mass, lift, and viscous effects. Hull viscous forces are ... |
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| Beam Clean-Up and Combining via Stimulated Scattering in Liquid Crystals |
10 AUG 2004 |
23 pages |
| Authors:
I. V. Ciapurin; L. B. Glebov; C. Tsai; M. C. Stickley; B. Y. Zeldovich; UNIVERSITY OF CENTRAL FLORIDA ORLANDO SCHOOL OF OPTICS/CREOL
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| Orientational stimulated scattering from o-wave into e-wave in liquid crystal may combine coherent beams or modes of amplifier(s) into diffraction- limited output. In experiment a 1000 micron liquid crystal layer transmitted undistorted o-wave with low attenuation. |
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| Fabri-Perot Spectral Filter that Preserves Image |
10 AUG 2004 |
|
| Authors:
H. V. Sarkissian; Boris Zeldovich; UNIVERSITY OF CENTRAL FLORIDA ORLANDO SCHOOL OF OPTICS/CREOL
|
| In some cases of active illumination of the target, high-resolution spectral selection may be used for discrimination between targets moving with different velocities and having different chemical compositions. Most monochromators and various spectrographs limit spatial and angular spread of input light, and thus distort the image. Volume diffraction grating at normal incidence may be used for spectral selection. However, spectral resolution delta v (1/cm) is about 1/L (i.e., limited by ... |
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| Implementation of 3D Angular Selective Achromatic Diffraction Optical Grating Device |
10 AUG 2004 |
17 pages |
| Authors:
L. Glebov; V. Smirnov; N. Tabirian; B. Zeldovich; UNIVERSITY OF CENTRAL FLORIDA ORLANDO SCHOOL OF OPTICS/CREOL
|
| Angular Selective Achromatic Diffraction Optical Grating (ASADOG) device has been implemented. Surface reflective grating had 1200 lines per mm. Two identical volume holograms were implemented using Photo-Thermo- Refractive (PTR) glass technology, with spatial frequency 1697 lines per mm. Sequential diffraction of incident light by surface grating by first volume grating and then by second one oriented at 90 degrees resulted in angular selection of incident beam, completely achromatic within the ... |
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| Quasicrystalline Films for Tribological Applications: Role of Stoichiometry Microstructure Transformation Kinetics and Oxide Structure and Chemistry |
30 JUN 2004 |
48 pages |
| Authors:
David Palaith; TECHNOLOGY ASSESSMENT AND TRANSFER INC ANNAPOLIS MD
|
| Significant progress was made towards an understanding of phase development and oxidation in the AlCuFe quasicrystalline system. Microstructure analysis by synchrotron diffraction exhibited the route for phase formation from the as-deposited precursor films. Formation of the R-phase occurred at 450 degree, below the previously published value of 475 degree. Preferential oxidation occurs in the near-surface region and temporarily disrupts formation of the R-phase microstructure, despite encapsulation in argon atmosphere. Fluctuation ... |
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| Advanced Fabrication and Characterization of Quantum and Nanophotonic Devices and Systems |
30 JUN 2004 |
23 pages |
| Authors:
Y. Fainman; CALIFORNIA UNIV REGENTS SAN DIEGO LA JOLLA CA
|
| The program completed its acquisition of equipment for the Micro- Fabrication Facility. The facility is used for fabrication of Quantum and Nanophotonic devices and consists of a CAIBE system capable of sub- micron resolution anisotropic (i.e. high aspect-ratio) etching and a RIE refurbished by INTELVAC Inc. A major capability is a facility for near field complex amplitude characterization with nanoscale spatial and femtosecond scale time resolution for nanophotonics applications. This ... |
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| Real Time RF Propagation Simulation Support for AFSOR |
24 JUN 2004 |
73 pages |
| Authors:
Stephen A. Fast; C. C. Marston; REMCOM INC STATE COLLEGE PA
|
| Recent research activities have been conducted to define the propagation and attenuation of communications signals through the atmosphere. These have, to a certain extent, allowed for the consideration of numerous factors, including multipath, ducting, diffraction, terrain, and weather phenomena. The Air Force Flight Test Center and the Navy Air Combat Environment, Test and Engineering Facility both require the capability to accurately represent the "real world" atmospheric propagation of communications signals ... |
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| A TE11 Ka-Band Gyro-TWT Amplifier with High-Average Power Compatible Distributed Loss |
JUN 2004 |
10 pages |
| Authors:
Dean E. Pershing; Khanh T. Nguyen; Jeffrey P. Calame; Bruce G. Danly; Baruch Levush; NAVAL RESEARCH LAB WASHINGTON DC VACUUM ELECTRONICS BRANCH
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| Current amplifier research at the Naval Research Laboratory Vacuum Electronics Branch emphasizes techniques to extend the bandwidth and average power capability of gyro devices for millimeter wave radar applications. This paper will discuss the implementation of a wideband high-gain gyro-traveling wave tube amplifier design, with a measured peak output power of 78 kW, gain ^60 dB, and a 3-dB bandwidth of 4.2 GHz (12%) at 52 kW in Ka-band. The ... |
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| Sub-100nm, Maskless Deep-UV Zone-Plate Array Lithography |
07 MAY 2004 |
154 pages |
| Authors:
Harry I. Smith; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
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| Semiconductor lithography is at a crossroads. With mask set costs in excess of $1M, long mask-turn-around times, and tools that are characterized by their inflexibility and skyrocketing costs (in excess of $20M), there is need for a new paradigm in lithography. Zone-Plate-Array Lithography (ZPAL) bypasses some of the most pressing problems of current lithography equipment by offering a maskless lithography tool that is scalable, flexible and low cost. It is ... |
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| RCS Scatterer Extraction Using Apriori Target Information |
23 MAR 2004 |
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| Authors:
J. T. Mayhan; MASSACHUSETTS INST OF TECH LEXINGTON LINCOLN LAB
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| Target component feature extraction is an area of considerable importance to the Ballistic Missile Defense (BMD) community. In particular, extracting essential target features from measurement data on targets of interest leads to potential target identification. The extracted component features correspond to a numerical characterization of the Geometrical Theory of Diffraction (GTD) diffraction coefficient and can also be used to develop a computationally efficient, measurement based RCS signature prediction model. A ... |
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