bluuebunny/crossref_metadata_2025_split huggingface dataset:
Optical Illusions
Authors: Hurlbert Anya 
Published: August 2007

AbstractVisual illusions are tools with which vision scientists probe the visual system. Illusions are misperceptions of reality; some arise from limitations of the eye in image formation, and are rightly calledopticalillusions; some from neural adaptation, others from fundamental mechanisms of image reconstruction and interpretation that must operate even in the presence of inadequate, misleading, conflicting, or no sensory information. This chapter samples illusions of these different types in the perception of different visual attributes: lightness, color, size, shape, motion, and depth.
Optical Metrology
Authors: deGroot Peter 
Published: August 2007

Abstract
The article reviews the optical measurement of shape, texture, geometric dimensions, and position of objects, with applications ranging from stage metrology to optical comparators. An emphasis is placed on mechanical and geometric metrology, as opposed to remote sensing. The underlying technologies rely therefore on interferometry, triangulation, and time of flight to determine distances and lengths, as well as those object features accessible to length measurement, including, for example, form and roughness.
Optical Techniques for the Analysis and Characterization of Chemicals and Materials
Authors: Andrews David L. 
Published: August 2007

Abstract
Optical methods are widely used by industry, academia, medicine, and the military for the analysis and characterization of chemicals and materials. Prominent amongst these techniques are measurements based on infrared spectroscopy, ultraviolet and visible spectroscopy, molecular fluorescence, and Raman scattering. Microscopy and imaging procedures are also leading features in the analysis of heterogeneous samples, and a variety of laser‐based diagnostic methods are applied for specialized applications. In this account, the fundamental and technical issues for optical characterization are first examined, and then each of the major techniques is discussed in detail. Examples range from flame analysis to the determination of protein structures, surface optical nonlinearity, and chiral characterization.
Optical Techniques for Mechanical Measurement
Authors: Wykes Catherine 
Published: August 2007

AbstractIt is possible to measure a range of mechanical properties using light. These include presence, position, displacement, velocity, acceleration, surface form, and surface finish. This article summarizes the various methods and outlines the factors that limit their measurement performance. Representative values for commercially available systems are quoted where they are available and examples of applications are cited. The techniques discussed are presence detection, surface finish, optical triangulation, laser radar, interferometry, laser Doppler vibrometry and laser Doppler anemometry, electronic speckle pattern interferometry, holographic interferometry, moiré methods, and vision systems.
Optoelectronics
Authors: Kasap Safa O. 
Published: August 2007

Abstract
It is useful to view today's optoelectronics in terms of various functional categories, most important of which are the generation of light, modulation of light, transmission of light and its connection between devices, amplification of light, switching of light, isolation of light, filtering of light, wavelength multiplexing and demultiplexing of light, and detection of light. The corresponding devices that implement these functions are light emitters (or light sources), modulators, waveguides and connectors, optical amplifiers, optical switches, optical isolators, optical filters, multiplexers and demultiplexers, and detectors. This introductory article reviews the principles of operation and characteristics of a number of selected devices to provide a general introduction to the field of optoelectronics with an emphasis on optical communications—a major area of application.
Photography, Physics and Technology
Authors: Schuster Norbert 
Published: August 2007

Abstract
After 150 years of development in photography, everybody can take good snapshots to remember by. The physical relationships involved in obtaining a sharp and well‐illuminated picture are presented here. Fine mechanical, optical, and electronic elements all work together in a modern photographic camera. The three mostly commonly used types of cameras, the viewfinder type, the Single Lens Reflex type, and the professional bellows camera, are explained in detail. All three types are used with classical film as well as in digital still cameras.
Polarization Optics, Polarimeters and Polarization Spectrometers
Authors: Hermann Gerd 
Published: August 2007

AbstractPolarimeters, employing polarization optics, are well known as highly precise and accurate instruments for determining optically active substances. Even simple manual polarimeters offer high accuracies compared to other analytical methods. Also, more sophisticated devices with half‐shadow adjustment and with quartz‐wedge compensation were already constructed in early times of polarimetry.High improvement of polarimeters has been obtained with modern automated and semiautomated instruments. Until now, polarimetry has been the main analytical standard method for determining sucrose in the sugar and beverage industries and is an important tool for controlling production processes of optically active substances. For obtaining high precision and accuracy, the brightness and monochromaticity of the light source is important.While polarimetry is based on intrinsic optical activity, polarization spectroscopy also measures anisotropies that may be induced into isotropic atomic or molecular species by DC electric or magnetic fields or also by interaction with radiation. Doppler‐free methods of nonlinear polarization spectroscopy yield high spectral resolution and result in the suppression of interferences by extremely close‐lying lines. Polarization spectroscopy based on an applied DC magnetic field, which is also denoted as coherent forward scattering spectroscopy (CFS), allows simultaneous multielement determination in combination with continuum light sources and the measurement over an extremely wide dynamic range.
Polarized Light, Basic Concepts of
Authors: Huard Serge J. 
Published: August 2007

Abstract
Polarization of light is a consequence of the vectorial nature of electromagnetic waves. This concept must be taken into account in a large number of optical phenomena such as birefringence, modulation of light, and propagation in optical devices. A representation of the states of polarization will first be analyzed. The propagation of light in linear or circular anisotropic media is carried out in the context of the phase velocity of the eigenstates of propagation. The evolution of a state of polarization traveling through a complex optical device will be finally presented.
Radiation Interaction with Molecules
Authors: Lombardi John R. 
Published: August 2007

Abstract

Various aspects of the interaction of electromagnetic radiation with matter are explored. The fundamental interaction involves the response of matter to electric and magnetic fields generated by the radiation. Any collection of charged particles will respond through its polarization
P
, which may be expanded in increasing powers of electric field
E
as
P
= χ
(1)
E
+ χ
(2)
E
2
+ χ
(3)
E
3
. The term χ
(1)
is called the
linear susceptibility
(or more commonly the
polarizability
α), and is the term responsible for the linear refractive index as well as for linear absorption. The first order susceptibility is shown to be responsible for normal one‐photon spectroscopy, and we examine microwave, infrared, and optical spectroscopy as tools to obtain information as to the rotational, vibrational, and molecular orbital nature of molecules. Rydberg states, vibronic interactions, and magnetic resonance spectroscopy are also considered. χ
(2)
is the second‐order polarizability, sometimes called the
hyperpolarizability
β. This is responsible for hyper‐Rayleigh scattering and second‐harmonic generation, as well as the hyper‐Raman effect. These are often termed
two‐photon effects
owing to the quadratic dependence on the electric field. Three‐photon effects are obtained from the third‐order polarizability χ
(3)
or γ. Stimulated Raman spectroscopy and four‐wave mixing are some of the most important consequences of this term. These involve coherent anti‐Stokes Raman scattering (CARS) as well as Raman‐induced Kerr‐effect spectroscopy (RIKES).
Remote Sensing
Authors: Zalewski Edward F. 
Published: August 2007

Abstract
Remote Sensing is defined for space‐borne and airborne imaging instruments that use electromagnetic radiation. The historical background for this field of study is presented. The methods of remote sensing are described along with the portions of the electromagnetic spectrum that are utilized. The role of the atmospheric transmission limits and the corrections necessary for optimum accuracy is described. The different types electromagnetic detectors are described along with the image collection systems in which they are used. Modern remote sensing is possible because of the improvement in the accuracy of the radiometric calibration and characterization of the sensors and these methods are briefly described. The objective of remote sensing is the quantitative interpretation of the images, specifically obtaining the data products. Several examples of the basis for some of the data products are presented. Some of the remote sensing systems presently in use are briefly described. The future of remote sensing is described in terms of some of the planned sensors systems and the challenges that must be met in order to understand the Earth and mankind's effect on its climate.
Spectrometers, Infrared
Authors: Kauppinen Jyrki K. , Hollberg Matti R. , Keens Axel 
Published: August 2007

Abstract
This paper is a review‐type article dealing with infrared (IR) spectrometers and their applications. The paper represents general aspects of IR spectrometry and general principles of IR spectrometers. Performance properties of IR spectrometers and especially detectors are defined and described. More detailed descriptions are given for prism, grating, Fourier transform (FT), and laser spectrometers. Because nowadays most of the IR spectra are recorded by FT‐IR spectrometers, the main attention of the paper is aimed at FT‐IR instruments. The advantages of FT spectrometers as compared with grating spectrometers are also demonstrated. The paper gives a large number of typical examples of applications of FT‐IR spectrometers in science and practical analysis.
Spectroscopy, Ultrafast
Authors: Dantus Marcos , Gross Peter 
Published: August 2007

AbstractSpectroscopy studies the interaction between light and matter. Ultrafast spectroscopy involves the study of this interaction using temporally short light pulses capable of probing directly the dynamics of the system rather than its energy levels. Rapid advances in laser technology over the past decades have resulted in the generation of pulses with femtosecond time duration (1fs = 10−15 s). These lasers are being used to interrogate solids, liquids, and gases to learn about the dynamics of matter (electrons, atoms, molecules) following laser excitation. The description given here explains how an ultrashort laser pulse excites a coherent superposition of energy levels, and how this excitation can be followed in time. To date, ultrafast spectroscopy has been used to measure processes in diverse fields, for example, to measure the time it takes to break or form a chemical bond; to measure the temporal response of molecules involved in photosynthesis, or vision; and to measure the flow of charge in semiconductors. Examples of these kinds of studies illustrate this presentation.
Underwater Optics
Authors: Dolin Lev S. , Levin Iosif M. 
Published: August 2007

Abstract
Four major subjects of the underwater optics are especially important, both for fundamental study of interaction between light and water and for various technical applications. These are (1) inherent optical properties (IOP) of natural waters; (2) propagation of natural and artificial light in the water; (3) optical methods for investigation of natural waters, and (4) underwater imaging. These four items form the main content of the paper and determine the titles of its four main sections.
Section 2 presents the definitions of IOP determining light absorption and scattering in water. Methods of measuring IOP are discussed, and data on spatial and spectral distributions of IOP in natural waters are given. Physical and empirical low‐parametric models considered in the section make it possible to determine the whole set of IOP distributions, based on few measurements. Section 3 deals with the underwater light fields. Methods for solving the radiative transfer equation are considered. The section presents data on the solar irradiance and angular radiance distributions near the sea surface and at the sea depth, as well as on the light field of artificial sources. Optical methods for investigation of natural waters are discussed in Sect. 4. This section is mainly concerned with the problem of remote sensing of phytoplankton, suspended and dissolved matters by measuring the ocean color, with the account of algorithms for atmospheric correction of satellite measurements. Finally, Sect. 5 is devoted to the problem of underwater imaging. The presented theory connects the image parameters, such as modulation transfer function, contrast, signal/noise ratio with the parameters of light sources, detectors, water, and target. Comparison of the sighting range and spatial resolution in water ensured by different underwater imaging systems is given.
Ultrashort‐pulse Phenomena
Authors: Powers Peter E. , Spence David E. , Tang Chung L. 
Published: August 2007

AbstractUltrashort‐pulse phenomena are generally processes that occur on the subpicosecond to femtosecond time scale. The availability of lasers that generate ultrashort optical pulses has made possible the study of effects and processes that occur on ultrashort time scales. These measurements have led to a more fundamental understanding of processes in fields ranging from chemical kinetics to semiconductor physics. The high peak powers attainable with ultrashort‐pulse lasers has also led to new applications such as soft X‐ray generation and multiphoton microscopy. In this article, we review the generation, characterization, and a few of the applications of ultrashort optical pulses. We briefly introduce these topics with the goal of presenting an overview of the fundamental ideas. An extensive list of references is provided for each topic to give a starting point for further research.
Wave Optics
Authors: Dallas William J. 
Published: August 2007

Abstract

Narrowly interpreted, the term
wave optics
encompasses propagation, diffraction, interference, and thin films. Under a broader interpretation, wave optics includes those areas of optics governed by the electromagnetic wave equation. We begin with a brief review of the wave equation, which is built on the foundation of Maxwell's equations. Next is a translation of the wave equation into the propagation relations of linear systems theory. An interesting and useful aspect of propagation is the existence of helical light; light that twists as it travels. Another aspect of optical waves is its propagation from curved surfaces. We move on to interference and then diffraction. The hologram serves as an important example of interference, while the computer‐generated hologram is an example of control over diffraction. Talbot, or Fourier self‐imaging, is a stunning example of the richness of propagation from diffractive optical elements. Finally, we discuss the subject of phase retrieval from irradiance distributions on multiple surfaces.
Zeeman and Stark Effects
Authors: Silverman Mark P. 
Published: August 2007

AbstractThe Zeeman and Stark effects are modifications of spectral lines (displacements, splittings, and polarization changes) induced respectively by magnetic and electric fields. Application of an external static field splits the energy levels of a degenerate multiplet of states. In the Zeeman effect, levels shift up or down in energy depending on the magnitude and sign of the magnetic quantum number; in the Stark effect the shift depends only on the magnitude of the magnetic quantum number. Resulting spectral line patterns depend on the relative size of the field‐induced level splittings compared to the separation between different multiplets. This article discusses the weak‐, strong‐, and ultrastrong‐field Zeeman effects (the latter case arising when the magnetic interaction is comparable to the binding energy), and the linear and quadratic (including “ac”) Stark effects. In highly excited atoms (Rydberg atoms), where the separation between distinct manifolds is small and the electric polarizability enormous, the full range of Zeeman and Stark effects can be induced by relatively low fields. These effects have been employed to probe atomic and molecular structure, to measure inaccessible (e.g., stellar and interstellar) fields, and to gauge the influence of stray external fields in high‐precision metrology.
Wet Adsorption of a Luminescent EuIII complex on Carbon Nanotubes Sidewalls
Authors: Accorsi G. , Armaroli N. , Parisini A. , Meneghetti M. , Marega R. , Prato M. , Bonifazi D. 
Published: August 2007

AbstractA EuIII complex, tris‐dibenzoylmethane mono‐1,10‐phenanthroline‐europium(III) [Eu(DBM)3(Phen)], can be easily adsorbed in situ via hydrophobic interactions to single‐walled carbon nanotube (SWNT) surfaces from a methanol solution. The EuIII‐containing material has been comprehensively characterized via thermogravimetric analysis (TGA), UV‐vis‐NIR absorption and luminescence spectroscopy, Raman spectroscopy, atomic force microscopy (AFM), high‐resolution transmission electron microscopy (HR‐TEM)), Z‐contrast scanning transmission electron microscopy (STEM) imaging, and energy dispersive X‐ray spectroscopy (EDS). The photophysical investigations revealed that the presence of a SWNT framework does not affect the lanthanide‐centered luminescence stemming from the characteristic electronic transitions within the 4f shell of the EuIII ions. Such straightforward synthetic route leads to the preparation of luminescent SWNTs without significantly affecting the electronic and structural properties of the carbon framework, opening new possibilities of designing new classes of CNTs for biomedical applications.
Studies of the Temperature and Frequency Dependent Impedance of an Electroceramic Functional Oxide NTC Thermistor
Authors: Schmidt R. , Brinkman A. W. 
Published: August 2007

AbstractThe charge transport mechanism and the macroscopic dielectric constant in polycrystalline device materials commonly exhibit several components such as electrode‐sample interface, grain boundary and bulk contributions. In order to gain precise understanding of the functionality of polycrystalline electroceramic device materials it is essential to deconvolute these contributions. The paradigm of functional NTC thermistor ceramics based on thick film spinel manganates has been studied by temperature dependent alternating current impedance spectroscopy. Three typical relaxation phenomena were detected, which all showed a separated temperature dependence of resistivity consistent with thermally activated charge transport. The dominating grain boundary and the interface contributions exhibited distinctively different capacitance allowing clear identification. The composite nature of the dielectric properties in polycrystalline functional ceramics was emphasized, and impedance spectroscopy was shown to be a powerful tool to account for and model such behavior.
Novel Heteroleptic CuI Complexes with Tunable Emission Color for Efficient Phosphorescent Light‐Emitting Diodes
Authors: Zhang Q. , Ding J. , Cheng Y. , Wang L. , Xie Z. , Jing X. , Wang F. 
Published: August 2007

AbstractA series of orange‐red to red phosphorescent heteroleptic CuI complexes (the first ligand: 2,2′‐biquinoline (bq), 4,4′‐diphenyl‐2,2′‐biquinoline (dpbq) or 3,3′‐methylen‐4,4′‐diphenyl‐2,2′‐biquinoline (mdpbq); the second ligand: triphenylphosphine or bis[2‐(diphenylphosphino)phenyl]ether (DPEphos)) have been synthesized and fully characterized. With highly rigid bulky biquinoline‐type ligands, complexes [Cu(mdpbq)(PPh3)2](BF4) and [Cu(mdpbq)(DPEphos)](BF4) emit efficiently in 20 wt % PMMA films with photoluminescence quantum yield of 0.56 and 0.43 and emission maximum of 606 nm and 617 nm, respectively. By doping these complexes in poly(vinyl carbazole) (PVK) or N‐(4‐(carbazol‐9‐yl)phenyl)‐3,6‐bis(carbazol‐9‐yl) carbazole (TCCz), phosphorescent organic light‐emitting diodes (OLEDs) were fabricated with various device structures. The complex [Cu(mdpbq)(DPEphos)](BF4) exhibits the best device performance. With the device structure of ITO/PEDOT/TCCz:[Cu(mdpbq)(DPEphos)](BF4) (15 wt %)/TPBI/LiF/Al (III), a current efficiency up to 6.4 cd A–1 with the Commission Internationale de L'Eclairage (CIE) coordinates of (0.61, 0.39) has been realized. To our best knowledge, this is the first report of efficient mononuclear CuI complexes with red emission.
Highly Stretchable and Conductive Polymer Material Made from Poly(3,4‐ethylenedioxythiophene) and Polyurethane Elastomers
Authors: Hansen T. S. , West K. , Hassager O. , Larsen N. B. 
Published: August 2007

AbstractA highly elastic and stretchable conductive polymer material resulted from blending the conductive polymer poly(3,4‐ethylenedioxythiophene):p‐tosylate and an aliphatic polyurethane elastomer. The blend inherited advantageous properties from its constituents, namely high conductivity of 120 S cm–1 from its conductive polymer component, and elastomeric mechanical properties resembling those of the polyurethane, including good adhesion to various substrates. Stretching of the blend material by up to 50 % resulted in increased conductivity, while subsequent relaxation to the unstretched state caused a decrease of conductivity compared to the pristine blend. These initial changes in conductivity were reproducible on further cycling between 50 % stretching and the unstretched state for at least 10 cycles. Stretching beyond 50 % resulted in decreasing conductivity of the blend but with substantial conductivity remaining even when stretched by 200 %. Optical, mechanical, and thermal properties of the blend, as well as high resolution electron microscopy of bulk cross‐sections, suggest that the system is a single phase and not two separate phases. Ageing experiments indicate that the material retains substantial conductivity for at least a few years at room temperature.
Electroosmosis with step changes in zeta potential in microchannels
Authors: Horiuchi Keisuke , Dutta Prashanta , Ivory Cornelius F. 
Published: August 2007

AbstractThis article presents an analytical solution for two‐dimensional fluid flow in a rectangular microchannel in the vicinity of a step change in the zeta (ζ) potential. The stream function is determined from the creeping flow approximation to the Navier‐Stokes equations assuming a fixed volumetric axial flow, a constant electric field, and thin symmetric double layers. The resulting biharmonic equation is solved using a double‐sided Laplace transformation, which is then inverted by Heaviside expansion. The resulting series solution provides closed‐form expressions for the velocity and pressure fields that help explain how the recirculating flows generated by an abrupt change in the surface potential may contribute both locally and globally to the hydrodynamic dispersion in straight microchannels. © 2007 American Institute of Chemical Engineers AIChE J, 2007