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    • Volume 44, Issue 12

    More content from Volume 44, Issue 12

    (Courtesy of Lawrence Livermore National Laboratory)
    The Laser Inertial-Confinement Fusion-Fission Energy (LIFE) approach will be much more compact than The National Ignition Facility (NIF) laser source. A successful LIFE engine could efficiently consume dangerous stockpiles of spent nuclear fuel, natural and depleted uranium, and weapons-grade plutonium, and produce carbon-free energy into the 21st century and beyond.
    The goal of the U.S. National Ignition Facility at Lawrence Livermore National Laboratory, due for completion in March 2009, the Laser MegaJoule , and the European High-Power ...
    Dec. 1, 2008
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    In addition to their starring role in negative-refractive-index materials and cloaking devices, metamaterials may play a new part in detectors of biological and chemical agents...
    Dec. 1, 2008
    FIGURE 1. The combination of a quadruple bandpass filter with a CMYG color CCD modifies the sensitivity of the color pixels. Each pixel has a different level of sensitivity to each of the four narrow spectral bands.
    A new and highly potent technique allows concurrent capture of application-defined spectral bands using standard color CCD cameras.
    Dec. 1, 2008
    (Courtesy of IMRA America)
    FIGURE 1. Scalable femtosecond lasers used at high scan rates perform well for cutting wafers, but results vary depending on scan speed. A SEM image of a wafer cut at 4 m/s scan speed (left) shows cleaner singulation than at 80 mm/s scan speed (right).
    Wafers singulated by a high-repetition-rate femtosecond fiber laser at high scan speeds show significantly higher breakage strength than those processed by a nanosecond laser....
    Dec. 1, 2008
    (Courtesy of E. F. Schubert, www.lightemittingdiodes.org)
    FIGURE 1. The three binary compounds are shown in this plot of bandgap energy and wavelength versus lattice spacing at room temperature for the GaInAlN family of semiconductors.
    Aluminum gallium nitride can emit light at wavelengths close to 200 nm, but developers need another breakthrough in materials before they can push semiconductor diode lasers into...
    Dec. 1, 2008
    FIGURE 1. Adaptive optics placed in the sample arm of an ultra-high-resolution OCT instrument corrects ocular aberration in real time.
    Ultra-high-resolution OCT imaging that uses adaptive optics is improved with a new source and optics for clinical in vivo visibility of the human retina.
    Dec. 1, 2008
    (Courtesy of Prism Solar Technologies)
    FIGURE 1. Holographic film (left), when used in a planar concentrator, collects light in areas not populated with PV cells (above). A mono-facial module design uses 50% less silicon than a conventional panel (right).
    In a holographic planar concentrator, holographic film diffracts usable frequencies of sunlight, and guides that energy toward strips of solar cells, resulting in a solar module...
    Dec. 1, 2008
    FIGURE 1. The typical photon-detection efficiency for a DAPD design has a nearly flat spectral response between 300 and 700 nm. The dashed red line represents measured photon-detection efficiency (sensitivity). Oscillations in efficiency are caused by optical interference due to lack of an antireflective coating. The solid blue line is the approximation of the experimental curve, fit through measured peak points. The dashed yellow curve, based on simulations, corresponds to the more accurate elimination of optical losses and represents the spectral response of the photodetector with an ideal antireflection coating.
    A new type of photodetector overcomes the limitations of avalanche photodiode technology by offering amplitude and event detection, wide dynamic range, and flat spectral response...
    Dec. 1, 2008
    (Courtesy of Boston University)
    Two-dimensional (x-y) QOCT sections of an onion-skin sample were taken at different axial (z) depths.
    Quantum optical coherence tomography (OCT) has, for the first time, been shown to be a viable biological imaging technique, says M. Boshra Nasr, a postdoctoral researcher in the...
    Dec. 1, 2008
    (Courtesy of Tufts University)
    FIGURE 1. A paper in the BiOS Symposium at Photonics West shows how the biocompatible nature of silk allows seamless embedding of active optics in everyday objects. The readout is provided by the optical element, for example, as a color or image change; when something unwanted is present (such as E. coli bacteria), the color changes or the holographic images disappear.
    Considered by many to be the premier event of the photonics industry, Photonics West 2009 gears up for another banner year.
    Dec. 1, 2008
    Scientists at Clemson University (Clemson, SC) have figured out how to fabricate a silicon (Si)-core, glass-clad optical fiber using a conventional fiber-draw process.
    Dec. 1, 2008
    The insertion loss for each of three optical fibers in a 3 × 3 visible-light multiplexer and white-light synthesizer is about 5.5 dB across a 100 nm test range.
    The synthesis of uniform white light from separate red, blue, and green LEDs gets more difficult as the area to be illuminated gets smaller and more akin to the size of the LEDs...
    Dec. 1, 2008
    (Courtesy of University of St. Andrews)
    An optical Airy beam (shown in white, illuminating from below a sample) exerts an optical gradient force on dielectric particles in suspension. In a “snowblowing” effect, the outer lobes of the Airy beam sweep a homogeneous mixture of particles toward the main spot in the beam (left), or toward the lower-left region of the sample area. If the beam is rotated by 180º (right), the particles are then swept toward the upper-right region of the sample area.
    Named after the famous British astronomer Sir George Airy, the Airy beam does not diffract or spread and can actually bend or curve as it propagates; in 2007, Airy light beams...
    Dec. 1, 2008
    (Courtesy of the University of Arizona)
    FIGURE 1. The LSST mirror has been cast and is ready for grinding and polishing. The outer 5- to 8.4-m-diameter portion will serve as the primary mirror; the inner 5-m-diameter portion will be ground to a steeper curvature and will become the telescope’s tertiary mirror.
    It was a year in which metamaterials began to take shape as optics, 80-attosecond pulses probed intra-atom electronic properties, optical interconnects benefited the digital revolution...
    Dec. 1, 2008
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    A family of 888 nm laser modules from QPC includes the Ultra-50, with output from 35 to 50 W, the Ultra-100, with output from 85 to 100 W, and the Ultra-5000, with output from...
    Dec. 1, 2008
    (Courtesy of the IBM Thomas J. Watson Research Center)
    An elastic scattering image of a nanotube-FET is recorded without the PMMA and top gold mirror (inset) is shown the G-band Raman scattering intensity of the isolated nanotube (top). Electroluminescence spectra from the same single-walled nanotube device (bottom) with (dashed red) and without (solid gray) gold top cavity mirror under electrical excitation show that the spectral width is narrowed by a factor of approximately 10 when the microcavity is formed.
    Although emission from direct-bandgap, semiconducting, current-injected carbon nanotubes is weak, spectrally broad, diffuse, and nondirectional in nature, researchers at the IBM...
    Dec. 1, 2008
    (Courtesy of National Physical Laboratory, Crown Copyright 2008)
    A low-coherence interferometry technique uses the results from an OCT microscope to determine sample thickness at multiple angles of incidence; the thickness values are then fitted to an equation that can calculate the bulk refractive index–even for biological materials that scatter light throughout their entire depth and cannot be measured by other conventional techniques.
    Although critical-angle refractometry techniques are well-established for measuring the refractive index of homogeneous transparent materials with an uncertainty on the order ...
    Dec. 1, 2008
    (Courtesy of Barredo et al.)
    A quantum-stabilized atom mirror, despite its small valleys (dark spots) and ”islands“ (bright spots), has a surface smooth enough to reflect a beam of helium atoms (left). A helium diffraction spectrum corresponds to a surface with four monolayers of Pb deposited at 110 K (above).
    Ultrasmooth mirrors could enable a new kind of microscope: a scanning helium-atom microscope that could use helium (He) particles as nondestructive probes to image nanometer-scale...
    Dec. 1, 2008
    (Courtesy of Siebold et al.)
    After compression with a spherical lens, the beam profile of the far field pattern of the terawatt diode-pumped Yb:CaF2 laser measures 108 × 50.3 µm.
    Lasers at terawatt (1012 W) powers have potential for all kinds of interesting new physics, but the systems are bulky, inefficient, and plagued by the difficulty of managing the...
    Dec. 1, 2008
    New research results appear to enhance the optoelectronic properties of organic semiconductors known as conjugated organic oligomers and polymers, and may eventually extend their...
    Dec. 1, 2008
    (Courtesy of the University of California at Riverside)
    A scanning-electron micrograph (SEM) of the ZnO surface shows the tops of closely packed nanocolumns (top left); a cross-sectional SEM faintly shows some column walls (top right). A schematic shows the position of the quantum well within the lasing film (bottom).
    Zinc oxide (ZnO) is an alternative to gallium nitride (GaN) as a UV-emitting semiconductor, but it is more difficult to make into lasers.
    Dec. 1, 2008
    A cooperative site hosted by Florida State University, “Molecular Expressions,” contains a myriad of photos in its galleries and explores the world of optics and microscopy with...
    Dec. 1, 2008
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    Photonics industry expert Sarah Diggs has joined our community with her new blog about the technical skills needed by engineers, researchers, and technicians in photonics.
    Dec. 1, 2008
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    G-S PLASTIC OPTICS specializes in the custom manufacture of precision polymer optics for use in imaging, scanning, detection, and illumination applications worldwide.
    Dec. 1, 2008
    In this month’s Annual Technology Review article, Senior Editor John Wallace leads us on a fascinating tour of photonics developments that have taken place over the past year....
    Dec. 1, 2008
    According to Baker, we leave a trail of electronic breadcrumbs on our computers and myriad mainframe machines of the credit-card companies, our banks, our Internet suppliers, ...
    Dec. 1, 2008
    1304qa Chang New
    As the downturn in the economy continues to make headlines, how will it impact our industry?
    Dec. 1, 2008