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  • Volume 44, Issue 4

    • Volume 44, Issue 4

    More content from Volume 44, Issue 4

    FIGURE 1. A top view (top left) and cross-sectional view (bottom left) of a conventional charge-coupled-device (CCD) image pixel is contrasted with a better-performing CCD (upper and lower right) pixel that uses vertical overflow drain.
    Developed for professional digital still cameras and high-definition TVs, leading-edge CCD technology now offers 12 12 m pixels with as much as 3k 4k-pixel resolution—ideal for...
    April 1, 2008
    Some 125 scientists, academicians, and representatives of government and industry from around the world met to discuss the future of biomedical optics at the first International Congress on Biophotonics in February in Sacramento, CA.
    Scientists, academicians, and representatives of government and industry spent several days discussing the future of biomedical optics at the first International Congress on Biophotonic...
    April 1, 2008
    (Courtesy of ORC)
    Line structures written along the +y and -y axis of an LiNbO3 sample are imaged using a quantitative phase microscopy system (left). Writing directions of the structures are shown by arrows and the lines were written by a laser beam directed along the z axis. The phase change across the dashed line is graphed (above).
    Researchers at the Optoelectronics Research Centre (ORC) at the University of Southampton (England) and the University of Joensuu (Finland) have presented what they claim is the...
    April 1, 2008
    (Courtesy of University of St. Andrews)
    Femtosecond pulses traveling within microstructured fiber are generating a supercontinuum (inset).
    Black holes may be the bane of science-fiction space heroes, but University of St. Andrews (Scotland) physicist Ulf Leonhardt’s descriptions of them can remind one of a movie ...
    April 1, 2008
    (Courtesy of JILA)
    A CO2-isotope trace from human breath exists in the form of many spectral lines. The graph at lower right is a “subtracted-absorption” image; the graph at top is the absorption spectrum recovered from the subtracted-absorption image.
    Ordinary human breath is rife with biomolecules that can reveal the presence or absence of certain diseases or metabolic processes.
    April 1, 2008
    (Courtesy Nanjing University)
    A Nd:YAG dual-wavelength oscillating laser with fundamental wavelengths at 1319 and 1064 nm is transformed into an RGB laser with oscillating emission of second-harmonic generated 660 nm (red) and 532 nm (green) light, as well as third-harmonic-generated 440 nm (blue) light from the 1319 nm fundamental wavelength. In effect, the quasi-white-light source is an oscillating RGB source.
    Most visual colors (including white) in projection displays and other lighting applications can be obtained by a weighted combination of red, green, and blue (RGB) light.
    April 1, 2008
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    More than a decade after its first demonstration, quantum-cascade laser technology is still progressing rapidly.
    April 1, 2008
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    Carrier-envelope-phase stabilization of amplified intense few-cycle pulses enables the generation of single attosecond pulses through high-order harmonic generation.
    April 1, 2008
    FIGURE 1. A galvanometer laser scanner uses a mirror pair sized to the input beam aperture over a range of rotation angles for the required scan field. Larger beam diameters can be focused to smaller spot sizes, but large mirrors can inhibit scan speed.
    Light weight, high stiffness, and good thermal conductivity make silicon carbide an ideal substrate for galvanometer mirrors in high-speed laser scanning systems.
    April 1, 2008
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    Many attempts have made to improve the resolving power of optical imaging systems since Ernst Abbe discovered at the end of the 19th century that the resolution of an imaging ...
    April 1, 2008
    (Courtesy of Intel)
    FIGURE 1. A silicon-on-insulator Raman laser with a “racetrack” cavity frequency down-converts a pump signal (to 1686 nm), which then acts as the pump of a second frequency down-conversion. The process can continue cascading, with each new order further into the infrared.
    The mid-infrared portion of the electromagnetic spectrum is generally a hard one to reach with laser sources, typically involving large and complex setups.
    April 1, 2008
    FIGURE 1. In the final configuration of Hubble after repairs are completed, COS will replace the old COSTAR corrective-optics module, WFC3 will replace WF/PC2, which was installed in 1993, and STIS and ATS will be repaired. Fine-guidance sensors, gyros, and batteries will also be replaced.
    NASA plans to install two new instruments and repair two others … the mission should make the Hubble Space Telescope better than new.
    April 1, 2008
    FIGURE 1. Despite its lower bandwidth and higher insertion loss, the large core diameter of plastic optical fiber combined with its inherent elasticity and ruggedness make it ideal for many applications not suited to glass fiber.
    Apart from low cost, the unique advantages of plastic optical fiber are ease of termination, large core diameter for easy fiber coupling, as well as ruggedness against mechanical...
    April 1, 2008
    FIGURE 1. A rectangular 1 × 1 mm2 hole cut in 400 µm plastic sheet (nylon) by 266 nm, 4 ps pulses exhibits no obvious traces of residual carbon that typically develops as black areas covering the cut. Note that adding 1064 nm picosecond pulses causes carbon to appear and the quality of the cut deteriorates. Such peculiarities arise from the undesirable heating of the plastic by the 1064 nm pulses.
    A technique that combines stretching and compression enables compact, inexpensive UV lasers for micromachining, spectroscopy, microscopy, and other applications.
    April 1, 2008
    FIGURE 1. A qubit of quantum information can be encoded in the polarization of a single photon (top) with horizontal polarization state (H) encoding the state |0〉, and vertical polarization (V) the state |1〉. A Poincaré sphere (bottom) can be used to plot any polarization, such as horizontal H, vertical V, diagonal D, antiagonal A, right-circular diagonal R, and left-circular L.
    Optical quantum computing was a dead-end street until the breakthrough of a scheme based on a massive optical nonlinearity induced by single-photon detection. Today it is a leading...
    April 1, 2008
    Measured and confirmed by the National Renewable Energy Laboratory (www.nrel.gov), solar cells developed by IMEC (Leuven, Belgium) reached a record conversion efficiency of 24...
    April 1, 2008
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    Scientists at Arizona State Unversity (ASU; Tempe, AZ) are using hyperspectral fluorescence imaging to identify and visualize discrete pigments in live bacteria cells.
    April 1, 2008
    At Pittcon 2008 (Mar. 2–7; New Orleans, LA), Rohit Bhargava from the University of Illinois (Urbana-Champaign) discussed his group’s work with Fourier-transform infrared ...
    April 1, 2008
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    Commercially available microspheres are being used in numerous applications—from creating white-light sources by coating red and green fluorescent microspheres on blue light...
    April 1, 2008
    Telecommunications components company Gemfire (Fremont, CA) completed a merger with Covega (Jessup, MD), a provider of indium phosphide and lithium niobate components and modules...
    April 1, 2008
    Panelists in the executive panel session at Photonics West 2008 are, from left, Ken Kaufmann of Hamamatsu, Randy Heyler of Newport, Robert Edmund of Edmund Optics, Mark Sobey of Coherent, Holger Schlueter of Trumpf, Stuart Schoenmann of CVI/Melles Griot, and Steve Turley of Bookham.
    Talk show host Larry King once said he could give a high-probability weather forecast for any day, any place: “partly cloudy, chance of rain.
    April 1, 2008
    Conard Holton2
    Machine vision guides agricultural topping and spraying.
    April 1, 2008
    Green lasers appear to have been very visible (sorry!) in both the trade publications and general large-circulation newspapers recently.
    April 1, 2008
    Next month, May, happens to be the 48th anniversary of the demonstration of the first working laser by Theodore Maiman at Hughes Research Laboratories in Malibu, CA.
    April 1, 2008
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    The article “3-D movie shows femtosecond pulse propagation,” presents a method of light-in-flight recording by holography and reports: “For the first time, three-dimensional (...
    April 1, 2008
    On the heels of its October 2007 $750,000 Phase II Small Business Innovation Research award from the National Institutes of Health for a joint effort with Northwestern University...
    April 1, 2008
    Navitar (Rochester, NY), a manufacturer and distributor of precision optics and optomechanical assemblies for the machine-vision and digital-projection industries, acquired Special...
    April 1, 2008
    Start-up company AdvanceSis (Coventry, England) announced a multimillion-dollar follow-on investment from its main shareholder, Seven Spires Investments, to develop applications...
    April 1, 2008
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    The Mantis oscillator for short-pulse, broadband, ultrafast applications has been optimized for a single operating point in terms of wavelength and bandwidth.
    April 1, 2008
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    Tunable absorption spectrometers using terahertz sources and detectors can detect chemical signatures from 0.1 to 1.1 THz with line widths and repeatability at the megahertz level...
    April 1, 2008
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    Gemstone appraisal has gone high-tech, thanks to a collaboration between researchers at New Mexico State University (NMSU; Las Cruces, NM) and ultrafast laser manufacturer Raydiance...
    April 1, 2008
    (Courtesy of University of Washington)
    Electronic circuits and micro light-emitting diodes (LEDs) have successfully been integrated into biocompatible contact lenses that could be used as virtual head-up displays, or as biosensors for monitoring glucose and blood oxygen levels, for example.
    Researchers at the University of Washington (Seattle, WA) have successfully embedded optoelectronic devices into a biocompatible contact lens.
    April 1, 2008
    Each year, student chapters and local sections of the Optical Society of America apply for activity grants to support grassroots education outreach projects.
    April 1, 2008
    (Courtesy of University of Michigan/Anatoly Maksimchuk)
    With the help of its new booster amplifier the Hercules Ti:sapphire laser at the University of Michigan’s Department of Electrical Engineering and Computer Science (EECS) produces 300 TW pulses - the highest ever achieved for a repetitively pulsed laser - with a repetition rate of 0.1 Hz.
    By adding a booster amplifier to their 50 TW Hercules laser, researchers at the University of Michigan (UM; Ann Arbor, MI) have pushed its peak power to 300 TW—the highest ever...
    April 1, 2008
    (Courtesy of Audi)
    A variable software-controlled rear LED turn signal developed by Volkswagen America allows drivers to “express their mood” by instantly changing the appearance of the signal.
    Several of the presentations at the Strategies in Light 2008 conference touched on the concept of “intelligent light”—the combination of software”—either internal (embedded) or...
    April 1, 2008
    (Courtesy of Naval Postgraduate School)
    A commercially available infrared microbolometer camera images radiation from a 2.8 THz quantum-cascade laser to reveal metal obscured within opaque plastic tape (top left). A single-frame image (top right) and a computational average of 50 images (bottom left) can be further refined by image-processing software to remove noise and produce a clearer image (bottom right).
    Short enough to provide submillimeter resolution capability, yet long enough to penetrate most nonmetallic materials, terahertz waves in the 0.3 to 10 THz spectral range are being...
    April 1, 2008
    (Courtesy of Antonio De Luca)
    In the experimental setup an Nd:YAG laser was used to pump a dye-doped sample freely suspended by means of a squared-comb PVC net (inset photo, left). The spatial distribution of the lasing peaks, which stochastically changes for each pump pulse, is shown in the inset (right bottom).
    A new demonstration of random lasing in a boundary-free system has shown new avenues to create random lasers in disordered systems.
    April 1, 2008