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    • Volume 47, Issue 1

    More content from Volume 47, Issue 1

    (Courtesy of PARC)
    A miniature interrogation module that fits in a TO header (top) uses a position-sensitive detector and a linear variable filter to resolve tiny wavelength changes. In a vibration experiment (bottom), wavelength changes as small as 50 fm are detected.
    Many optical sensors rely on the detection of small wavelength changes in response to changes in temperature, strain, adhesion of bioparticles, or change in the chemical environment...
    Jan. 1, 2011
    1101breaks Fig2
    A collaborative effort from researchers at the Harvard School of Public Health, Beth Israel Deaconess Medical Center, Massachusetts Institute of Technology, and the German Research...
    Jan. 1, 2011
    (All figures courtesy of Stefan A. Maier)
    FIGURE 1. Metallic nanoelements can be located relative to each other to accuracies as high as about 10 nm (a). Three stacked metallic bars form a nanostructure that absorbs but does not scatter light (b and c).
    Advances in plasmonic nanosystems enable manipulation of dark and bright modes, as well as concentration of light via transformation optics.
    Jan. 1, 2011
    Figure1
    Europe's ambitious program to develop short-pulse, high-intensity lasers begins work on three petawatt-class lasers this year. These lasers will point the way to plans for a 200...
    Jan. 1, 2011
    (Courtesy of the University of Illinois at Urbana-Champaign)
    Two examples of NIVI images show the technique's capability for finding tumors and their boundaries. The pixelation in the images comes from undersampling, rather than the optical resolution of the system. The blue color-coded regions have been classified as normal, the red as abnormal (tumor), and the pink as indeterminate. An algorithm automatically computes a black-line boundary based on the NIVI data.
    Diagnosing cancer in tissue biopsies has traditionally been done by experienced pathologists viewing a stained tissue sample under a microscope.
    Jan. 1, 2011
    FIGURE 1. Electron micrographs of the cross-sections of the as-drawn and cleaved glass-clad crystalline semiconductor core optical fibers—silicon (a), germanium (b), and indium antimonide (c)—show the fibers possess a clean interface between the semiconductor core and the glass cladding.
    Optical fiber with a semiconductor core has the potential to unify long, flexible, and robust fiber-based waveguides with the nonlinear, Raman, and infrared transparency of semiconducto...
    Jan. 1, 2011
    (Courtesy of the University of Kaiserslautern)
    A metamaterial terahertz-radiation-focusing GRIN lens has 60 μm wide unit cells consisting of a 200 nm thick copper film sandwiched between two slabs of benzocyclobutene, a dielectric.
    An optical metamaterial is made up of unit cells somewhat less than a wavelength in size.
    Jan. 1, 2011
    (Courtesy of Edward Buckley)
    Using a defined measurement geometry for laser safety (top), the IEC 60825-1 standard calls out the testing parameters for meeting particular laser-safety classifications (bottom).
    Picoprojectors, with typical output values below 50 lumens (50 lm), are based on a number of different architectures.
    Jan. 1, 2011
    42699
    Although laser industry sales recovered nicely across all sectors in 2010, the aftermath of the recession is still impairing visibility going forward.
    Jan. 1, 2011
    (Courtesy of Ohio State University)
    Images of a Mach 10 airflow around a triangular 'trip' object are taken at a 500 kHz frame rate using PLIF with nitric oxide as the fluorescent agent (top). The field of view is 5 × 5 cm, and the light sheet is 1.9 mm above the object's surface. The tests were done in NASA Langley's Mach 10 wind tunnel (bottom).
    Hypersonic air and space vehicles include the Space Shuttle and the US Air Force X-37B, which both re-enter the atmosphere at Mach 25 before slowing to subsonic speeds.
    Jan. 1, 2011
    (Courtesy of University of California–Merced)
    FIGURE 1. Optical energy spectra taken as a function of applied electric field reveal tunneling of a charge between two quantum dots (a). A slice (b) through the intense spectral line (red dash on left) is associated with the neutral quantum dot pair; two polarization components, πX and πY, can be distinguished [1,2].
    Pulse-tube and closed-cycle mechanical coolers can take optical systems down to temperatures where noise is low and performance is high.
    Jan. 1, 2011
    The story of the man and his arch-rivals who claim to have invented the "computer" has just been revived-for the fourth or fifth time.
    Jan. 1, 2011
    30573
    Last year the photonics marketplace exceeded expectations by recovering almost all of the ground it lost during the 2008/2009 recession.
    Jan. 1, 2011
    (Courtesy of University of Illinois at Urbana-Champaign for all images)
    FIGURE 1. The width of the point-spread functions for interferometric synthetic aperture microscopy (ISAM) and optical coherence tomography (OCT) are shown as a function of distance from focus.
    Optical coherence tomography (OCT) emerged in the early 1990s as the marriage of broadband interferometry and scanning-light microscopy.
    Jan. 1, 2011
    46484
    I read the news item in Laser Focus World [p. 18, November 2010] of the femtosecond news section, entitled "Laser pulse filaments produce Hawking radiation."
    Jan. 1, 2011
    1304qa Chang New
    Raising money is never easy for any business. The last three years have been especially challenging. Recently a number of successful IPOs and M&As have made the outlook more positive...
    Jan. 1, 2011
    FIGURE 1. In a spectrometer output, a ruler generated by precisely determined comb lines facilitates the exact measurement of frequencies in a wide spectral range.
    Besides applications in metrology (most notably, optical clocks), highly stable optical frequency combs are playing a role in ultraprecise spectroscopy for astronomy and in other...
    Jan. 1, 2011
    FIGURE 1. In comparison to a conventional SiPM, which has all electronics off-chip (top), a digital SiPM has cell electronics on-chip, including an ADC for each SiPM (bottom).
    All-digital silicon photomultipliers contain ADCs and other electronics on-chip and can be made using a conventional CMOS process.
    Jan. 1, 2011
    (Courtesy of ICFO and ICREA)
    A cascaded multicrystal second-harmonic generation scheme (a) yields an optical-to-optical conversion efficiency of up to 56% when converting a 1064 nm ytterbium fiber-laser output to 532 nm green light. The efficiency values are compared for single-crystal (SC), double-crystal (DC), and multicrystal (MC) configurations for a range of fundamental power levels up to 30 W (b).
    Due to the absence of suitable laser materials in the green wavelength range, second-harmonic generation (SHG) of near-infrared (IR) solid-state lasers near 1 μm has evolved as...
    Jan. 1, 2011