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  • Volume 51, Issue 01

    • Volume 51, Issue 01

    University of Alberta
    FIGURE 1. Singular Fabry-Perot (FP) resonance of evanescent waves can be achieved by setting the FP plates in relative motion. Plate 1 is stationary while plate 2 is moving at a constant velocity ν along the x direction. The reflection coefficients and the distance for the moving case can lead to a perfect balance of both phase and amplitude, which cannot occur for stationary plates.
    Jan. 16, 2015
    Fabry-Perot resonator elements that move relative to one another can lead to a perfect phase and amplitude balance, causing an ideal resonance condition despite material absorption...
    FIGURE 1. To evaluate a 785 nm Raman longpass edge filter for integration into a spectroscopy setup, the optical engineer faces three measurement challenges: confirm transmission of the passband, resolve and verify that steepness of the nearly vertical edge is OD6 @ 785 nm.
    Amber Czajkowski
    Jan. 16, 2015
    Measuring the new generation of steep bandpass filters with bandwidths less than 1 nm tests the resolution capabilities of instrumentation; more credible measurements in these...
    (Courtesy Christian Eggeling and Alf Honigman)
    FIGURE 1. STED microscopy overlaps a donut-shaped beam (for spatially selective photobleaching) with a Gaussian beam for fluorescence excitation. As the STED beam intensity is increased, it smoothly constricts the non-bleached area of the sample beyond the diffraction limit.
    Marco Arrigoni
    Jan. 16, 2015
    Fluorescence detection techniques for applications such as cytometry, microscopy, and sequencing continue to advance with support from evolving laser sources such as optically...
    (Polished axicon courtesy of Oz Optics; tapered axicon courtesy of AFL)
    FIGURE 1. A polished axicon (center) and tapered axicon (right) are shown, along with their corresponding ellipticities and beam shapes.
    Mike Harju
    Jan. 16, 2015
    Fiber lensing techniques, end cap technology, tapers, multicore fiber fan-outs, fiber combiners, mode field adapters, and overcladding all benefit from versatile new optical fiber...
    FIGURE 1. Examples of Rayleigh, Brillouin, and Raman scattering peaks relative to the wavelength of the input light signal.
    George Oulundsen
    Jan. 16, 2015
    Distributed temperature sensing (DTS) is the most common use of optical fiber-based sensors in oil recovery; the fibers are highly specialized and must withstand the high-temperature...

    More content from Volume 51, Issue 01

    FIGURE 1. Transmittance characteristics for a blocking filter (a) and a near-quarter-wave design solution obtained with a sensitivity-directed refinement (SDR) algorithm.
    Jan. 16, 2015
    New coating-design algorithms automatically produce designs suitable for real-life monitoring techniques and deposition processes, while retaining the coating's excellent spectral...
    Adapted from Hamamatsu Light Source, http://www.hamamatsu.com/resources/pdf/etd/LIGHT_SOURCE_TLSZ0001E01.pdf, Apr. 2014
    FIGURE 1. Stability of light output for various traditional UV light sources.
    Hari Venugopalan
    Jan. 16, 2015
    The traditional light sources used in UV spectroscopy can, for some uses, be replaced by LEDs, greatly reducing both capital and operating costs.
    (Courtesy of DILAS)
    FIGURE 1. The output beam of a 200 W laser-diode array made by DALSA and used to enhance MRI imaging is hexagonal with a beam size of ~63 mm.
    John Wallace
    Jan. 16, 2015
    With their high-power density, high efficiency, and long life, laser-diode arrays are the essential light source for materials processing, laser pumping, and other applications...
    FIGURE 1. The December 1974 cover of Laser Focus World featured the new technology of adaptive optics, which had a mirror with an array of 21 piezoelectric transducers that shaped its flexible surface.
    Jeff Hecht
    Jan. 16, 2015
    Half a century ago, optics were polished glass lenses with spherical shapes. Now we also have molded plastic and glass aspheres and a variety of infrared and UV materials. Tomorrow...
    Content Dam Lfw Print Articles 2015 01 1501lfw01f 1
    Gail Overton
    Jan. 16, 2015
    International initiatives like IYL 2015, NPI, Horizon 2020, the BRAIN, and IP-IMI can only help reinforce what our industry already knows: Lasers play a significant role in our...
    Conard Holton2
    Conard Holton
    Jan. 15, 2015
    The UN designation of 2015 as the International Year of Light and Light-based Technologies provides an excellent framework for highlighting the role and value of light in the ...
    Single-layer silicon films with different thicknesses deposited on an aluminum layer surface.
    Gail Overton
    Jan. 9, 2015
    Using two of the earth’s most abundant and inexpensive materials—silicon and aluminum—wavelength-selective perfect absorption optical color filters have been developed by researchers...
    Courtesy McGill University
    InGaN-based nanowire LEDs emit different colors depending on nanowire properties. A three-color LED pixel (top center); single-color LEDs emit (counterclockwise from left) red, yellow, green, and blue-green.
    John Wallace
    Jan. 9, 2015
    Indium gallium nitride (InGaN)-based LEDs have revolutionized the lighting and other industries, leading to high-power white-light LEDs, among other achievements.
    Courtesy of INAF
    The METIS coronagraph uses two main ultraviolet (UV)-enhanced coated mirrors (M1 and M2), a UV detector, an inverted external occulter (IEO), a sun disk light rejection mirror (M0), and an internal occulter (IO); VL = visible light.
    Gail Overton
    Jan. 8, 2015
    How is it possible to calibrate the ultraviolet (UV) channel of an imaging solar coronagraph as it flies through space? Just look to the stars.
    Content Dam Lfw Print Articles 2015 01 Wn Sic
    Jan. 8, 2015
    A laser-power meter (LPM) that uses a volume absorbing, single-crystal, silicon carbide (SiC) bolometer and detects wavelengths from 190 nm to 200 μm has been developed at Firebird...
    Professor Xi-Cheng Zhang
    Milton Chang
    Jan. 7, 2015
    I interviewed Professor Xi-Cheng Zhang, director of the Institute of Optics at the University of Rochester because it is a leading optical center that has made a major impact ...
    Content Dam Lfw Print Articles 2015 01 1501lfwnbf3web
    Jan. 7, 2015
    By using transition metal oxides and high-index amorphous chalcogenide glasses, a team of researchers has developed a substrate-blind platform that can tolerate deposition on ...
    1501lfwnbf4web
    Jan. 6, 2015
    A single nitrogen-vacancy defect center in a diamond can, when its optical properties and spin properties are queried by laser readout (for example, measuring the resulting polarization...
    (Courtesy SPIE)
    Core photonics suppliers worldwide. Less than 10% of companies employ ~77% of the workforce.
    Linda Smith
    Jan. 6, 2015
    According to research from SPIE, there are about 2750 companies worldwide supplying photonics components and materials, and they employ 700,000 people.