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    • Volume 55, Issue 06

    More content from Volume 55, Issue 06

    For a microcrystalline SiC thin-film thermal emitter in a cavity-coupled setup (a), a platinum heater ring (b) heats the suspended thermal emitter structure while minimizing conductive losses into the surrounding substrate. The suspended region stays hot while the temperature shifts to blue (cold) in the nonsuspended region of the substrate (c). (Image credit: Columbia University)
    A carefully designed optical cavity enhances the broadband thermal emission of the thin-film emitter, chosen for its unique coupling capability.
    June 1, 2019
    Plasma-ion-assisted deposition (PIAD) produces high-quality optical thin film layers; PIAD films have the desired properties of complete oxidation and high packing density distributed over a wide substrate area.
    The Multipole Resonance Probe (MRP) is a promising way to supervise optical coating processes using active plasma resonance spectroscopy.
    June 1, 2019
    FIGURE 1. Two basic connector concepts include a cylindrical connector (a) and a cone connector (b); mechanical reference areas are marked red and the impinging laser radiation is shown in green.
    New plug-and-play fiber connector provides switchable kilowatt output power.
    June 1, 2019
    FIGURE 1. Shown is the temporal dependence of various laser-induced damage mechanisms for pulsed lasers.
    The ISO 21254 LIDT specification itself is a broad guideline; further refinement helps to best correlate LIDT specifications to real performance.
    June 1, 2019
    A nonperiodic pinhole-based photon sieve widens the display angle of a lensless digital dynamic holographic display produced by a liquid-crystal-based spatial light modulator (SLM). At top, a dynamic holographic display without the nonperiodic photon sieve has a narrow viewing angle. At bottom, a holographic display with the nonperiodic photon sieve, which diffracts light at a high angle, has a larger viewing angle. The pinhole array in the sieve is made nonperiodic to avoid creating periodic arrays of diffraction artifacts. The researchers note that the holographic objects to be displayed need to appear within the shaded regions to prevent clipping.
    Spatial-light-modulator-based holographic displays’ narrow viewing angles are widened by diffraction from pinholes.
    June 1, 2019
    FIGURE 1. Glass marked and engraved for lab-on-chip devices (a) and stainless steel marked with permanent, high-contrast, high-resolution graphics (b) were both accomplished using an Origami ultrashort-pulsed laser. (Courtesy of Optek Systems)
    Advances in optical fibers and laser cavity engineering have dramatically improved the beam characteristics and efficiency of ultrafast lasers used for manufacturing medical devices...
    June 1, 2019
    For nonlinear high-peak-power beam propagation in which the beam size is smaller than the inner scale size of the turbulence or the transverse coherence length, the beam remains...
    June 1, 2019
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    An ultrastable erbium-doped fiber laser oscillator delivers femtosecond-accurate timing signals over dispersion-compensated fiber to enable global time-based coordinate reference...
    June 1, 2019
    FIGURE 1. Field of view (FOV) values can be compared for different VR headset displays; some other devices (not shown) include Google Daydream (100° FOV), Oculus Go (101°), HTC Vive Pro (110°), Samsung Odyssey (110°), Dell Visor (110°), and Lenovo Explorer (110°).
    Methods to measure augmented and virtual reality display quality must simulate the size, position, and field of view of the human eye to test the true visual experience of the...
    June 1, 2019
    A car engine piston off the production line of a large auto manufacturer is shown; the piston has been treated with a femtosecond laser for enhanced engine performance.
    Chirped-pulse amplification produces very energetic, very short ultrafast laser pulses; its use is benefiting numerous industries.
    June 1, 2019
    FIGURE 1. Shown is an example of diffuse reflection, where the diffuse reflected intensity I is a function of the incident light direction L and the surface normal n; albedo is the fraction of the incident sunlight reflected by the surface.
    By combining images obtained with varying directional illumination and analyzing the reflections, photometric stereo is an effective computational imaging technique to enhance...
    June 1, 2019
    FIGURE 1. Sandia National Laboratories’ Ihab El-Kady (right) and Charles Reinke developed software based on group theory to automate design for optical metamaterials.
    Mirage software aims to reduce an often months-long trial-and-error design process for complex metamaterials to only hours—with a more predictable and functional end-user result...
    June 1, 2019
    The new broadband multilayer dielectric (MLD) grating reaches >98.5% spectrally integrated diffraction efficiency for a bandwidth consistent with 30 fs short pulses; this performance is much better than for gold-coated dielectric ridge (GDCR) gratings. (Image credit: LLNL)
    Researchers have fabricated 1480 lines/mm gratings with an efficiency exceeding 97% over a 56 nm bandwidth and with a center wavelength of 810 nm.
    June 1, 2019
    A fluorescence-based system leverages CRISPR technology to enable quick detection of Ebola virus in small blood samples; the CRISPR reagent is introduced into the detection reservoir of the programmable, automated microfluidic device via lifting-gate micropumps.
    A rapid, point-of-care, fluorescence-based microfluidics screening device aims to decrease Ebola’s spread, and enable infected individuals to get treatment earlier.
    June 1, 2019
    FIGURE 1. Coupling of a light source into an optical fiber can be less efficient, as with an incandescent lamp, or more efficient, as with a bright spot on a Ce:YAG crystal.
    A new type of light source is needed for the small-diameter fiber-based illumination systems that are enabling leading-edge biomedical applications.
    June 1, 2019
    FIGURE 1. A single frame of Blackmore FMCW lidar data is colorized by the point cloud’s velocity data. Blues and greens indicate motion towards the sensor, while reds and oranges indicate motion aware from the sensor. White points are globally static and pink indicates retroreflective material such as street signs.
    Coherent detection and frequency-modulation techniques support interference-free measurement of range and velocity with minimal optical power.
    June 1, 2019
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    Editor in chief John Lewis celebrates recaps LASER World of PHOTONICS China, previews LASER World of PHOTONICS Munich, and introduces Laser Focus World’s June 2019 issue, which...
    June 1, 2019
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    MolecuLED (MLED) technology uses all-organic, nontoxic materials to shift and optimize the RGB spectra of existing white-light displays for better color gamut.
    June 1, 2019
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    Researchers have demonstrated a room-temperature optically pumped polariton nanolaser with potential applications in quantum information systems.
    June 1, 2019
    FIGURE 1. A conceptual image shows the HELIOS laser installed on a Navy destroyer, shooting down a drone. (Courtesy of Lockheed Martin)
    The Pentagon will soon roll out 50 kW-class solid-state lasers to see how well they can function on the battlefield—bigger lasers are on the drawing boards.
    June 1, 2019
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    Thanks to nonlinear optics plus quantum interference, images can be recorded with one wavelength that were taken with a different wavelength—opening up a vast range of new imaging...
    June 1, 2019