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  • Volume 55, Issue 05
  • Volume 55, Issue 05

    FIGURE 1. The outgoing laser beam of an FMCW lidar is chirped repeatedly in frequency (top), with each scan shorter than the time needed for laser light to make a round trip to the object (center). The continuous beam is scanned across the field of view, with a small fraction returned to the receiver that mixes light from the laser transmitter, as shown in the inset at bottom.
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    Lasers for Lidar: FMCW lidar: An alternative for self-driving cars

    May 31, 2019
    Frequency-modulated coherent lidar promises to collect more of the data computers need to drive cars—the challenge is to bring down costs and improve performance.
    Conard 720
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    Business Forum: Gender equity in photonics pays off

    May 1, 2019
    In the early 1990s, when I attended my first technical sessions at CLEO, I was not surprised that the audience was overwhelmingly male. That was a long time ago and, thankfully...
    FIGURE 1. A schematic depicts the MagAssemble pattern writing process, in which the write head rasters back and forth across the perpendicular magnetic recording medium within each track. By selectively changing the magnetic-field direction of each bit, the charge transition boundaries create a custom 2D template (a). When the template is introduced into a magnetic nanoparticle solution, nanoparticles self-assemble along the magnetic charge transitions (b).
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    Pattern-transfer nanomanufacturing for micro-optics and spectroscopy

    May 1, 2019
    Programmable self-assembly of nanoparticle patterns enables a low-cost platform for nanoscale to mesoscale structures such as life-science substrates, custom diffraction gratings...
    Microscope design without oculars is greatly simplified (a); Etaluma’s optics module is shown (b).
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    Disruptive fluorescence microscopy

    May 1, 2019
    Advances in microscope components—lighting, filters, and cameras—are creating a paradigm shift in system design, with far-reaching impact.
    FIGURE 1. A simplified schematic shows the main elements of a weathering testing chamber.
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    Novel sputtering technology improves optical coatings for solar simulation

    May 1, 2019
    A clever spin on sputtered coating technology provides a more accurate simulation of sunlight.

    More content from Volume 55, Issue 05

    (Courtesy of Hamamatsu)
    FIGURE 1. As seen in this schematic, a confocal laser scanning microscope includes two PMTs for light-sensing.
    Detectors & Imaging

    Photomultiplier tubes are at the forefront of low-light detection

    May 1, 2019
    Based on tried-and-true tube technology, PMTs still have, for many applications, low-light performance unmatched by other technologies.
    (Image credit: Takao Aoki/Waseda University)
    In the coupled-cavity QED system, cavities 1 and 2 of length L1 and L2 (with coupling rates v1 and v2 as well as atom-cavity coupling rates of g1 and g2, respectively) couple to a length of fiber Lf; measurements are made from left to right using a probe beam.
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    Quantum Computing: All-fiber QED system aims for deterministic rather than probabilistic quantum entanglement

    May 1, 2019
    An all-optical-fiber coupled-cavities quantum electrodynamics (QED) system demonstrates a reversible interaction between atoms and photons separated by 2 m of fiber—an important...
    (Image credit: NASA and Discovery Semiconductors)
    An ultrafast InGaAs dual-depletion region photodiode (a) with a radiation-hardened design and spanning 1060 to 1650 nm was incorporated into a fiber-coupled 16.8 GHz module (b) that survived 18 months on the ISS as part of the MISSE 7 mission launched on the Space Shuttle Atlantis and returning on the Space Shuttle Endeavor.
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    Photodetectors: Radiation-hardened InGaAs photodiodes survive rugged space-based qualification testing

    May 1, 2019
    Dual-depletion region InGaAs photodiodes have a radiation-hardened architecture that qualifies them for the rigors of lidar, communications, and referencing systems in space-based...
    Lasers & Sources

    LED-pumped actively Q-switched Nd:YLF laser has TEM00 beam quality

    May 1, 2019
    With LED pumping of only 14 W/cm2 peak power, an acousto-optically Q-switched Nd:YLF laser produces pulses with duration of 452 ns and energy of 10.6 μJ.
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    Optics

    Off-spindle-axis spiral ground molds produce sub-micron-accurate aspheric microlens arrays

    May 1, 2019
    Fabrication of aspheric microlens arrays through direct cutting or grinding methods can be expensive and limited to small batches; a new off-axis spindle grinding method forms...
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    Test & Measurement

    Light-activated microwave method improves semiconductor carrier-lifetime measurement

    May 1, 2019
    A circuit analog of time-resolved microwave reflectance using an RF-concentrating resonator amplifies the response to optical excitation of a small volume of optoelectronic material...
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    Fiber Optics

    Fiber-optic quantum-key distribution technique perfectly times photons’ arrival

    May 1, 2019
    Matching two QKD entangled photons’ wavelengths to the right parts of the fiber dispersion curve for two fiber routes allows both photons to arrive simultaneously.
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    Lasers & Sources

    Multiwavelength vat polymerization creates multimaterial 3D-printed components

    May 1, 2019
    By illuminating a mixture of polymers with different wavelengths of light in a pre-determined spatial and temporal pattern, standard vat polymerization can build a multimaterial...
    2105 Lfw Lpms Supp 9a
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    Not a bad penny

    May 1, 2019
    Editor in Chief John Lewis celebrates the life of Andrew Charles Wilson, his impact on machine vision and imaging, and introduces Laser Focus World’s May 2019 issue, which includes...