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    • Volume 52, Issue 01

    More content from Volume 52, Issue 01

    (Courtesy of OSA)
    The attenuated-total-internal-reflection (ATIR) spectrum for surface-plasmon polariton excitation for a properly oriented prism assembly (containing a gold thin film on the hypotenuse) highlights how sensitive the reflectivity can be to the slightest change in angle for certain angles (left). The optical system in which the prism is placed (right) also contains a deformable mirror (DM; to create a desired wavefront), a Hartmann-Shack wavefront sensor (HS WFS) for comparison, and a CCD camera to capture wavefront-slope images (insets at right).
    Wavefront sensors are at the heart of most adaptive optics (AO), which are used widely in systems ranging from astronomical telescopes, optical coherence tomography (OCT), and...
    Feb. 1, 2016
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    Because of its high refractive index of about 1.77, the sapphire-based aplanatic numerical-aperture-increasing lens (aNAIL) can produce a higher resolution than ordinary optics...
    Feb. 1, 2016
    FIGURE 2. A cascade of five beam expanders with M=21 and a design wavelength of 532 nm is used at a 600 nm wavelength (top). The wavefront, divergence, P-V, and RMS of the wavefronts after passing through the given number of beam expanders are compared (bottom).
    Single-element beam expanders containing an aspheric surface can be used in cascade to create different magnifications; an added lens adjusts for wavelength-change effects.
    Feb. 1, 2016
    (Courtesy of Nufern)
    FIGURE 1. A near-infrared pulsed laser signal is sent down an optical fiber, creating Rayleigh, Brillouin, and Raman backscattering—all of which are used for different types of distributed sensing, as seen in this spectral schematic. Brillouin and Raman scattering occur via the Stokes and anti-Stokes processes.
    Optical fibers used for sensing can measure temperature, strain, pressure, sound, electrical current, and even the 3D shape of the fiber itself.
    Feb. 1, 2016
    FIGURE 1. Precise control over peak power, marking speed, and number of pulses allows for color laser annealing (printing) on stainless steel with immense detail. Examples show a number of obtainable colors (a) and the high printed quality of a complex pattern (b).
    A compact, stable nanosecond-pulse DPSS marking laser with all-in-one thermal packaging is intended for widespread use by everyday users.
    Feb. 1, 2016
    FIGURE 1. Masked point-source LED during production, with and without reticle.
    Applications requiring extremely well-defined illumination patterns may benefit from LEDs modified to control the shape and size of the light aperture.
    Feb. 1, 2016
    FIGURE 1. Conceptual mapping from a point source to a freeform surface (P) to a set of target points (yn). The surface normals (Pn) are set to send the incident rays to their corresponding target points. The surface is then created using a B-spline surface interpolation [2].
    Newly developed tools integrated with commercial illumination software quickly create freeform reflective and refractive surfaces.
    Feb. 1, 2016
    FIGURE 1. A typical spectroscopy system consists of a light source, optical fiber, spectrograph, and a CCD detector.
    Accurate, repeatable wavelength and intensity information is possible for a spectrometer using an LED source and nonlinear optimization by taking into account variations in system...
    Feb. 1, 2016
    (Courtesy of ITRI)
    When combined with a PCOLED plasmon-coupled nanostructure layer, a green phosphorescent OLED layer (a) produces blue light (b). Combined with a red OLED (or alternatively with a red-shifting nanostructure), the result is a white-light OLED (c). These light emitters can have different hues such as warm (2039 K) or cool white (6000 K) (d). The technology is already being used to produce passive-matrix OLED displays (e).
    The thin-film nature of white organic light-emitting diode (OLED) lighting elements allows them to be made into large-area, glare-free lamps and luminaires shaped unlike any other...
    Feb. 1, 2016
    (Courtesy of UCLA)
    A terahertz quantum-cascade (QC) vertical-external-cavity surface-emitting laser (VECSEL) consists of an active metasurface reflector and output coupler (a); the metasurface is patterned with a metal-metal waveguide subcavity array (b). A scanning-electron microscope (SEM) image shows the metasurface reflector and its 1.5 × 1.5 mm2 active area (c).
    Since the demonstration of continuous-wave (CW) quantum-cascade (QC)-based terahertz lasers in the early 2000s, researchers have continued to increase power-output levels to the...
    Feb. 1, 2016
    FIGURE 1. A blue LED can excite phosphors emitting at longer wavelengths and contribute blue light to make white light (a), and red, green, and blue lights can be combined to generate white light-adjusting relative outputs of the three colors can tune the wavelength (b). Other variations are possible.
    Making the most of LED light sources requires refinements in color measurement and standards, and an understanding of how the color sensitivity of the eye varies in the range ...
    Feb. 1, 2016
    (Courtesy of Florida State University)
    In the layered manganese oxide material called birnessite (a), substitution of different cations at three potential sites (b) allows tailored bandgap tuning such that the material can trap light and be used in a photosynthesis-type process to generate energy.
    Splitting water (H2O) through an oxidation process into hydrogen fuel and oxygen or converting carbon dioxide (CO2) into a fuel such as methanol requires a large amount of energy...
    Feb. 1, 2016
    Dr. Y.S. Liu
    Dr. Y.S. Liu, formerly Vice Chancellor of the University System of Taiwan and Macronix Professor at the Institute of Photonics of National Tsing Hua University (NTHU), is Distinguished...
    Feb. 1, 2016
    Alan Willner
    Alan Willner is president of The Optical Society, steering committee chairman of the National Photonics Initiative, and Steven and Kathryn Sample Chair in Engineering at the Ming...
    Feb. 1, 2016
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    Most economic forecasters agree that the global economy is slowing. However, the attractive ROI and energy efficiency of today's laser technologies just may keep laser sales ahead...
    Feb. 1, 2016
    (Courtesy of Hans Bjelkhagen)
    An OptoClone of a Faberge Imperial Easter Egg, the 1897 Coronation Easter Egg, appears to viewers as if it were the object itself.
    Done correctly, a high-quality photographic-emulsion-based hologram can present a stunning 3D image that closely replicates the appearance of an actual object.
    Feb. 1, 2016
    (Image credit: NIST/Barnes)
    Scattered light from lines in a grid-like array at different angular positions and polarizations have varying planar profiles at different focal depths (a) and can be used to reconstruct the 3D line shapes when paired with optical and computational techniques. The pattern of wiggly lines is used to compute estimated uncertainties in the experimental data (b) and the colors correspond to the magnitude of the variance for specific data points.
    As the size of semiconductor wafer features continues to shrink to low-double-digit nanometer values, inspection equipment is needed to ensure zero defects at reasonable process...
    Feb. 1, 2016
    Conard Holton2
    Global financial markets have continued their tumultuous ways, so it's reassuring that photonics in general, and especially lasers, have followed steadier paths for growth and...
    Feb. 1, 2016
    FIGURE 1. Annual solar PV capacity installed each year has seen strong growth in recent years, with forecasts exceeding 60 GW during 2016.
    Historically, the relationship between the solar photovoltaic (PV) industry and laser-based equipment suppliers has been in start-stop mode.
    Feb. 1, 2016
    Barbaragoode2
    Attendees to the Biomedical Optics Symposium (BiOS), which will again comprise the major portion of SPIE Photonics West, will get to learn how new photonics advances improve surgical...
    Feb. 1, 2016
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    Mauna Kea Technologies (Paris, France) has received FDA clearance for use of its Cellvizio confocal laser endomicroscopy platform in surgery.
    Feb. 1, 2016
    Subdiffraction perforations in an array function as regularly spaced fluorescent point emitters. Widefield epi-illumination (green) passes through the glass coverslip into a nanoscale opening etched into a layer of aluminum. An aqueous solution of fluorescent dyes fills the nanohole from the top, and the spatially restricted light emitted from dyes diffusing within the hole (orange) is detected from below.
    Tracking how molecules move, form shapes, and interact within neurons and other cells offers a powerful view of biological processes that impact health.
    Feb. 1, 2016
    (Courtesy of Molex)
    FIGURE 1. A new high-transmission hollow waveguide design intended for use with carbon dioxide (CO2) surgical lasers consists of a glass tube coated on its inner surface with silver and silver iodide (AgI) films, and on its outside with a protective cladding and jacket. When coupled to a CO2 laser, the fiber serves as a flexible light-delivery tool for surgeons.
    A hollow silica-based optical fiber coated on its inside surface simultaneously transmits CO2 laser light and a visible aiming beam for surgery.
    Feb. 1, 2016
    (Courtesy of eVision Optics)
    Electrical connections to electrodes in a liquid crystal enable eyeglass lenses to be reprogrammed for different prescriptions in real time.
    The National Space Biomedical Research Institute (NSBRI) has awarded the makers two optics/photonics-based biomedical devices with grants.
    Feb. 1, 2016
    FIGURE 1. Simoa achieves single-molecule detection by confining fluorescent product to an extremely small volume. Beads, coated in antibodies designed to capture proteins, are loaded into arrays of microwells in the presence of protein-labeling enzyme substrate (a). Each femtoliter-sized well is sized to hold no more than one bead (b). The wells are then sealed with oil (c). If a target analyte has been captured (that is, an immunocomplex has formed), the substrate will fluoresce (d). This high local concentration of fluorescent product molecules can then be imaged (e).
    Single-molecule technologies are now allowing measurement of proteins at subfemtomolar concentrations. The advance has enabled the development of assays to detect various cancers...
    Feb. 1, 2016
    (Image credit: SPIE)
    FIGURE 1. As in this image from SPIE Photonics West 2015, the 2016 event is expected to draw more than 20,000 attendees destined to gain new insights and seize new opportunities in the world of photonics.
    SPIE Photonics West is expected to draw more than 20,000 attendees to listen to 4800 technical presentations, visit 1250 exhibitors, and take advantage of numerous professional...
    Jan. 4, 2016