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  • Volume 47, Issue 11

    • Volume 47, Issue 11

    (Courtesy of Northwestern University)
    FIGURE. Testing for the deep-UV FPA shows the spatial map of the peak detection wavelength (top). The deep-UV focal-plane array (FPA) easily images a US dime (bottom) illuminated by a 254 nm germicidal UV lamp.
    Detectors & Imaging

    FOCAL-PLANE ARRAYS: Northwestern develops solar-blind, deep-UV FPA

    Gail Overton
    Nov. 11, 2011
    In the solar-blind region, the ozone layer in our atmosphere absorbs nearly 100% of the Sun’s energy for wavelengths shorter than 285 nm.
    Test & Measurement

    Fixed 0.85/1.5 and tunable 0.8–2.8 THz sources ideal for spectroscopy

    Gail Overton
    Nov. 1, 2011
    Microtech Instruments launched its terahertz parametric oscillator TPO-850, a 0.85 THz source that propagates over long distances.
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    Optics

    PC fiber filled with nanomagnetic fluid becomes a magnetic-field sensor

    John Wallace
    Nov. 1, 2011
    A photonic-crystal (PC) fiber-based magnetic-field sensor created by scientists at the Defence Institute of Advanced Technology and Fergusson College combines the flexibility ...
    Optics

    Silk spins out biologically based light-emitting OLETs

    Gail Overton
    Nov. 1, 2011
    Biodegradable silk proteins have been demonstrated to function as edible optical components including diffraction gratings and lenses, as well as silk-based biosensors.
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    Research

    Co-doped luminescent glass creates white light from UV LEDs

    John Wallace
    Nov. 1, 2011
    The vast majority of white-light LEDs in use today consist of the combination of a blue-emitting gallium nitride (GaN)-based diode source and a yellow YAG:cerium phosphor.

    More content from Volume 47, Issue 11

    (Courtesy of R. Ostendorf, Fraunhofer Institute)
    FIGURE 1. Laser diodes having broad-area gain regions and tapered gain regions both emit similar power. However, the tapered structure produces more uniform gain within the laser and more uniform output across the emitting facet, as shown on the left.
    Lasers & Sources

    PHOTONIC FRONTIERS: HIGH-POWER LASER DIODES: Bringing high brightness to high-power laser diodes

    Jeff Hecht
    Nov. 1, 2011
    High-power laser diodes excel in generating light efficiently, but they have fallen short in producing the high-quality beams needed for many applications. New laser designs, ...
    (Courtesy of Politecnico di Milano all images [3])
    FIGURE 1. The vertical cross-section (a) of a typical thin double epitaxial single-photon avalanche diode (SPAD) is contrasted with the cross-section of the active region of a thin SPAD (b) with a qualitative electric field profile for the multiplying space-charge region.
    Detectors & Imaging

    SINGLE-PHOTON DETECTORS: Planar architecture optimizes Si single-photon-counting detectors

    Nov. 1, 2011
    A new planar structure for silicon single-photon-counting detectors leads to the doubling of detector efficiency while maintaining picosecond timing resolution, low dark counts...
    FIGURE 1. Comparison of the data logs collected simultaneously by the Swept Sensor (blue trace) and the MIRAN SapphIRe (green trace). The gray shaded areas represent three background measurements during which the Swept Sensor was not monitoring the air in the surgery room.
    Research

    TUNABLE SOURCES: Quantum cascade lasers enter industrial applications

    Nov. 1, 2011
    Known as a mid-IR tool for research or military applications, tunable quantum cascade laser-based systems are now available for spectroscopy applications that include detecting...
    1304qa Chang New
    Executive Forum

    Business Forum: Getting the best business perspective

    Milton Chang
    Nov. 1, 2011
    You must switch your mindset from that of a researcher writing a grant proposal to that of a practical businessperson when you write a business plan.
    (Courtesy of LightMachinery)
    The reflectivity of a 100-µm-thick solid fused-silica etalon varies widely with angle, making it suitable as the partially transmitting component of the UBS (top). A UBS mounted in a standard mirror mount splits a beam (path of beam is sketched in for clarity).
    Optics

    LAB OPTICS: Beamsplitter has widely adjustable splitting ratio

    John Wallace
    Nov. 1, 2011
    In response to frequent requests for custom beamsplitters, the research and development staff at LightMachinery has developed an adjustable beamsplitter that the company calls...
    (Courtesy of University of Electronic Science & Technology of China for all images)
    FIGURE 1. A schematic shows a micromachining system that uses a 157 nm excimer laser.
    Fiber Optics

    FIBERS FOR SENSING: Fiber-optic Fabry-Perot sensors take the strain under high temperature

    Nov. 1, 2011
    Directly engraved on silicon or sapphire fibers using a 157 nm laser micromachining system, highly accurate micro fiber-optic Fabry-Perot interferometric (MFFPI) sensors are well...
    A bulk heterojunction (BHJ) organic tricolor detector includes, from bottom to top, a blue Bragg reflector, an ITO-coated glass substrate, the BHJ, a layer of water and electrolyte, and a platinum-coated, ITO- or FPO-coated glass cover.
    Detectors & Imaging

    ORGANIC PHOTODETECTORS: Single-layer polymer pixel senses three colors

    John Wallace
    Nov. 1, 2011
    A single layer of polymer in an optical sensor developed by researchers at the Jawaharlal Nehru Centre for Advanced Scientific Research can sense multiple colors without using...
    Optics

    II-VI-based Bragg mirror looks good for future blue VCSELs

    John Wallace
    Nov. 1, 2011
    Distributed-Bragg-reflector gratings fabricated in II-VI semiconductor materials by researchers at the University of Bremen and the Romanian Academy could be the basis for future...
    (Courtesy of the University of Connecticut and ODIS)
    A GaAs/AlGaAs quantum-well resonator forms the basis of a III-V semiconductor optical modulator with a rectangular waveguide structure (top). The POET modulator device is shown in cross section (bottom; shown at dashed line through top figure).
    Research

    INTEGRATED PHOTONICS: GaAs modulator is first POET alternative to Si photonics

    Gail Overton
    Nov. 1, 2011
    Scientists and engineers from OPEL Technologies affiliate ODIS Inc. and its research and development center located at the University of Connecticut have developed a high-speed...
    FIGURE 1. a) A scanning-electron micrograph shows a probe tip. b) An optical pump/probe setup is used for terahertz time-domain measurements. c) A scale model of the probes shows the configuration and orientation used for the measurements.
    Optics

    TERAHERTZ IMAGING: Terahertz reflectometry images faults in silicon chips

    Nov. 1, 2011
    Terahertz imaging microprobes boost the accuracy of reflectometry-based fault location in silicon chips into the sub-micron range.
    (Courtesy of JILA)
    In a tabletop soft x-ray coherent diffractive imaging system, a femtosecond laser pulse is focused into a gas-filled waveguide to produce coherent 13 nm high-harmonic beams. The resultant diffraction pattern produced by light diffracted from the sample is captured on a CCD camera and reconstructed into an image (inset) using an iterative phase-retrieval algorithm.
    Research

    NANOSCALE IMAGING: Nanometer-resolution imager uses a 13 nm tabletop source

    Gail Overton
    Nov. 1, 2011
    Scientists and engineers are constantly working to improve nanometer-regime imaging technologies.
    Conard Holton2
    Research

    Exploring the spectrum

    Conard Holton
    Nov. 1, 2011
    The deep-ultraviolet wavelengths have been challenging detector makers for many years.
    Optics

    Crossed femtosecond filaments form plasma grating in air

    John Wallace
    Nov. 1, 2011
    A group at East China Normal University has shown self-channeling filaments created by femtosecond-laser pulses can interact in air to form a 2D plasma grating that diffracts ...
    FIGURE 1. Evaporative deposition produces porous coatings that can absorb moisture, while IAD reduces this problem and IBS completely eliminates it.
    Detectors & Imaging

    THIN-FILM COATINGS: Military laser technologies challenge optical-coating manufacturers

    Nov. 1, 2011
    Optical coatings for military applications often need to simultaneously satisfy many extreme requirements; coating manufacturers have responded with an array of design and fabrication...
    FIGURE 1. Before (top) and after (bottom) images illustrate how the Alex TriVantage—which emits 532, 755, and 1064 nm laser light—removes tattoos (left; courtesy of Dr. G. Goldberg) and treats pigment lesions (right; courtesy of S. Kilmer).
    Lasers & Sources

    PHOTONICS APPLIED: AESTHETIC PHOTONICS: Looking good with lasers

    Gail Overton
    Nov. 1, 2011
    Aesthetic photonics for wrinkle and hair removal, eye and cosmetic surgery, and laser liposuction, just to name a few, are part of a growing aesthetic medical device business ...