• Back Issues >
  • Laser Focus World >
  • Volume 51, Issue 06
  • Volume 51, Issue 06

    Content Dam Lfw Print Articles 2015 06 1506lfwnb4 Web
    Spectroscopy

    Portable spectrometer eases carbon black material characterization

    June 1, 2015
    A portable Raman spectrometer can clearly distinguish the defect band that characterizes the disorder parameters for carbon black.
    Content Dam Lfw Print Articles 2015 06 1506lfwnb5 Web
    Detectors & Imaging

    Photonic crystal nanocavity assists upconversion IR detection

    June 1, 2015
    A near-infrared upconversion photodetector has responsivity of 0.81 A/W for 1 W of coupled power.
    Content Dam Lfw Print Articles 2015 06 1506lfwnb3 Web
    Optics

    'Transmitarray' flat metamaterial lenses have focusing efficiency of 82%

    June 1, 2015
    Researchers have created a metamaterial flat lens that has a focusing efficiency of 82% for light at a 1550 nm wavelength.
    Content Dam Lfw Print Articles 2015 06 1506lfwnb2 Web
    Optics

    SEEOR liquid-crystal beam scanner outpaces diffractive alternatives

    June 1, 2015
    A liquid crystal waveguide approach scans a 30° × 5° field of view at a frame rate of less than 50 ms/frame.

    More content from Volume 51, Issue 06

    1506 Lfw Nb 1
    Lasers & Sources

    Near-IR VCSEL illuminator emits 108 kW of optical power

    June 1, 2015
    A VCSEL-based illuminator unveiled by Princeton Optronics emits 108 kW of optical power at a 1064 nm wavelength.
    (Image credit: Keysight Technologies)
    Absorption lines from an acetylene (12C2H2) gas cell are acquired at a 200 nm/s sweep speed (a) and compared to known values (b, according to NIST SRM 2517a); less than ± 1 pm deviation of the measured center wavelengths is possible using the 81606A tunable laser.
    Lasers & Sources

    Tunable Lasers: Tunable laser achieves subpicometer repeatability at full sweep speed

    June 1, 2015
    A newly developed tunable laser is capable of subpicometer tuning repeatability, even at full sweeping speeds up to 200 nm/s.
    (Courtesy of Coherent)
    Cross sections of 0.7-mm-thick Corning CT24 glass are taken with a Nomarski differential interference contrast microscope. The piece cut with a CO2 laser shows residual stress (a), while the cut produced with the CO laser is defect-free (b).
    Lasers & Sources

    Gas Lasers: Carbon monoxide laser aims at high-power applications

    June 1, 2015
    Coherent has unveiled a CO laser designed for materials-processing applications such as glass cutting, among other uses.
    Detection heads for LIF measurements are shown performing simultaneous inspection of the upper and lower surface of a coil material with a width of up to 2 m. The results for a scan of a complete coil surface (upside and downside) demonstrate the quantitative results of the lubrication measurement in a false color scale. Dry areas of more than 15 mm are detected and indicated in red.
    Spectroscopy

    Fluorescence Spectroscopy: Time-integrated LIF spectroscopy tackles lubricant surface analysis

    June 1, 2015
    Time-integrated laser-induced fluorescence, or LIF(t), spectroscopy is particularly beneficial for lubricant surface analysis.
    Frequency-doubled light from a superoscillatory nonlinear optical crystal has a narrower spectral linewidth than that from a conventional periodically poled crystal. Here, an experimental crystal has two channels: super-oscillatory, and conventional periodically poled (the control channel).
    Optics

    Nonlinear Optics: Nonlinear crystal does supernarrow-linewidth frequency conversion

    June 1, 2015
    Frequency conversion of laser light is a very common application for nonlinear optical crystals.
    (Image credit: CLARITY project)
    Mid-IR integrated components are fabricated on a chip (a) and telluride optical fibers operate at mid-IR wavelengths (b), thanks to advances by teams of researchers working on the CLARITY project.
    Research

    Mid-IR Technology: Project brings ‘CLARITY’ to mid-IR optoelectronic devices

    June 1, 2015
    Continuously increasing interest in silicon photonics has inspired investigation of CMOS-compatible technologies for the mid-IR.
    (Courtesy of FrinGOe)
    A working prototype of FrinGOe demonstrates the miniature spectrometer adapted to work on an Apple iPhone 5S (a). Although the prototype covers the iPhone camera even while not in use, next-generation versions will allow the spectrometer element to be slid aside when not in use, allowing the phone’s camera to be used conventionally. A spectral scan of a fluorescent lamp (b) across most of the visible spectrum shows characteristic peaks.
    Spectroscopy

    Spectroscopy: Miniature all-passive FTIR spectrometer fits on mobile phones

    June 1, 2015
    A scientific-grade, FTIR-based add-on spectrometer can be easily adapted for use with a mobile phone or a Raspberry Pi camera.
    Robert Alfano
    Software

    Business Forum: Diversity in photonics strengthens society

    June 1, 2015
    We spoke with Dr. Robert Alfano on his important role in advancing women and minorities in science and technology.
    Conard Mug 2011c
    Software

    The media and the mission at 50

    June 1, 2015
    Although these past 50 years of media change were unimaginable, we have continued our mission to cover a wide variety of subjects.
    1506 Lfw Mi
    Lasers & Sources

    Market Insights: U.S. military high-energy laser development hindered by ITAR regulations

    June 1, 2015
    The United States Senate Armed Services Committee requested comment from the OSA concerning the perceived lethargy in U.S. development of high-energy lasers with military applications...
    (Courtesy of Edmund Optics)
    Complex aspheric surface profiles can greatly reduce or eliminate many aberrations in spherical-lens optical systems.
    Optics

    Laser Optics: Selecting the right aspheres for laser applications

    June 1, 2015
    Manufacturing processes including CNC polishing, precision glass molding, or hybrid aspherizing are combined with inspection and testing techniques to integrate aspheres into ...
    FIGURE 1. An active vibration isolation setup for a sensitive system with mass m consists of a passive spring k, a damper d, a force generating element A, a sensor, and a control circuit-in this case, a velocity feedback (a). With active damping, the resonance of the undamped system can be reduced beyond the effect of passive damping as indicated in the transmissibility plot. The green area below 0 dB indicates the amount of isolation in comparison to a rigid connection (b).
    Positioning, Support & Accessories

    Vibration Control: Piezoelectric bimorph beams consolidate vibration control functions

    June 1, 2015
    The integration of multifunctional elements can offer reduced complexity and more compact, cost-effective vibration control designs.
    FIGURE 1. The Corning monolithic visNIR HSI sensor is 6 × 2.5 × 2.4 in. and weighs 0.45 kg (a); the laboratory monolithic HSI sensor can be configured for scanning and illumination (b) or as a portable sensor with built-in scanner (c).
    Detectors & Imaging

    Spectral Imaging: Compact, high-performance hyperspectral imaging systems

    June 1, 2015
    Hyperspectral imaging sensors enable deployment in demanding applications in platforms such as small unmanned aerial vehicles (UAVs).
    FIGURE 1. The absorption spectrum is shown for standard optical and low-absorption single-crystal diamond grades. Also shown are wavelengths available using a diamond Raman laser to shift the fundamental and two harmonics of a Nd:YAG laser.
    Optics

    Optical Materials: CVD diamond extends Raman laser capabilities

    June 1, 2015
    Single-crystal diamond enables improved Raman frequency shifting of high-power laser systems.