• Back Issues >
  • Laser Focus World >
  • Volume 44, Issue 12
  • Volume 44, Issue 12

    Th 302609
    Th 302609
    Th 302609
    Th 302609
    Th 302609
    Optics

    New Products

    Dec. 1, 2008
    A family of 888 nm laser modules from QPC includes the Ultra-50, with output from 35 to 50 W, the Ultra-100, with output from 85 to 100 W, and the Ultra-5000, with output from...
    Optics

    Photonic feats can fascinate

    Dec. 1, 2008
    In this month’s Annual Technology Review article, Senior Editor John Wallace leads us on a fascinating tour of photonics developments that have taken place over the past year....
    Th 302641
    Th 302641
    Th 302641
    Th 302641
    Th 302641
    Fiber Optics

    Manufacturers’ Product Showcase

    Dec. 1, 2008
    G-S PLASTIC OPTICS specializes in the custom manufacture of precision polymer optics for use in imaging, scanning, detection, and illumination applications worldwide.
    Th 302566
    Th 302566
    Th 302566
    Th 302566
    Th 302566
    Research

    BLOG: WORKING SMART IN PHOTONICS

    Dec. 1, 2008
    Photonics industry expert Sarah Diggs has joined our community with her new blog about the technical skills needed by engineers, researchers, and technicians in photonics.
    Research

    SCIENCE & TECHNOLOGY EDUCATION: Web site offers a wealth of science information

    Dec. 1, 2008
    A cooperative site hosted by Florida State University, “Molecular Expressions,” contains a myriad of photos in its galleries and explores the world of optics and microscopy with...

    More content from Volume 44, Issue 12

    (Courtesy of the University of California at Riverside)
    A scanning-electron micrograph (SEM) of the ZnO surface shows the tops of closely packed nanocolumns (top left); a cross-sectional SEM faintly shows some column walls (top right). A schematic shows the position of the quantum well within the lasing film (bottom).
    A scanning-electron micrograph (SEM) of the ZnO surface shows the tops of closely packed nanocolumns (top left); a cross-sectional SEM faintly shows some column walls (top right). A schematic shows the position of the quantum well within the lasing film (bottom).
    A scanning-electron micrograph (SEM) of the ZnO surface shows the tops of closely packed nanocolumns (top left); a cross-sectional SEM faintly shows some column walls (top right). A schematic shows the position of the quantum well within the lasing film (bottom).
    A scanning-electron micrograph (SEM) of the ZnO surface shows the tops of closely packed nanocolumns (top left); a cross-sectional SEM faintly shows some column walls (top right). A schematic shows the position of the quantum well within the lasing film (bottom).
    A scanning-electron micrograph (SEM) of the ZnO surface shows the tops of closely packed nanocolumns (top left); a cross-sectional SEM faintly shows some column walls (top right). A schematic shows the position of the quantum well within the lasing film (bottom).
    Research

    SEMICONDUCTOR LASERS: Ultraviolet ZnO laser diode has p-n junction

    Dec. 1, 2008
    Zinc oxide (ZnO) is an alternative to gallium nitride (GaN) as a UV-emitting semiconductor, but it is more difficult to make into lasers.
    Research

    OPTICAL MATERIALS: Photovoltaic-material sensitivity stretches from UV to near-IR

    New research results appear to enhance the optoelectronic properties of organic semiconductors known as conjugated organic oligomers and polymers, and may eventually extend their...
    (Courtesy of Siebold et al.)
    After compression with a spherical lens, the beam profile of the far field pattern of the terawatt diode-pumped Yb:CaF2 laser measures 108 × 50.3 µm.
    After compression with a spherical lens, the beam profile of the far field pattern of the terawatt diode-pumped Yb:CaF2 laser measures 108 × 50.3 µm.
    After compression with a spherical lens, the beam profile of the far field pattern of the terawatt diode-pumped Yb:CaF2 laser measures 108 × 50.3 µm.
    After compression with a spherical lens, the beam profile of the far field pattern of the terawatt diode-pumped Yb:CaF2 laser measures 108 × 50.3 µm.
    After compression with a spherical lens, the beam profile of the far field pattern of the terawatt diode-pumped Yb:CaF2 laser measures 108 × 50.3 µm.
    Research

    DIODE-PUMPED LASERS: Femtosecond pulses reach terawatt power via Yb:CaF2

    Lasers at terawatt (1012 W) powers have potential for all kinds of interesting new physics, but the systems are bulky, inefficient, and plagued by the difficulty of managing the...
    (Courtesy of Barredo et al.)
    A quantum-stabilized atom mirror, despite its small valleys (dark spots) and ”islands“ (bright spots), has a surface smooth enough to reflect a beam of helium atoms (left). A helium diffraction spectrum corresponds to a surface with four monolayers of Pb deposited at 110 K (above).
    A quantum-stabilized atom mirror, despite its small valleys (dark spots) and ”islands“ (bright spots), has a surface smooth enough to reflect a beam of helium atoms (left). A helium diffraction spectrum corresponds to a surface with four monolayers of Pb deposited at 110 K (above).
    A quantum-stabilized atom mirror, despite its small valleys (dark spots) and ”islands“ (bright spots), has a surface smooth enough to reflect a beam of helium atoms (left). A helium diffraction spectrum corresponds to a surface with four monolayers of Pb deposited at 110 K (above).
    A quantum-stabilized atom mirror, despite its small valleys (dark spots) and ”islands“ (bright spots), has a surface smooth enough to reflect a beam of helium atoms (left). A helium diffraction spectrum corresponds to a surface with four monolayers of Pb deposited at 110 K (above).
    A quantum-stabilized atom mirror, despite its small valleys (dark spots) and ”islands“ (bright spots), has a surface smooth enough to reflect a beam of helium atoms (left). A helium diffraction spectrum corresponds to a surface with four monolayers of Pb deposited at 110 K (above).
    Optics

    ATOM OPTICS: Smooth operator: a quantum-stabilized mirror is ‘smoothest surface ever’

    Ultrasmooth mirrors could enable a new kind of microscope: a scanning helium-atom microscope that could use helium (He) particles as nondestructive probes to image nanometer-scale...
    (Courtesy of National Physical Laboratory, Crown Copyright 2008)
    A low-coherence interferometry technique uses the results from an OCT microscope to determine sample thickness at multiple angles of incidence; the thickness values are then fitted to an equation that can calculate the bulk refractive index–even for biological materials that scatter light throughout their entire depth and cannot be measured by other conventional techniques.
    A low-coherence interferometry technique uses the results from an OCT microscope to determine sample thickness at multiple angles of incidence; the thickness values are then fitted to an equation that can calculate the bulk refractive index–even for biological materials that scatter light throughout their entire depth and cannot be measured by other conventional techniques.
    A low-coherence interferometry technique uses the results from an OCT microscope to determine sample thickness at multiple angles of incidence; the thickness values are then fitted to an equation that can calculate the bulk refractive index–even for biological materials that scatter light throughout their entire depth and cannot be measured by other conventional techniques.
    A low-coherence interferometry technique uses the results from an OCT microscope to determine sample thickness at multiple angles of incidence; the thickness values are then fitted to an equation that can calculate the bulk refractive index–even for biological materials that scatter light throughout their entire depth and cannot be measured by other conventional techniques.
    A low-coherence interferometry technique uses the results from an OCT microscope to determine sample thickness at multiple angles of incidence; the thickness values are then fitted to an equation that can calculate the bulk refractive index–even for biological materials that scatter light throughout their entire depth and cannot be measured by other conventional techniques.
    Optics

    OPTICAL MEASUREMENT: OCT technique measures bulk refractive index

    Dec. 1, 2008
    Although critical-angle refractometry techniques are well-established for measuring the refractive index of homogeneous transparent materials with an uncertainty on the order ...
    (Courtesy of the IBM Thomas J. Watson Research Center)
    An elastic scattering image of a nanotube-FET is recorded without the PMMA and top gold mirror (inset) is shown the G-band Raman scattering intensity of the isolated nanotube (top). Electroluminescence spectra from the same single-walled nanotube device (bottom) with (dashed red) and without (solid gray) gold top cavity mirror under electrical excitation show that the spectral width is narrowed by a factor of approximately 10 when the microcavity is formed.
    An elastic scattering image of a nanotube-FET is recorded without the PMMA and top gold mirror (inset) is shown the G-band Raman scattering intensity of the isolated nanotube (top). Electroluminescence spectra from the same single-walled nanotube device (bottom) with (dashed red) and without (solid gray) gold top cavity mirror under electrical excitation show that the spectral width is narrowed by a factor of approximately 10 when the microcavity is formed.
    An elastic scattering image of a nanotube-FET is recorded without the PMMA and top gold mirror (inset) is shown the G-band Raman scattering intensity of the isolated nanotube (top). Electroluminescence spectra from the same single-walled nanotube device (bottom) with (dashed red) and without (solid gray) gold top cavity mirror under electrical excitation show that the spectral width is narrowed by a factor of approximately 10 when the microcavity is formed.
    An elastic scattering image of a nanotube-FET is recorded without the PMMA and top gold mirror (inset) is shown the G-band Raman scattering intensity of the isolated nanotube (top). Electroluminescence spectra from the same single-walled nanotube device (bottom) with (dashed red) and without (solid gray) gold top cavity mirror under electrical excitation show that the spectral width is narrowed by a factor of approximately 10 when the microcavity is formed.
    An elastic scattering image of a nanotube-FET is recorded without the PMMA and top gold mirror (inset) is shown the G-band Raman scattering intensity of the isolated nanotube (top). Electroluminescence spectra from the same single-walled nanotube device (bottom) with (dashed red) and without (solid gray) gold top cavity mirror under electrical excitation show that the spectral width is narrowed by a factor of approximately 10 when the microcavity is formed.
    Optics

    NANOTECHNOLOGY: Current-driven nanotubes emit at IR wavelengths

    Dec. 1, 2008
    Although emission from direct-bandgap, semiconducting, current-injected carbon nanotubes is weak, spectrally broad, diffuse, and nondirectional in nature, researchers at the IBM...
    (Courtesy of Lawrence Livermore National Laboratory)
    The Laser Inertial-Confinement Fusion-Fission Energy (LIFE) approach will be much more compact than The National Ignition Facility (NIF) laser source. A successful LIFE engine could efficiently consume dangerous stockpiles of spent nuclear fuel, natural and depleted uranium, and weapons-grade plutonium, and produce carbon-free energy into the 21st century and beyond.
    The Laser Inertial-Confinement Fusion-Fission Energy (LIFE) approach will be much more compact than The National Ignition Facility (NIF) laser source. A successful LIFE engine could efficiently consume dangerous stockpiles of spent nuclear fuel, natural and depleted uranium, and weapons-grade plutonium, and produce carbon-free energy into the 21st century and beyond.
    The Laser Inertial-Confinement Fusion-Fission Energy (LIFE) approach will be much more compact than The National Ignition Facility (NIF) laser source. A successful LIFE engine could efficiently consume dangerous stockpiles of spent nuclear fuel, natural and depleted uranium, and weapons-grade plutonium, and produce carbon-free energy into the 21st century and beyond.
    The Laser Inertial-Confinement Fusion-Fission Energy (LIFE) approach will be much more compact than The National Ignition Facility (NIF) laser source. A successful LIFE engine could efficiently consume dangerous stockpiles of spent nuclear fuel, natural and depleted uranium, and weapons-grade plutonium, and produce carbon-free energy into the 21st century and beyond.
    The Laser Inertial-Confinement Fusion-Fission Energy (LIFE) approach will be much more compact than The National Ignition Facility (NIF) laser source. A successful LIFE engine could efficiently consume dangerous stockpiles of spent nuclear fuel, natural and depleted uranium, and weapons-grade plutonium, and produce carbon-free energy into the 21st century and beyond.
    Research

    LASER FUSION-FISSION: NIF is precursor to LIFE project

    Dec. 1, 2008
    The goal of the U.S. National Ignition Facility at Lawrence Livermore National Laboratory, due for completion in March 2009, the Laser MegaJoule , and the European High-Power ...
    (Courtesy of the University of Arizona)
    FIGURE 1. The LSST mirror has been cast and is ready for grinding and polishing. The outer 5- to 8.4-m-diameter portion will serve as the primary mirror; the inner 5-m-diameter portion will be ground to a steeper curvature and will become the telescope’s tertiary mirror.
    FIGURE 1. The LSST mirror has been cast and is ready for grinding and polishing. The outer 5- to 8.4-m-diameter portion will serve as the primary mirror; the inner 5-m-diameter portion will be ground to a steeper curvature and will become the telescope’s tertiary mirror.
    FIGURE 1. The LSST mirror has been cast and is ready for grinding and polishing. The outer 5- to 8.4-m-diameter portion will serve as the primary mirror; the inner 5-m-diameter portion will be ground to a steeper curvature and will become the telescope’s tertiary mirror.
    FIGURE 1. The LSST mirror has been cast and is ready for grinding and polishing. The outer 5- to 8.4-m-diameter portion will serve as the primary mirror; the inner 5-m-diameter portion will be ground to a steeper curvature and will become the telescope’s tertiary mirror.
    FIGURE 1. The LSST mirror has been cast and is ready for grinding and polishing. The outer 5- to 8.4-m-diameter portion will serve as the primary mirror; the inner 5-m-diameter portion will be ground to a steeper curvature and will become the telescope’s tertiary mirror.
    Research

    TECHNOLOGY REVIEW 2008: Photonic feats

    Dec. 1, 2008
    It was a year in which metamaterials began to take shape as optics, 80-attosecond pulses probed intra-atom electronic properties, optical interconnects benefited the digital revolution...
    (Courtesy of University of St. Andrews)
    An optical Airy beam (shown in white, illuminating from below a sample) exerts an optical gradient force on dielectric particles in suspension. In a “snowblowing” effect, the outer lobes of the Airy beam sweep a homogeneous mixture of particles toward the main spot in the beam (left), or toward the lower-left region of the sample area. If the beam is rotated by 180º (right), the particles are then swept toward the upper-right region of the sample area.
    An optical Airy beam (shown in white, illuminating from below a sample) exerts an optical gradient force on dielectric particles in suspension. In a “snowblowing” effect, the outer lobes of the Airy beam sweep a homogeneous mixture of particles toward the main spot in the beam (left), or toward the lower-left region of the sample area. If the beam is rotated by 180º (right), the particles are then swept toward the upper-right region of the sample area.
    An optical Airy beam (shown in white, illuminating from below a sample) exerts an optical gradient force on dielectric particles in suspension. In a “snowblowing” effect, the outer lobes of the Airy beam sweep a homogeneous mixture of particles toward the main spot in the beam (left), or toward the lower-left region of the sample area. If the beam is rotated by 180º (right), the particles are then swept toward the upper-right region of the sample area.
    An optical Airy beam (shown in white, illuminating from below a sample) exerts an optical gradient force on dielectric particles in suspension. In a “snowblowing” effect, the outer lobes of the Airy beam sweep a homogeneous mixture of particles toward the main spot in the beam (left), or toward the lower-left region of the sample area. If the beam is rotated by 180º (right), the particles are then swept toward the upper-right region of the sample area.
    An optical Airy beam (shown in white, illuminating from below a sample) exerts an optical gradient force on dielectric particles in suspension. In a “snowblowing” effect, the outer lobes of the Airy beam sweep a homogeneous mixture of particles toward the main spot in the beam (left), or toward the lower-left region of the sample area. If the beam is rotated by 180º (right), the particles are then swept toward the upper-right region of the sample area.
    Research

    OPTICAL MANIPULATION: Airy light ‘throws a curve ball’

    Dec. 1, 2008
    Named after the famous British astronomer Sir George Airy, the Airy beam does not diffract or spread and can actually bend or curve as it propagates; in 2007, Airy light beams...
    The insertion loss for each of three optical fibers in a 3 × 3 visible-light multiplexer and white-light synthesizer is about 5.5 dB across a 100 nm test range.
    The insertion loss for each of three optical fibers in a 3 × 3 visible-light multiplexer and white-light synthesizer is about 5.5 dB across a 100 nm test range.
    The insertion loss for each of three optical fibers in a 3 × 3 visible-light multiplexer and white-light synthesizer is about 5.5 dB across a 100 nm test range.
    The insertion loss for each of three optical fibers in a 3 × 3 visible-light multiplexer and white-light synthesizer is about 5.5 dB across a 100 nm test range.
    The insertion loss for each of three optical fibers in a 3 × 3 visible-light multiplexer and white-light synthesizer is about 5.5 dB across a 100 nm test range.
    Lasers & Sources

    VISIBLE ILLUMINATION: Mini white-light source has tunable color temperature

    Dec. 1, 2008
    The synthesis of uniform white light from separate red, blue, and green LEDs gets more difficult as the area to be illuminated gets smaller and more akin to the size of the LEDs...
    Research

    IR FIBERS: Silicon core is highly crystalline

    Dec. 1, 2008
    Scientists at Clemson University (Clemson, SC) have figured out how to fabricate a silicon (Si)-core, glass-clad optical fiber using a conventional fiber-draw process.
    (Courtesy of Tufts University)
    FIGURE 1. A paper in the BiOS Symposium at Photonics West shows how the biocompatible nature of silk allows seamless embedding of active optics in everyday objects. The readout is provided by the optical element, for example, as a color or image change; when something unwanted is present (such as E. coli bacteria), the color changes or the holographic images disappear.
    FIGURE 1. A paper in the BiOS Symposium at Photonics West shows how the biocompatible nature of silk allows seamless embedding of active optics in everyday objects. The readout is provided by the optical element, for example, as a color or image change; when something unwanted is present (such as E. coli bacteria), the color changes or the holographic images disappear.
    FIGURE 1. A paper in the BiOS Symposium at Photonics West shows how the biocompatible nature of silk allows seamless embedding of active optics in everyday objects. The readout is provided by the optical element, for example, as a color or image change; when something unwanted is present (such as E. coli bacteria), the color changes or the holographic images disappear.
    FIGURE 1. A paper in the BiOS Symposium at Photonics West shows how the biocompatible nature of silk allows seamless embedding of active optics in everyday objects. The readout is provided by the optical element, for example, as a color or image change; when something unwanted is present (such as E. coli bacteria), the color changes or the holographic images disappear.
    FIGURE 1. A paper in the BiOS Symposium at Photonics West shows how the biocompatible nature of silk allows seamless embedding of active optics in everyday objects. The readout is provided by the optical element, for example, as a color or image change; when something unwanted is present (such as E. coli bacteria), the color changes or the holographic images disappear.
    Research

    PHOTONICS WEST PREVIEW: Photonics West hailed as ‘essential photonics event’

    Dec. 1, 2008
    Considered by many to be the premier event of the photonics industry, Photonics West 2009 gears up for another banner year.
    (Courtesy of Boston University)
    Two-dimensional (x-y) QOCT sections of an onion-skin sample were taken at different axial (z) depths.
    Two-dimensional (x-y) QOCT sections of an onion-skin sample were taken at different axial (z) depths.
    Two-dimensional (x-y) QOCT sections of an onion-skin sample were taken at different axial (z) depths.
    Two-dimensional (x-y) QOCT sections of an onion-skin sample were taken at different axial (z) depths.
    Two-dimensional (x-y) QOCT sections of an onion-skin sample were taken at different axial (z) depths.
    Optics

    QUANTUM PHOTONICS: Nonclassical OCT images biological sample

    Dec. 1, 2008
    Quantum optical coherence tomography (OCT) has, for the first time, been shown to be a viable biological imaging technique, says M. Boshra Nasr, a postdoctoral researcher in the...
    FIGURE 1. The typical photon-detection efficiency for a DAPD design has a nearly flat spectral response between 300 and 700 nm. The dashed red line represents measured photon-detection efficiency (sensitivity). Oscillations in efficiency are caused by optical interference due to lack of an antireflective coating. The solid blue line is the approximation of the experimental curve, fit through measured peak points. The dashed yellow curve, based on simulations, corresponds to the more accurate elimination of optical losses and represents the spectral response of the photodetector with an ideal antireflection coating.
    FIGURE 1. The typical photon-detection efficiency for a DAPD design has a nearly flat spectral response between 300 and 700 nm. The dashed red line represents measured photon-detection efficiency (sensitivity). Oscillations in efficiency are caused by optical interference due to lack of an antireflective coating. The solid blue line is the approximation of the experimental curve, fit through measured peak points. The dashed yellow curve, based on simulations, corresponds to the more accurate elimination of optical losses and represents the spectral response of the photodetector with an ideal antireflection coating.
    FIGURE 1. The typical photon-detection efficiency for a DAPD design has a nearly flat spectral response between 300 and 700 nm. The dashed red line represents measured photon-detection efficiency (sensitivity). Oscillations in efficiency are caused by optical interference due to lack of an antireflective coating. The solid blue line is the approximation of the experimental curve, fit through measured peak points. The dashed yellow curve, based on simulations, corresponds to the more accurate elimination of optical losses and represents the spectral response of the photodetector with an ideal antireflection coating.
    FIGURE 1. The typical photon-detection efficiency for a DAPD design has a nearly flat spectral response between 300 and 700 nm. The dashed red line represents measured photon-detection efficiency (sensitivity). Oscillations in efficiency are caused by optical interference due to lack of an antireflective coating. The solid blue line is the approximation of the experimental curve, fit through measured peak points. The dashed yellow curve, based on simulations, corresponds to the more accurate elimination of optical losses and represents the spectral response of the photodetector with an ideal antireflection coating.
    FIGURE 1. The typical photon-detection efficiency for a DAPD design has a nearly flat spectral response between 300 and 700 nm. The dashed red line represents measured photon-detection efficiency (sensitivity). Oscillations in efficiency are caused by optical interference due to lack of an antireflective coating. The solid blue line is the approximation of the experimental curve, fit through measured peak points. The dashed yellow curve, based on simulations, corresponds to the more accurate elimination of optical losses and represents the spectral response of the photodetector with an ideal antireflection coating.
    Detectors & Imaging

    SINGLE-PHOTON DETECTORS: Discrete amplification dramatically improves single-photon detection

    Dec. 1, 2008
    A new type of photodetector overcomes the limitations of avalanche photodiode technology by offering amplitude and event detection, wide dynamic range, and flat spectral response...
    (Courtesy of Prism Solar Technologies)
    FIGURE 1. Holographic film (left), when used in a planar concentrator, collects light in areas not populated with PV cells (above). A mono-facial module design uses 50% less silicon than a conventional panel (right).
    FIGURE 1. Holographic film (left), when used in a planar concentrator, collects light in areas not populated with PV cells (above). A mono-facial module design uses 50% less silicon than a conventional panel (right).
    FIGURE 1. Holographic film (left), when used in a planar concentrator, collects light in areas not populated with PV cells (above). A mono-facial module design uses 50% less silicon than a conventional panel (right).
    FIGURE 1. Holographic film (left), when used in a planar concentrator, collects light in areas not populated with PV cells (above). A mono-facial module design uses 50% less silicon than a conventional panel (right).
    FIGURE 1. Holographic film (left), when used in a planar concentrator, collects light in areas not populated with PV cells (above). A mono-facial module design uses 50% less silicon than a conventional panel (right).
    Optics

    OPTICS FOR SOLAR ENERGY: Holographic planar concentrator increases solar-panel efficiency

    Dec. 1, 2008
    In a holographic planar concentrator, holographic film diffracts usable frequencies of sunlight, and guides that energy toward strips of solar cells, resulting in a solar module...