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    • Volume 46, Issue 6

    More content from Volume 46, Issue 6

    (Courtesy of Goodrich ISR Systems)
    In the SWIR image, there is rich contextual detail, but it is not easy to pick out the presence of a person in the distance since there is little contrast between the person and the wooded backdrop. In the corresponding LWIR thermal image, the person stands out in sharp contrast to the background. However, many very important scene-contextual clues, such as the presence of several cars (many of which have been sitting there for several hours) are lost. Even the layout of the parking lot is very difficult to discern from the thermal image component alone; it is nearly impossible to determine the potential presence of deep craters, bodies of water, or other obstacles in the LWIR image. Hinted SWIR combines both sensing modalities, clearly identifying the target.
    Image fusion is a process of combining video streams from multiple sensors into a single composite video stream in real time without losing contrast or resolution.
    June 1, 2010
    It has been my painful experience that compromises rarely work and, all too often, they inevitably produce "solutions" that are far worse than the original problems.
    June 1, 2010
    61691
    The eruption last April of the Eyjafjallajökul volcano in Iceland delivered a blunt reminder that, despite many advanced sensing technologies, our ability to monitor and analyze...
    June 1, 2010
    (Courtesy of Jean-Pierre Wolf/University of Geneva)
    An 800 nm femtosecond-laser beam causes water vapor to condense in a cloud chamber; the resulting droplets scatter light from a second laser emitting at 532 nm.
    Femtosecond lasers could have a new trick to add to the arsenal of effects they produce: They may be able to make it rain.
    June 1, 2010
    (Courtesy of the Institute for Infocomm Research)
    A proof-of-concept experiment demonstrates how a 448 × 448 optical crossconnect can be used to achieve error-free switching for 40 Gbit/s signals.
    Optical communication networks currently depend on electronic switching techniques to route traffic; however, next-generation supercomputers and terabit/second communications ...
    June 1, 2010
    (Courtesy of VHESC)
    FIGURE 1. A new solar cell concept uses spectrally sorted sunlight to improve solar conversion efficiency values beyond 40%.
    Advances in photonics and materials science are enabling researchers to harness sunlight in new ways that go well beyond conventional photovoltaics.
    June 1, 2010
    FIGURE 1. Common sources of noise and vibration are shown here. They range from frequencies as low as 0.1 Hz to more than 20 kHz.
    Vibration site surveys can tell you a lot about how to specify equipment for vibration isolation in your laboratory.
    June 1, 2010
    (Courtesy of Queen's University)
    A schematic of the photonic pickup shows the laser diode (bottom), photodiode (left), fiber (yellow lines), optical circulator (yellow circle), and F-P cavity (on guitar). The cavity is defined by two FBGs.
    Hans-Peter Loock and his colleagues at Queen's University were experimenting with the use of fiber Bragg gratings (FBGs) as acoustic sensors for laser-induced photoacoustic spectroscopy...
    June 1, 2010
    (Courtesy of MIT)
    A perfectly reflecting mirror with a width of 4.0 units has a smooth bump 0.2 units high. An isotropic-metamaterial optical cloak 1.5 units high with a varying refractive index (color scale) is designed to perfectly hide the bump. For a light ray incoming at a 45° angle and striking near the top of the bump, the cloak successfully points the outgoing ray in the right direction, but fails at placing the outgoing ray at the proper exit point.
    Scientists at the Massachusetts Institute of Technology (MIT) have determined that a recently popular approach to designing an invisibility cloak doesn't produce quite what was...
    June 1, 2010
    Pennwell web 450 232
    A simple surface-metrology approach developed by researchers at the University of Illinois at Urbana-Champaign allows the user to easily obtain the surface profile of certain ...
    June 1, 2010
    (Courtesy of Forza Silicon)
    FIGURE 1. Signal-to-noise ratio (SNR) collapse for two integration times (a) and eight integration times (b) for a sensor with 20 K full-well and 5 electrons of noise.
    As CMOS pixel sizes are aggressively scaled down to increase resolution, high-dynamic-range (HDR) techniques are required to maintain or even enhance imager performance
    June 1, 2010
    FIGURE 1. Indium gallium nitride (InGaN)-based laser diodes were first demonstrated in 1995. Since then their output has steadily progressed toward the green.
    The advantages of direct-emitting green laser diodes—among them high efficiency and lifetime—are expected to expand visible laser applications and enable growth in new areas of...
    June 1, 2010
    (Courtesy of FASORtronics)
    FIGURE 1. The 50 W FASOR beam from the Starfire Optical Range 3.5 m telescope creates a guidestar in the mesospheric sodium layer on Apr. 26, 2005. The FASORtronics commercial design (inset) with and without the enclosure panels shows the single-frequency IR laser modules and the sum-frequency generator.
    Two types of sodium-guidestar laser with phenomenally high optical power have been separately conceived and developed, one at the AFRL's Starfire Optical Range and one at the ...
    June 1, 2010
    71325
    The 2010 CLEO/Laser Focus World Innovation Awards program is designed to honor the most timely, groundbreaking products in the field of photonics nd laser science.
    June 1, 2010
    (Courtesy of AdvR)
    Three different 2D patterns produced by the output of two orthogonal beam deflectors were captured with a CCD camera. The same deflector technology is used in a 1 × 35 fiber-in, fiber-out EO switch (below).
    Poled electro-optic crystals are at the core of a compact fiber-optic switch design that can handle watts of optical power at megahertz switching speeds.
    June 1, 2010
    FIGURE 1. Raman lidar picks up Rayleigh scattering from air molecules at the 355 nm fundamental wavelength of the laser transmitter, and Raman scattering at longer wavelengths from oxygen, nitrogen, and water vapor molecules. Note the scattering is on a relative log scale. Comparing the scattering from water vapor, which varies widely, to that of nitrogen, which is uniform in air, gives the mixing ratio.
    A ground-based network of 400 lidar stations would collect data on atmospheric properties for use in weather forecasting and climate research.
    June 1, 2010
    (Courtesy of Specialised Imaging Limited)
    FIGURE 1. Specialised Imaging uses a 16-channel beamsplitter-based design, with a compact folded-optic architecture and an intensified CCD sensor for ultrahigh-speed imaging.
    Ultrahigh-speed framing cameras have evolved into single plug-and-play systems using beamsplitters and wavelength-selective components in a unique folded-optics architecture.
    June 1, 2010