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  • Volume 40, Issue 4
  • Volume 40, Issue 4

    More content from Volume 40, Issue 4

    Th 146458
    "Immersion" was the word at the SPIE Microlithography 2004 meeting (Santa Clara, CA; Feb. 22–27) as chipmakers put off the tough climb to 157-nm optical lithography and opted ...
    April 1, 2004
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    Researchers at the Georgia Institute of Technology (Georgia Tech; Atlanta, GA) are working with a local bakery to develop a machine-vision system to automatically inspect freshly...
    April 1, 2004
    Rofin-Sinar acquires Swedish fiberoptics firm; IDS expands portfolio with patent on medical imaging system; Report optimistic on future of long-wavelength lasers; MORE...
    April 1, 2004
    Th 146478
    In a development that may one day help in the fabrication of nanometer-scale optical devices, engineers at Nippon Telegraph and Telephone Corp. (NTT: Tokyo, Japan) have created...
    April 1, 2004
    Arasor acquires Lightbit and IOA; BU opens optics lab; Bookham partners on MEMS design; MORE...
    April 1, 2004
    BU partners with French optics consortium; Adaptive optics locate larger stars; Melles opens coating technology center; MORE...
    April 1, 2004
    Two groups of researchers have advanced the use of electrowetting droplets for displays, with one demonstrating a new way of exploiting the optical geometry of the liquid used...
    April 1, 2004
    Th 146607
    AFM is a well-established surface-analysis tool, but researchers are also using it to manipulate matter on the molecular and atomic scale.
    April 1, 2004
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    Biophysicists from Cornell University (Ithaca, NY) have joined forces with a chemist from Université de Rennes (Rennes, France) to tackle one of the biggest optical-imaging challenges...
    April 1, 2004
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    When a planet with an atmosphere passes in front of a star (an event known as an occultation), earthbound scientists can glean information about the planet's atmosphere by examining...
    April 1, 2004
    Th 146474
    In a Rydberg atom (or molecule), an outer electron is excited to a high quantum state without being ionized, resulting in an atom with a very large electron cloud.
    April 1, 2004
    Th 146531
    The reliance of modern society on science and technology has created a serious and growing need for a large high-technology workforce and a technically literate population.
    April 1, 2004
    Th 146559
    Active-photonic-lattice distributed-feedback lasers emit a diffraction-limited surface-normal beam. These lasers can be coherently combined into arrays that could potentially ...
    April 1, 2004
    FIGURE 1. A lab on a chip consists of a disposable slide containing microfluidic channels (top two layers), light-emitting diodes backed by reflectors to prevent crosstalk (central layers), and a silicon detector filtered using a film of cadmium sulfide (CdS; bottom three layers).
    A team at the University of California–Berkeley has devised a system that can perform light-induced fluorescence spectroscopy, has an area less than 1 cm2, and is less than 1....
    April 1, 2004
    Th 146549
    Wavefront sensing for adaptive optics (AO) has become an essential component in building large ground-based telescopes and telescope interferometers for 21st century astronomy...
    April 1, 2004
    FIGURE 1. In a silicon-waveguide phase shifter, n-doped silicon is deposited atop an insulator. Optical confinement is provided by the oxide layers surrounding the p-doped polysilicon rib. The polysilicon is bordered on the sides by thick oxide layers, on the bottom by a thin oxide gate layer about 12 nm thick, and by an oxide layer (not shown) on top. When voltage is applied, positive charge carriers move to the gate, changing the refractive index of the waveguide and causing a phase shift. The phase shifter can be used in a Mach-Zehnder interferometer (inset), which converts the phase shift to intensity modulation.
    A fast modulator made of silicon (Si) may make researchers take another look at the material, which has been largely forsaken by the optoelectronics industry in favor of other...
    April 1, 2004
    Kodak to divest remote-sensing business; Omron picks up KOA backlight business; Camera looks for damage on Space Shuttle; MORE...
    April 1, 2004
    Th 146519
    Using technology based on a continuous-wave near-IR imager first demonstrated in 1996 by Britton Chance, emeritus faculty at University of Pennsylvania (Philadelphia, PA), and...
    April 1, 2004
    FIGURE 1. Nomarski-microscope images show the onset (left) and progression (right) of laser-induced damage within voids and pinholes in a conventional 193-nm mirror coating. These mirrors exhibit moderate and severe damage from laser exposure. In both instances, laser-induced damage started within microscopic voids in the coating. The severe damage at right occurred after 240,000 pulses at 225 mJ/cm2 at a 100-Hz repetition rate.
    The best way to design and test coatings for use at 193 nm relies on two approaches: one for high pulse energy and low repetition rate, and the other for low pulse energy and ...
    April 1, 2004
    Th 146439
    Terahertz radiation carries information; QD and QW lasers face off; Attosecond pulses probe atoms' inner dynamics; MORE...
    April 1, 2004
    Nanotechnologist Ralph E. Merkle (see www.merkle.com) has described current manufacturing methods as being akin to building a castle out of Lego blocks while wearing boxing gloves...
    April 1, 2004
    FIGURE 1. Researchers at the University of Jena will be among the many presenters at this year's CLEO technical sessions. A chirped-pulse amplifier they have developed starts with 250-fs 1040-nm pulses from a modelocked Yb:KGW laser. A 1.9-m-long step-index single-mode fiber prestretches the pulse. Next, it is amplified in a 2.1-m-long air-clad microstructured ytterbium-doped large-mode-area fiber (pumped by a 976-nm laser diode). Finally, the amplified pulses are recompressed into positively chirped pulses in 2 m of air-guiding photonic-bandgap fiber.
    Technical sessions will reveal what is ahead in the areas of semiconductor emitters, displays, nonlinear and ultrafast optics, sensing, and biological applications.
    April 1, 2004
    In a small market, solid-state lighting matches up well with solid-state sensors.
    April 1, 2004
    Th 146457
    Shuji Nakamura's seemingly single-handed invention of practical gallium nitride–based blue and UV lasers and light-emitting diodes (LEDs) during his stint at Nichia (Kaminaka,...
    April 1, 2004
    FIGURE 1. The small, bright arc of a short-arc lamp allows for great flexibility in shaping the emitted light for illumination and other uses. Proper power-supply design is crucial to the stability of an arc lamp's optical output.
    The optical output of a short-arc lamp is kept stable in the short term by good power-supply design, and in the long term by a closed-loop light-intensity control system.
    April 1, 2004
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    Communication is the key to effectively carrying out optical design projects while shortening design cycles and reducing manufacturing costs because it enables the customer and...
    April 1, 2004
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    Combined with laser triangulation, a vision system determines the saw cuts that maximize the usable lumber obtained from tree trunks.
    April 1, 2004
    Th 147219
    Regional phone companies in the United States have left fiber rollout to others, but as bandwidth demands increase, fiber to the home is gradually gaining momentum.
    April 1, 2004
    A patient is about to deposit a sputum/aerosol sample into a disposable collection device. The sample collector is then inserted into an optical reader to check for pathogens such as tuberculosis bacteria (inset).
    A laser-based breathalyzer system may make painful, under-the-skin testing for tuberculosis (TB) a relic of the past.
    April 1, 2004