Special Coverage

Technique Provides Security for Multi-Robot Systems
Bringing New Vision to Laser Material Processing Systems
NASA Tests Lasers’ Ability to Transmit Data from Space
Converting from Hydraulic Cylinders to Electric Actuators
Automating Optimization and Design Tasks Across Disciplines
Vibration Tables Shake Up Aerospace and Car Testing
Supercomputer Cooling System Uses Refrigerant to Replace Water
Computer Chips Calculate and Store in an Integrated Unit
Electron-to-Photon Communication for Quantum Computing

On-Wafer Measurement of a Silicon-Based CMOS VCO at 324 GHz

Compact, low-power, electronically tunable submillimeter-wave local oscillators are now feasible.

The world’s first silicon- based complementary metal oxide/semi- conductor (CMOS) integrated-circuit voltage-controlled oscillator (VCO) operating in a frequency range around 324 GHz has been built and tested. Concomitantly, equipment for measuring the performance of this oscillator has been built and tested. These accomplishments are intermediate steps in a continuing effort to develop low-power- consumption, low-phase-noise, electronically tunable signal generators as local oscillators for heterodyne receivers in submillimeter-wavelength (frequency > 300 GHz) scientific instruments and imaging systems. Submillimeter-wavelength imaging systems are of special interest for military and law-enforcement use because they could, potentially, be used to detect weapons hidden behind clothing and other opaque dielectric materials. In comparison with prior submillimeter-wavelength signal generators, CMOS VCOs offer significant potential advantages, including great reductions in power consumption, mass, size, and complexity. In addition, there is potential for on-chip integration of CMOS VCOs with other CMOS integrated circuitry, including phase-lock loops, analog-to-digital converters, and advanced microprocessors.

Posted in: Briefs, TSP, Semiconductors & ICs, Amplifiers, Imaging and visualization, Integrated circuits, Semiconductor devices, Silicon alloys
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High-Voltage, Asymmetric-Waveform Generator

This circuit would be optimized for a capacitive load.

The shapes of waveforms generated by commercially available analytical separation devices, such as some types of mass spectrometers and differential mobility spectrometers are, in general, inadequate and result in resolution degradation in output spectra. A waveform generator was designed that would be able to circumvent these shortcomings. It is capable of generating an asymmetric waveform, having a peak amplitude as large as 2 kV and frequency of several megahertz, which can be applied to a capacitive load. In the original intended application, the capacitive load would consist of the drift plates in a differential-mobility spectrometer. The main advantage to be gained by developing the proposed generator is that the shape of the waveform is made nearly optimum for various analytical devices requiring asymmetric-waveform such as differential-mobility spectrometers. In addition, this waveform generator could easily be adjusted to modify the waveform in accordance with changed operational requirements for differential-mobility spectrometers.

Posted in: Briefs, TSP, Electronics & Computers, Capacitors, High voltage systems, Spectroscopy, Switches, Test equipment and instrumentation
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Group-III Nitride Field Emitters

Growing group-III nitride films spontaneously split into columns.

Field-emission devices (cold cathodes) having low electron affinities can be fabricated through lattice- mismatched epitaxial growth of nitrides of elements from group III of the periodic table. Field emission of electrons from solid surfaces is typically utilized in vacuum microelectronic devices, including some display devices. The present field-emission devices and the method of fabricating them were developed to satisfy needs to reduce the cost of fabricating field emitters, make them compatible with established techniques for deposition of and on silicon, and enable monolithic integration of field emitters with silicon-based driving circuitry.

Posted in: Briefs, Electronics & Computers, Electronic equipment, Displays, Fabrication
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Magic-T Junction Using Microstrip/Slotline Transitions

Economical broadband junctions have potential utility in diverse microwave systems.

An improved broadband planar magic-T junction that incorporates microstrip/slotline transitions has been developed. In comparison with a prior broadband magic-T junction incorporating microstrip/slotline transitions, this junction offers superior broadband performance. In addition, because this junction is geometrically simpler and its performance is less affected by fabrication tolerances, the benefits of the improved design can be realized at lower fabrication cost. There are potential uses for junctions like this one in commercial microwave communication receivers, radar and polarimeter systems, and industrial microwave instrumentation.

Posted in: Briefs, Electronics & Computers, Connectors and terminals, Waveguides, Fabrication
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Improved Gas Filling and Sealing of an HC-PCF

Compact hermetic joint is formed to seal connectorized all-fiber gas reference cell.

An improved packaging approach has been devised for filling a hollow-core photonic-crystal fiber (HC-PCF) with a gas, sealing the HC-PCF to retain the gas, and providing for optical connections and, optionally, a plumbing fitting for changing or augmenting the gas filling. Gas-filled HC-PCFs can be many meters long and have been found to be attractive as relatively compact, lightweight, rugged alternatives to conventional gas-filled glass cells for use as molecular-resonance frequency references for stabilization of lasers in some optical-metrology, lidar, optical-communication, and other advanced applications. Prior approaches to gas filling and sealing of HC-PCFs have involved, variously, omission of any attempt to connectorize the PCF, connectorization inside a vacuum chamber (an awkward and expensive process), or temporary exposure of one end of an HC-PCF to the atmosphere, potentially resulting in contamination of the gas filling. Prior approaches have also involved, variously, fusion splicing of HC-PCFs with other optical fibers or other termination techniques that give rise to Fresnel reflections of about 4 percent, which results in output intensity noise.

Posted in: Briefs, TSP, Manufacturing & Prototyping, Fiber optics, Gases, Refractory materials, Reliability
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Thermal Spray Formation of Polymer Coatings

This innovation forms a sprayable polymer film using powdered precursor materials and an in-process heating method. This device directly applies a powdered polymer onto a substrate to form an adherent, mechanically-sound, and thickness-regulated film. The process can be used to lay down both fully dense and porous, e.g., foam, coatings. This system is field-deployable and includes power distribution, heater controls, polymer constituent material bins, flow controls, material transportation functions, and a thermal spray apparatus.

Posted in: Briefs, Manufacturing & Prototyping, Coatings, colorants, and finishes, Polymers
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Embedded Computing Options Meet Rugged Industrial Requirements

While industrial applications typically require high levels of reliability, availability, ruggedness, and longevity, there often is a set of unique system requirements dependent upon the specific goals of the system. For instance, an industrial automation application may call for a particular I/O interface or the ability to support custom control software.

Posted in: Articles, Electronics & Computers, Automation
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Making More-Complex Molecules Using Superthermal Atom/Molecule Collisions

Atoms adsorbed on cold surfaces react with energetic impinging atoms.

A method of making more-complex molecules from simpler ones has emerged as a by-product of an experimental study in outer-space atom/ surface collision physics. The subject of the study was the formation of CO2 molecules as a result of impingement of O atoms at controlled kinetic energies upon cold surfaces onto which CO molecules had been adsorbed. In this study, the O/CO system served as a laboratory model, not only for the formation of CO2 but also for the formation of other compounds through impingement of rapidly moving atoms upon molecules adsorbed on such cold interstellar surfaces as those of dust grains or comets. By contributing to the formation of increasingly complex molecules, including organic ones, this study and related other studies may eventually contribute to understanding of the origins of life.

Posted in: Briefs, TSP, Materials, Carbon dioxide, Fabrication, Test procedures
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Image Sensors Provide Mission-Critical Data for Space Flight

Kodak CCD image sensors Eastman Kodak, Image Sensor Solutions Rochester, NY 585-722-4385 www.kodak.com/go/imagers

Kodak digital technology was used on the Space Shuttle Discovery, which was launched on May 28, to capture critical images and help safeguard the well-being of shuttle astronauts during re-entry back to Earth. The image sensors are a key component of the Orbiter Boom Sensor System (OBSS), an inflight imaging system attached to the end of a 50-foot robotic arm used by shuttle astronauts to scan the underside of the orbiter for possible damage before landing.

Posted in: Application Briefs, Imaging, Sensors, Imaging and visualization, Sensors and actuators, Data management, Spacecraft
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Image of Spacecraft Landing on Mars Captured by Image Sensors

e2v CCD image sensors e2v technologies plc Elmsford, NY 914-592-6050 www.e2v.com

NASA’s Mars Reconnaissance Orbiter (MRO) is currently on Mars using the probe’s High Resolution Imaging Science Experiment (HiRISE) instrument to gather data on the planet’s climate, composition, and surface features. On May 25, 2008, e2v CCD image sensors incorporated into the HiRISE captured an image of NASA’s Phoenix Mars Lander suspended from its parachute, as the lander successfully arrived on Mars. This is the first time a spacecraft has captured an image of another spacecraft landing on a planetary body. HiRISE normally points downwards, but the whole orbiter was tilted up in order to capture the image of the lander as it approached Mars.

Posted in: Application Briefs, Imaging, Sensors, Imaging and visualization, Entry, descent, and landing, Spacecraft
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