Special Coverage


Julia W. Loftis, Associate Chief for Information Systems Technology

NASA Goddard Space Flight Center, Greenbelt, MD Julia W. LoftisWhile a single, peer-to-peer rover can cover a large territory and gather a wealth of information, an entire fleet of rovers could cover even more ground. However, controlling multiple platforms poses a much different set of criteria. To answer the need to control and communicate with multiple vehicles doing a similar task, the Adaptive Sensor Fleet (ASF) software was developed by NASA researchers, and is able to coordinate several platforms at once. Julia Loftis oversaw the strategic planning of the project.

Posted in: Who's Who


Maple Mathematical Software

Maplesoft™, Waterloo, ON, Canada, has introduced Maple™ 11 mathematical software with a smart document environment that automatically captures technical knowledge in an electronic form that seamlessly integrates calculations, explanatory text and math, graphics, images, and sound. These live documents can be reused or shared across an organization. The smart document environment also includes the ability to use natural math notation in titles, legends, and labels, and annotation capabilities such as sketching, adding text and math, and drawing lines, shapes, and arrows.

Posted in: Products


Mobile Collection and Automated Interpretation of EEG Data

Diagnoses could be performed while subjects engaged in ordinary activities. A system that would comprise mobile and stationary electronic hardware and software subsystems has been proposed for collection and automated interpretation of electroencephalo- graphic (EEG) data from subjects in everyday activities in a variety of environments. By enabling collection of EEG data from mobile subjects engaged in ordinary activities (in contradistinction to collection from immobilized subjects in clinical settings), the system would expand the range of options and capabilities for performing diagnoses.

Posted in: Bio-Medical, Briefs, TSP


Thulium Puts Power Behind Eyesafe Fiber Lasers

One of the key advantages of fiber laser technology stems from the high conversion efficiency of the multimode pump radiation into high-brightness, single-mode laser light within the doped fiber lasing medium. Ytterbium-doped fiber lasers operating around 1μm often achieve around 80% pump- to-laser conversion efficiency and corresponding wall plug efficiencies over 25%, depending on the pump diodes used in the laser. As a result, high-power CW fiber lasers are more compact and require less cooling than a traditional solid-state laser of similar power.

Posted in: Articles, Features, ptb catchall, Photonics


Reactive Solders Improve Fiber Couplers and OE Bonding

Optical and optoelectronic (OE) devices are being rapidly integrated into many facets of everyday life. From telecommunications to sensor applications, these devices are expected to perform accurately and reliably for long periods of time.

Posted in: Application Briefs, Applications, ptb catchall, Photonics


Recirculation of Laser Power in an Atomic Fountain

Optical and electronic subsystems of a frequency standard can be simplified. NASA’s Jet Propulsion Laboratory, Pasadena, California A new technique for laser-cooling atoms in a cesium atomic fountain frequency standard relies on recirculation of laser light through the atom-collection region of the fountain. The recirculation, accomplished by means of reflections from multiple fixed beam-splitter cubes, is such that each of two laser beams makes three passes. As described below, this recirculation scheme offers several advantages over prior designs, including simplification of the laser system, greater optical power throughput, fewer optical and electrical connections, and simplification of beam power balancing.

Posted in: Photonics, Briefs, ptb catchall, Tech Briefs, Photonics


Simplified Generation of High-Angular-Momentum Light Beams

Inherent properties of a WGM resonator and optical fiber are exploited. NASA’s Jet Propulsion Laboratory, Pasadena, California A simplified method of generating a beam of light having a relatively high value of angular momentum (see figure) involves the use of a compact apparatus consisting mainly of a laser, a whispering-gallery-mode (WGM) resonator, and optical fibers. The method also can be used to generate a Bessel beam. (“Bessel beam” denotes a member of a class of non-diffracting beams, so named because their amplitudes are proportional to Bessel functions of the radii from their central axes. High-order Bessel beams can have high values of angular momentum.)

Posted in: Photonics, Briefs, ptb catchall, Tech Briefs, Photonics