Physical Sciences

Multi-Source Autonomous Response for Targeting and Monitoring of Volcanic Activity

This concept has great relevance to Earth science and future planetary exploration. The study of volcanoes is important for both purely scientific and human survival reasons. From a scientific standpoint, volcanic gas and ash emissions contribute significantly to the terrestrial atmosphere. Ash depositions and lava flows can also greatly affect local environments. From a human survival standpoint, many people live within the reach of active volcanoes, and therefore can be endangered by both atmospheric (ash, debris) toxicity and lava flow.

Posted in: Physical Sciences, Sensors, Briefs, TSP

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Deployable Fresnel Rings

This antenna technology can be used by first-responders and soldiers requiring cellular range extension or satellite links to handheld devices. Deployable Fresnel rings (DFRs) significantly enhance the realizable gain of an antenna. This innovation is intended to be used in combination with another antenna element, as the DFR itself acts as a focusing or microwave lens element for a primary antenna. This method is completely passive, and is also completely wireless in that it requires neither a cable, nor a connector from the antenna port of the primary antenna to the DFR.

Posted in: Physical Sciences, Briefs, TSP

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Transition-Edge Hot-Electron Microbolometers for Millimeter and Submillimeter Astrophysics

New instruments promise to expand the investigation of cosmic microwave background radiation and its polarization to get better insight into the evolution of the universe. The millimeter and the submillimeter wavelengths of the electromagnetic spectrum hold a wealth of information about the evolution of the universe. In particular, cosmic microwave background (CMB) radiation and its polarization carry the oldest information in the universe, and provide the best test of the inflationary paradigm available to astronomy today. Detecting gravity waves through their imprint on the CMB polarization would have extraordinary repercussions for cosmology and physics.

Posted in: Physical Sciences, Briefs, TSP

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V-Assembly Dual-Head Efficiency Resonator (VADER) Laser Transmitter

The combined features form a unit with new performance levels. A complete demonstration breadboard unit for advanced development as a high-TRL (technology readiness level) system has been constructed and characterized. Infusion of several new component technologies, such as ceramic:YAG material and high-power laser diode arrays (LDAs), combined with a proprietary minimal part count architecture, has resulted in dramatic performance gains. The proprietary dual-head configuration employs a pair of side-pumped laser slabs, optically in series in the cavity, but at opposing polarization orientations. This promises tremendous power range scalability, simplified and symmetrical thermal lens control, unprecedented stored energy extraction efficiency, and inherent diffraction limited TEM00 beam quality.

Posted in: Tech Briefs, Physical Sciences, Photonics, Briefs, TSP

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Twin Head Efficient Oscillator Development for the ACE Multi- Beam Lidar and 3D-Winds

This technology is applicable to atmospheric lidar, Doppler wind measurements, interplanetary laser communications, and materials processing. The Twin Head Efficient Oscillator (THEO) concept uses a pair of smaller, identical laser pump modules, oriented to remove asymmetrical thermo-optical effects typical in single-slab lasers such as HOMER (High Output Maximum Efficiency Resonator), MLA (Mercury Laser Altimeter), LOLA Lunar Orbiter Laser Altimeter, and GLAS (Geoscience Laser Altimeter), while simultaneously increasing efficiency and lifetime. This creates 100+ mJ pulses in an oscillator-only design, with reduced risk of optical damage, record efficiency, high stability, long life, and high TEM00 beam quality typical of much smaller rod-based cavities. Near-field-beam quality is critical to efficient second harmonic generation (SHG 532 nm), which is typically poor in slab-based Nd:YAG lasers.

Posted in: Physical Sciences, Photonics, Briefs, TSP

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Planetary Polarization Nephelometer

Instrument provides more detailed information on aerosols encountered in a planetary environment. Aerosols in planetary atmospheres have a significant impact on the energy balance of the planets, yet are often poorly characterized. An in situ instrument was developed that would provide more diagnostic information on the nature of aerosols it encountered if deployed on a planetary descent probe. Previous probe instruments only measured intensity phase functions, but much particle ambiguity remains with only this information. Adding the polarization phase function greatly reduces particle characteristic ambiguities, but also adds more challenges in designing a measurement approach. Laboratory instrumentation to measure intensity and polarization phase functions have existed since the early 1970s, but these instruments employed quarter-wave plates and Pockels cells to modulate the illuminating beam and the scattered light to isolate the intensity and polarization phase functions. Both of these components are unstable except under tightly controlled thermal conditions. This solution avoids the use of thermally sensitive components such as quarter- wave plates or Pockels cells, and avoids requiring the detectors to be placed around the sensing volume.

Posted in: Physical Sciences, Photonics, Briefs, TSP

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Optical Tunable-Based Transmitter for Multiple High-Frequency Bands

Applications include satellite communications, optical communications networks, and RF antenna applications. The purpose of this innovation is to be able to deliver, individually or simultaneously, multiple microwave high-frequency bands including, but not limited to, L (1.5 GHz), C (7 GHz), X (8.4 GHz), Ku (14.5 GHz), Ka (32 GHz), and Q (38 GHz) frequencies at high data rates and with minimal hardware, particularly for use in satellite-to-satellite communications applications. Additionally, this innovation would be a satellite-based transmitter with a significant reduction in weight, mass, and power when compared to current, conventional technologies.

Posted in: Physical Sciences, Photonics, Briefs

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