Special Coverage

Soft Robot “Walks” on Any Terrain
Defense Advanced Research Projects Agency
Using Microwaves to Produce High-Quality Graphene
Transducer-Actuator Systems for On-Machine Measurements and Automatic Part Alignment
Wide-Area Surveillance Using HD LWIR Uncooled Sensors
Heavy Lift Wing in Ground (WIG) Cargo Flying Boat
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

Improved Approach to Exoplanet Coronagraphy

Visible nulling coronagraphy and interferometry requires that the wavefront errors be held to unprecedented precision in the presence of environmental disturbances. A Null Diversity algorithm is used to first attain the precision, but it does not execute at high enough temporal bandwidth to hold the precision for long periods of time (hours). The environmental changes, mostly vibration and jitter with some thermal drift, can be rapidly varying and thus require a fast control algorithm. To perform rapid control, an algorithm, based upon a series of approximations, has been developed and simulated at NASA Goddard Space Flight Center for the sensing and control, in closed loop, of extremely precise wave-front errors in an interferometer. It operates over the range of ~5 nanometers rms down to <100 picometers rms in closed loop at high bandwidth (~20 Hz) and is used to hold (i.e. maintain) the requisite wavefront error.

Posted in: Briefs, Photonics, Mathematical models, Lasers, Lasers, Vibration, Vibration

Apparatus and Method for a Light Direction Sensor

This invention, developed at NASA's Goddard Space Flight Center, was originally conceived as a high-accuracy, high-sensitivity, bi-axial Sun angle sensor, but has also been proposed for applications involving the general field of precisely measuring the direction in which light travels toward the sensor. It has applications in spacecraft navigation, formation flying in space, space beacons, and automotive collision avoidance.

Posted in: Briefs, Photonics, Measurements, Sensors and actuators, Sensors and actuators, Sun and solar

Apparatus and Method for Creating a Photonic Densely Accumulated Ray-Point

NASA's Langley Research Center has discovered a new approach to achieving a laser focal point size much smaller than the wavelength of light used, and smaller than that obtained using conventional micro zone plate lenses. The Photonic Densely Accumulated Ray-poinT (DART) technology relies on phase contrast along with interference phenomena, with or without the use of a micro zone plate lens. Coupled with the extremely small spot size, the technology also provides very high laser energy density at the pseudo focal point surrounded by destructive interference, thereby enabling a range of potential useful applications such as laser processing, lithography, nanofabrication, and optical data storage.

Posted in: Briefs, Photonics, Lasers, Waveguides, Lasers, Waveguides, Refractory materials

Optical Fiber Sensors vs. Conventional Electrical Strain Gauges for Infrastructure Monitoring Applications

Public infrastructure, including bridges, pipelines, tunnels, foundations, roadways, dams, etc., is subject to factors that can degrade it or lead to malfunctions. These structural problems can be the result of deterioration, improper construction methods, seismic activity, nearby construction work, etc. Although electrical strain gauges have long been used for monitoring structural changes, they sometimes lack the durability and integrity necessary to provide accurate, actionable information over extended periods. The applications in this white paper demonstrate how optical fiber sensors can offer a variety of economic and performance advantages.

Posted in: White Papers, Fiber Optics, Optics, Sensors

Laser Diode Modules

BEA Lasers (Elk Grove Village, IL) has introduced two new low-profile additions to their rugged MIL Series of laser diode modules. The new MIL RA Model features a right angle, and the new MIL Compact Model features a straight housing. Both new models utilize a low profile 3/8” rugged laser housing, fitted with a M12 connector, 2 meter long PVC jacketed cable, and integrated power supply. The optional sensor-style bracket, or multi-adjustable “LB” bracket, completes the laser system. The new MIL Series laser diode modules are offered with standard 515nm (green) or standard 635nm (red), with 1mW or 5mW.

Posted in: Products, Products, Lasers & Laser Systems

Single-Frequency Lasers

LASOS (Jena, Germany) has expanded its range of single-frequency laser sources from the ultra-violet through the red. Wavelength-dependent power levels up to 300 mW are available, with spectral linewidth values less than 1 MHz. Products include diode-pumped solid-state devices from the UV through red. These field-proven sources maintain excellent spectral and power performance for applications including Raman, Holography and Precision Metrology.

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Posted in: Products, Products, Lasers & Laser Systems

Physics, Photosynthesis and Solar Cells

A University of California, Riverside assistant professor has combined photosynthesis and physics to make a key discovery that could help make solar cells more efficient. Nathan Gabor is focused on experimental condensed matter physics, and uses light to probe the fundamental laws of quantum mechanics. But, he got interested in photosynthesis when a question popped into his head in 2010: Why are plants green? He soon discovered that no one really knows.

Posted in: INSIDER, Materials, Photonics

New Crystal Structure Holds Promise for Optoelectronic Devices

A Florida State University research team has discovered a new crystal structure of organic-inorganic hybrid materials that could open the door to new applications for optoelectronic devices like light-emitting diodes and lasers.

Posted in: INSIDER, Lasers & Laser Systems, Optics, Photonics

Light Can Switch on Topological Materials

Theoretical physicists at the Department of Energy’s SLAC National Accelerator Laboratory used computer simulations to show how special light pulses could create robust channels where electricity flows without resistance in an atomically thin semiconductor. If this approach is confirmed by experiments, it could open the door to a new way of creating and controlling this desirable property in a wider range of materials than is possible today.

Posted in: INSIDER, Photonics

Polymeric Systems Bring Clarity to Optical Applications

Whereas some optical assembly applications require optical clarity across a certain wavelenth, others require an opaque coating. Optical grade epoxies, silicones and UV curable coatings provide the versatility to adhere well to a wide variety of substrates and the critical performance properties necessary. Learn more about optical transmission, refractive indices, temperature and humidity testing, and more, and the roles these measurements in choosing an effective and reliable optical polymer system.

Posted in: White Papers, Photonics

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