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Operation of the NIST Ambient Radiation Thermometer, which is approximately 60 cm (24 in. long (1) Infrared (IR) light from a fixed-temperature calibrated source (at right, not shown) enters the thermometer enclosure through this lens, which focuses the radiation onto a “field stop,” analogous to the f-stop aperture in photography. (2) A circular metal chopper slices the IR beam into a sequence of pulses. (3) The first lens inside the central cylinder converts the light from the field stop to a parallel beam. (4) The light passes through this insulated cylinder about 30 cm (12 in.) long which is temperature-controlled by a feedback system. Stray radiation is blocked by another stop. (5) A second lens focuses the light onto a pyroelectric detector. (6) The detector output is routed to an amplifier that boosts the signal to readily readable levels. Credit: NIST

Measuring temperature with invisible light

The most common way to check if someone has a fever without a thermometer is to feel the forehead or neck with the back...
Model of nanowire-based light-emitting diode showing that adding a bit of aluminum to the shell layer (black) directs all recombination of electrons and holes (spaces for electrons) into the nanowire core (multicolored region), producing intense light. Credit: NIST

Researchers Boost Intensity of Nanowire LEDs

Nanowire gurus at the National Institute of Standards and Technology (NIST) have made ultraviolet light-emitting diodes (LEDs) that, thanks to a special type of...
New antenna evaluation method could help boost 5G network capacity

New antenna evaluation method could help boost 5G network capacity

5G will be a system of systems that extend far beyond radio. 5G systems will avoid crowded conventional wireless channels by using higher, millimeter-wave frequency...
Simplified experimental scheme.

NIST atomic clocks now keep time well enough to improve models of Earth

A newly developed experimental atomic clock can precisely tick to improve timekeeping and navigation. It additionally can detect signals from gravity, the early universe and...
a microscopic gear and actuator in a MEMS (microelectromechanical system) device. A tiny actuator moves back and forth in a ratcheting motion that drives the rotation of a microscopic ring gear. To track the actuator's motion, researchers attached fluorescent particles to the actuator. Using the light-emitting particles, researchers were able to track displacements as small as billionths of a meter, and rotations as tiny as several millionths of a radian at a rate of 1000 times per second. Credit: Jennifer Lauren Lee/NIST

How microscopic machines can fail within seconds?

To what extent can tiny gears and other microscopic moving parts last before they destroy? What are the warning signs that these segments are...
New device widens light beams by 400 times

New device widens light beams by 400 times

Scientists at the National Institute of Science and Technology (NIST) have developed an efficient converter that enlarges the diameter of a light beam by...
A scanning electron micrograph showing a cluster of silver nanoparticles released by scratching a nanosilver-infused cutting board. The cluster is approximately 900 nanometers across, or about the size of a typical bacterium. Credit: NIST

Do kitchen items shed antimicrobial nanoparticles after use?

Silver nanoparticles measuring between one and 100 nanometers (billionth of a meter) in size are being incorporated outside the United States into a variety...
Kilogram No. 20, in the U.S., is one of several “working standards.” Credit: Science Source

Redefining the kilogram: A turning point for humanity

The kilogram is the base unit of mass in the International System of Units (SI), and is defined as being equal to the mass...
False-color images showing variations in atom numbers (1 to 5 atoms, left to right) and density in different lattice cells of JILA’s strontium lattice atomic clock. JILA researchers observed shifts in the clock’s frequency that arise from the emergence of multi-particle interactions when three or more atoms occupy a single cell. Credit: Aki Goban, Ye group/JILA

Signs of interactive form of quantum matter

For the first ever time, JILA scientists have confined groups of a couple of atoms and precisely estimated their multi-particle cooperations inside an atomic clock....