Logo
 
Reference terms from Wikipedia, the free encyclopedia
 

Passive infrared sensor

A passive infrared sensor (PIR sensor) is an electronic sensor that measures infrared (IR) light radiating from objects in its field of view. They are most often used in PIR-based motion detectors. PIR sensors are commonly used in security alarms and automatic lighting applications.

PIR sensors detect general movement, but do not give information on who or what moved. For that purpose, an imaging IR sensor is required.

PIR sensors are commonly called simply "PIR", or sometimes "PID", for "passive infrared detector". The term passive refers to the fact that PIR devices do not radiate energy for detection purposes. They work entirely by detecting infrared radiation (radiant heat) emitted by or reflected from objects.

 
Note:   The above text is excerpted from the Wikipedia article Passive infrared sensor, which has been released under the GNU Free Documentation License.
 

Check out these latest Nanowerk News:

 

Light color controls a photonic synapse that remembers and forgets

Researchers built a photonic synapse that strengthens or erases memory by light color, using a defect to mimic the brain's balanced learning.

Twisting 2D materials brings quantum light control closer to reality

Researchers show that twisting atom-thin boron nitride layers can tune quantum light emitters, offering new control for quantum technologies.

Open-air synthesis yields atom-precise iridium catalyst

A simple air-based method produces stable 15-atom iridium nanoclusters that outperform commercial catalysts for green hydrogen production.

Molecular simulations reveal why nanodrops spread

Simulations reveal why water nanodrops spread on surfaces: molecular structure at the contact line flips line tension, reshaping nanoscale wetting.

AI system monitors 2D semiconductor manufacturing at the atomic layer

Researchers combined low-temperature plasma processing with machine learning to synthesize and etch 6-inch MoS2 and WS2 wafers and predict film thickness in real time.

Paint it blacker: Carbon nanotube coating could make cars ultra-black

A new ultra-black automotive coating absorbs 99.9% of visible light, creating a deeper black finish that could be used on future luxury cars.

Real-time microscopy reveals how semiconductor nanowires grow, and how bismuth seeds can speed their formation

Scientists captured tellurium nanowire growth in liquid in real time, showing seed formation, material competition and bismuth-assisted deposition.

New nanotube membranes reveal unusually fast lithium-ion transport

Boron nitride nanotube membranes rapidly and selectively transport lithium ions, boosting prospects for clean energy, lithium recovery and molecular separation.

3D-printed glowing ceramics could shrink future photonic devices

Laser 3D printing turns YAG:Ce ceramics into precise, light-emitting microstructures for compact sensors, LEDs, optical circuits and radiation detectors.

How does light turn into motion within a metal?

Scientists have shown that ultrashort optical laser pulses can trigger extremely rapid lattice vibrations in periodically layered metal structures - not primarily by heating the atomic lattice, but through the pressure exerted by hot electrons.