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Infrared
Beginner
Thermal radiation sensed as heat.
Wavelengths 700 nm–1 mm emitted by warm bodies. Used in remote controls, thermal imaging and heating. Humans emit at ~10 μm.
Night-vision cameras.
Glass blocks far infrared.
In more detail
Infrared radiation has wavelengths just longer than visible light and is emitted by warm objects. It is felt as heat and used in remote controls, thermal imaging and communications.
Real-world uses
- Thermal cameras detect infrared emitted by warm bodies.
- Remote controls send infrared pulses to appliances.
- Thermal cameras and TV remote controls use infrared light to detect heat or send signals.
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Frequently asked questions
Why do we feel infrared as heat?
Infrared is absorbed by the skin and converted to thermal energy.
Can we see infrared?
Not with the eye, but cameras and sensors can detect it.
Is infrared dangerous?
Infrared is mainly felt as heat, but very intense sources can burn the skin or damage the eyes.
Related topics in AC Circuits & EM Waves
EM spectrum · Radio waves · Microwaves · Visible light · Ultraviolet · X-rays