infrared

infrared /in·fra·red/ (-red´) denoting electromagnetic radiation of wavelength greater than that of the red end of the spectrum, having wavelengths of 0.75–1000 μm; sometimes subdivided into long-wave or far i. (about 3.0–1000 μm) and short-wave or near i. (about 0.75–3.0 μm).

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in·fra·red (nfr-rd)

adj.

1. Of or relating to the range of invisible radiation wavelengths from about 750 nanometers, just longer than red in the visible spectrum, to 1 millimeter, on the border of the microwave region.

2. Generating, using, or sensitive to infrared radiation.

n.

Infrared light or the infrared part of the spectrum.

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infrared (IR) (inˑ·fr·redˈ),

n electromagnetic radiation of longer wavelength than red light in the range of 730 nanometres (nm) to about 1 millimetre (mm).

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infrared

denoting electromagnetic radiation of wavelength greater than that of the red end of the spectrum, having wavelengths of 0.75-1000 μm. Infrared rays are sometimes subdivided into long-wave or far infrared (about 3.0-1000 μm) and short-wave or near infrared (about 0.75-3.0 μm). They are capable of penetrating body tissues to a depth of 10 mm. Sources of infrared rays include heat lamps, hot water bottles, steam radiators and incandescent light bulbs.

Infrared rays are used therapeutically to promote muscle relaxation, to speed up the inflammatory process, and to increase circulation to a part of the body. See also heat.

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infrared (IR)

Radiant energy of wavelengths between the extreme red wavelengths of the visible spectrum and a wavelength of a few millimetres. The wave band comprising radiations between 780 and 1400 nm is referred to as IR-A. Excessive exposure to these radiations can cause visual loss (e.g. eclipse blindness) and cataract. The waveband comprising radiations between 1400 and 3000 nm is referred to as IR-B. Excessive exposure to these radiations can cause cataract and corneal opacity. The wave band comprising radiations between 3000 and 1 ✕ 10⁶ nm (or 1 mm) is referred to as IR-C. Excessive exposure to these radiations can cause cataract (heat-ray cataract). See eclipse blindness; absorptive lens; infrared optometer.