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infrared radiation

IR radiation


optical radiation for which the wavelengths are longer than those for visible radiation

Note 1 to entry: For infrared radiation, the range between 780 nm and 1 mm is commonly subdivided into:
IR-A: 780 nm to 1 400 nm, or 0,78 μm to 1,4 μm;
IR-B: 1,4 μm to 3,0 μm;
IR-C: 3 μm to 1 mm.

Note 2 to entry: A precise border between visible radiation and infrared radiation cannot be defined because visual sensation at wavelengths greater than 780 nm can be experienced.

Note 3 to entry: In some applications the infrared spectrum has also been divided into "near", "middle", and "far" infrared; however, the borders necessarily vary with the application.

Note 4 to entry: This entry was numbered 845-01-04 in IEC 60050-845:1987.

Note 5 to entry: This entry was numbered 17-580 and 17-610 in CIE S 017:2011.

Publication date: 2020-12
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