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 note applies to the French language only.