Standard light D65

Standard light is a type of light with certain spectral characteristics specified by Commission Internationale d`Eclairage( CIE) in several classes. There are classes A, B, C and D, which are used for specific applications.

Standard illuminant D represents the daylight spectrum and is therefore of particular interest for the printing industry and projection technology. Illuminant D65 derives its name from its color temperature of 6,504 Kelvin (K). D65, which is used in the chemical and pharmaceutical industries, in paint production, and in the ceramics, fabric, paper and automotive industries, is also to be used as a reference illuminant where D50 with a color temperature of 5,000 K or D70 with 7,000 K were previously used. The standard illuminant D65 has a high blue content with which fluorescent colors can be detected.

D65 is used as an evaluation light source. However, for this purpose, the evaluation area must be illuminated with a luminous intensity of 2,000 lux( lx). The spectral distribution of D65 light sources is specified in DIN 5033 and lies between wavelengths of 300 nm and 780 nm, thus between ultraviolet and red.