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You will find a number of terms which are perhaps unknown when you inform yourself about natural daylight. A number of these terms are briefly explained below.

Color Rendering Index (CRI): an internationally established value that specifies the the color spectrum of a light source is compared to natural daylight. Natural daylight is hereby on 100. Our True-Light full-spectrum lamps have a CRI of 96-98, currently the highest for a lamp.

Hertz: the unit of frequency. The hertz is used in periodic (repetitive) phenomena. 1 Hz is consistent with a period of 1 second. On the network  the voltage changes with a frequency of 50 times per second, or 50 Hertz. A traditional  armature  is  50 Hertz.

High frequency: a term used in electronics for voltages that at a high rate. A High frequency armature has an electronic ballast. This EB provides a steady light and saves 25 % energy!

Colour temperature: a unit by which the wavelength of the light is emitted. The colour temperature is usually expressed in Kelvin (K). The colour temperature of natural light, just like our True-Light full-spectrum lamps, is 5,500 Kelvin.  When the colour temperature is below 5,500 Kelvin, the  colour shows as more yellow or pink. If the colour temperature is above 5,500 Kelvin, is shows as a more blue colour.

Luminous flux: a unit for the amount of light that a light source radiates in all directions per second.

Lumen: a unit for the light intensity of a light source. Lumen is  measured from the light source. The luminous flux in lumen is equal to the product of the size of the light source in candelas multiplied by the size of the solid angle in steradian.

Lux: a unit for the light intensity of a light source on a surface.  One lux is the light intensity produced  at a distance of 1 metre from the source.

Source: wikipedia