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The luminous flux is the light output of the light source. The unit of measurement is lumens (lm).


The light intensity indicates the luminous flux related to the solid angle. The unit of measure is Candela (cd).


Illuminance E describes the area-related luminous flux that strikes an illuminated object. The unit of measure is lux (lx).


Luminance L provides detailed information about the location and direction dependence of the luminous flux emitted by a light source.

Over 80% of the day we are exposed to artificial light

If we look at the workplace guidelines, e.g. for office workplaces, 500 lux are required, this corresponds to the state ...

... of permanent dusk

This makes the quality of artificial light so enormously important.

Good lighting has a new dimension

It also takes into account the biological effectiveness of light, also called Human Centric Light HCL.

The light intensity varies from several 1000 lux in a cloudy afternoon sky ...

... up to over 100,000 lux on a cloudy summer day