VELUX Photometer
How much daylight does a VELUX Sun tunnel provide? This knowledge is essential for both the development of the VELUX Sun tunnel and as information to our customers about the daylight performance of the VELUX Sun tunnel. In cooperation with photometric experts, VELUX has established a unique photometric test system – the VELUX Photometer.
The Photometer measures not only the amount of light transmitted through the sun tunnel, but also how the light is distributed inside a room. Both the amount and the distribution of light are important parameters for the experience of natural daylight in a room.
The daylight performance of VELUX Sun tunnel has been reproduced in the VELUX Photometer under various daylight conditions ranging from an overcast sky to a clear, sunny sky. The measuring principle of VELUX Photometer is shown in cross-sectional view below.