Translation of the Fact Sheet: ‘Virtual Sky is a dynamic, multi-spectral light ceiling. The prototype in the laboratory of the Fraunhofer IAO covers an area of 34 m² and integrated a total of 34,560 LED with four different colours. Like this more than 16 million colours can be represented. They are grouped in a total of 240 (20×12) individually controllable squares (30 x 30 cm) that can be directed just like display pixels. Both temporally and spatially dynamic lighting is possible.
The diffuse illumination of VirtualSky is complemented by a total of 350 warm white LED with focusing optics for targeted direct lighting. The picture shows the spectra that arises with the white LED, RGB LED, and the combination of both at full power. At full power illuminance of about 3000 Lux can be achieved. The spectra can also be adjusted to be very close to the daylight spectrum. For example: with a colour temperature of 5600 K a colour rendering index of Ra > 95th can be reached. The colour temperature can be infinitely set to a range between 1500 K to 27 000 K. The dynamic control (max. 30 Hz) allows to project videos of passing clouds or simulate a sunrise in the Aegean.
In addition it is possible to adjust the light control adaptively, individually and interactively according to the user. That individual cells can be illuminated in such way that the light follows the user when changing his location.
The maximum in the blue areas of the spectrum with the RGB LED lies at 462 nanometers, with the white LED at 448 nanometers. The intelligent control system allows a more or less strong circadian efficacy with constant colour temperature.
VirtualSky and its various influences of artificial light can be examined to humans. From the research results recommendations for a healthy lighting and optimal working conditions can be derived.’