Researchers from the Fraunhofer Institute for Industrial Engineering IAO in Stuttgart, Germany, in collaboration with the fixture manufacturer LEiDs GmbH (Backnang, Germany), have created 50 x 50-cm ceiling tiles using RGB and white LEDs that, when combined with diffusers, have the appearance of an outdoor sky with clouds slowly moving overhead. For more LED Display information, please visit http://www.qs-tech.com

LED-based ceiling tiles
Each tile contains a board with 288 RGB and white LEDs, which is mounted on the ceiling. A white diffuser film is attached 30 cm beneath the LEDs to ensure that the individual points of light are not perceived as such. “This diffuser film creates homogenous lighting that illuminates the room throughout,” said Matthias Bues, Head of the Department at the IAO. The combination of LEDs makes it possible to generate more than 16 million hues.
The main focus of the project was to simulate natural lighting conditions on a cloudy day. The results of a preliminary study indicate that users find dynamic lighting conditions to be extremely pleasant. For more LED Display information, please visit http://www.qs-tech.com

The study involved ten volunteers who carried out their daily work over the course of four days under different lighting conditions under a lighting surface measuring 30 x 60 cm. On the first day, the lighting remained static. Throughout the second day, it fluctuated gently, and on the third day the fluctuations were rapid. On the fourth day, the participants could choose which type of lighting they wanted, and 80% opted for the fast, dynamic lighting.

A prototype of the ceiling that contains a total of 34,560 LEDs spanning an area of 34 m2 has been developed. It can generate up to 3000 lux at full power, but 500-1000 lux has been determined to be a comfortable lighting level.