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Coelux is a lighting systems that reproduce the true effect of natural sunlight entering through the opening in the integrated ceiling, with a realistic sun perceived at infinite distance surrounded by a clear deep blue sky.
It’s a beautiful and genius Italian invention made by the Prof. Paolo Di Trapani, of Insubria University in Como. Coelux brings the sun in every space experiencing the sky. 
People really believe that it’s a real window, when they understand they experiment is astonishment! After more than 10 years of studies Prof. Di Trapani succeed recreating in few millimeters what happen to the sunrays in the atmosphere, the “Rayleigh scattering”.
The products faithfully mimic natural sunlight, a clear blue sky and its infinite depth. One distinct “sun” bursts down into the scene through the opening, either on the ceiling or on the wall.
I saw CoeLux during the last Fuorisalone, at Palazzo Clerici, it was quite a shock find out what they were able to recreate! Their mission is to foster an innovative solution for lighting, architecture and real-estate industries aiming at creating the perception of an extraordinarily wide space, by means of a genuine physical reproduction of optical atmospheric phenomena indoors. Think what it can do in healthcare structures (it’s already used at Humanitas Hospital in Rozzano), hospitality and recreation areas, public spaces, school, offices, place where there are just few hours of light… The sun has a huge healthy effects on human beings.
Who would choose a cloudy sky when you can have bright sun every day?
Enjoy!