Solar diaphragms at IMA, by Nouvel [478]

Many years ago, in 1987, Jean Nouvel advanced to nowadays energetic demands designing a showy facade for the Arab World Institute (IMA) in Paris. He took Arabic lattices as a model and built a frame of diaphragms, as those in photography equipment. Diaphragms of different sizes are opened and closed by hydraulic engines. So the lattice changes from small perforations to notable holes.

All diaphragms are governed by a piston, forcing the rotation of stainless steel rings. This rotation move metallic shutters inwards. The system was operated from a single optical cell if I remember correctly.

Certainly the system is costly, complicated and poorly suitable to the diversity of the inner activities, but the effort is remarkable and the idea is very ingenious. The truth is that, apparently, the mechanisms stopped working years ago and today the opening of the diaphragms is immovable.

General view of the building: