Mercedes-Benz tests switchable transparency roof for new SLK

                                 Roof in darkened mode

                                      Roof in transparent mode

Mercedes-Benz will introduce a new breed of "switchable" glass roof as an optional extra on the new SLK next year. The panoramic vario-roof with MAGIC SKY CONTROL can – aside from being quite a mouthful – either be darkened or made transparent at the touch of a button.
Based on the physics of a plate condenser, when the glass structure of the roof is subjected to an electric voltage, particles in the structure position themselves so that light is able to pass through. If there is no voltage the particles position themselves randomly, darkening the glass and partially blocking the light. This allows the transparency of the glass to be altered at the touch of a button located in the vehicle’s overhead console which controls a converter integrated into the front section of the roof.
But Mercedes says passengers won’t be the only ones to benefit from the technology. The switchable glass roof should also take some of the strain of the air-conditioning system, thereby cutting CO2 emissions.