Ballon Generali diameter of . It has been used as advertising billboard for Fortis, then from 2002 for Eutelsat. In 2008, a partnership has been signed with Banque populaire and Airparif : renamed "ballon Air de Paris", its internal illumination system changes the outer colour in real-time, according to the ambient air pollution in Paris, measured by Airparif : from green (good) to red (bad) through orange (poor). This system was completed by an independent lighting (panels light-emitting diode, visible especially at night on the lower part of the shell) stating the air quality near traffic with the same colour code. On
LED street light Such street lights can also cause glare for drivers and pedestrians. A drawback of LED focus panels is that most light is directed to the road, and less light to the footpaths and other areas. This can be addressed by the use of specialized lens design and adjustable mounting spigots. In performing a LED street lighting project, easy LED luminary models simplify the optimization for high-performance illumination designs. These practical equations may be used to optimize LED street lighting installations in order to minimize light pollution, increase comfort and visibility, and maximize both illumination uniformity and light utilization efficiency. The