The Tvilight system works by sensing someone on the street—whether it’s a car, cyclist, or pedestrian—and instantly gets brighter in exactly the right place, while other lights stay on at a dim level. It’s quite a bit more complicated than the typical motion sensor lights you might see inside an office. Instead of just one light, the system illuminates multiple lights all around a moving vehicle or pedestrian.
“When I was flying, I was amazed to see how many streetlights are burning all night even when there’s no one around.”
Chintan Shah,CEO
The sensors inside are also smart enough to know not to activate the lights when a bird flies by, or when wind moves tree branches. The system can even tell what type of object is approaching; since a car moves faster, the lights around it are a bigger diameter and start brightening farther down the block.
By Adele peters
First published on September 1, 2014
From: http://www.fastcoexist.com/3024383/these-smart-streetlights-only-get-bright-when-theyre-needed