Application of LEDs to traffic signal

The new traffic lights, you are seeing, are made out of arrays of light emitting diodes (LEDs). These are tiny, purely electronic lights that are extremely energy efficient and have a very long life. In this paper we present this new technology that is spreading further into niche solutions such as traffic signals. In particular we will focus on critical issues, due to the dependence of their opto-electronic characteristics by temperature that currently limit their use, defining a possible solution to this problem.