An LED street light (e40 led street light) is an integrated light that uses LEDs as its light source. These are considered integrated lights because, in most cases, the luminaireand the fixtureare not separate parts (except LEDGine-based luminaires). New in manufacturing, the LED light cluster is sealed on a panel and then assembled to the LED panel with a heat sinkto become an integrated lighting fixture.Different designs have been created that incorporate various types of LEDs into a light fixture. The current trend is to use high power 1 watt LEDs, but some companies use low power LEDs in their products, including several low power LEDs packed together to perform the same purpose as a single high power LED. The shape of theLED street light depends on several factors, including LED configuration, the heat sink used with the LEDs, and aesthetic design preference.Heat sinks for LED street lights are similar in design to heat sinks used to cool other electronics such as computers. Heat sinks tend to have as many grooves as possible to facilitate the flow of hot air away from the LEDs. The area of heat exchange will directly affect the lifespan of the LED street light.The lifespan of an LED street light is determined by its light output compared to its original design specification. Once its brightness decreases by 70 percent, an LED street light is considered to be at the end of its life.Most LED street lights have a lens on the LED panel, which is designed to cast its light in a rectangular pattern, an advantage compared to traditional street lights, which typically have a reflector on the back side of a high-pressure sodium lamp. In this case much of the luminance of the light is lost and produces light pollutionin the air and surrounding environment. 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 specialised lens design and adjustable mounting spigots.
