Background introduction of LED street lighting system
In order to meet the urban road lighting design standards, traditional street lights often use more than 200 watts of mercury-containing bulbs.By 2009, by contrast, the optical efficiency of light-emitting diodes (LEDs) in the market has exceeded 100lm/w.
This means that the use of LED as a light source of lights, the power consumption will be greatly reduced.Because of the long life of LED, mercury-free and energy-saving characteristics, the use of LED lighting as a light source to replace the traditional LPs (low pressure sodium lamp) or MH (metal halide lamp) is a good choice.At present, wholesale led street light fixtures have been tested in various countries all over the world.
To solve the problem of energy shortages and greenhouse gas emissions, led streetlights have been applied in a number of places, including some regional and urban governments in China, North America and Europe.
As a result of the market on the factory most of the LED is Lang Bo (lambertian distribution) distribution, the center of Light Strong, but also a symmetrical circular spot distribution, can not be directly used for road lighting.
In addition, the quality of optical design directly determines the efficiency of LED street lamps.Some led streetlights plus a poorly designed two-time lens, some of the light in the lens after multiple reflection loss or can not be matched to the effective area.
Some two lenses, although the shape and uniformity of the spot can be, but the light efficiency is reduced by half nearly.Also, the quality of optical design are also set the wholesale led streetlights have no glare, some poorly designed lenses, although also can produce a rectangular, evenly distributed spot, the distribution curve can also be a bat wing, but because of the failure to use the cut-off light design, resulting in the direction of the road 75~90 range of light or a lot of radiation, This will cause glare to distant vehicles or pedestrians.
Good optical design should make full use of LED light source area small this advantage, fully consider the utilization of light, all the light from the LED chip distribution to the road, to form a good uniformity, no glare, the light distribution curve is bat wing spot.