Road lights are illuminated on roads to provide necessa […]
Road lights are illuminated on roads to provide necessary visibility for vehicles and pedestrians at night. Road lamps generally need photosynthesis, the best light source has a long life, perennial use and maintenance-free. It has the characteristics of high light efficiency, good color rendering and instantaneous start-up under ultra-low temperature.
The road is the artery of the city. The main illumination is street lamp, which is set on the road to provide necessary visibility for vehicles and pedestrians at night. Road lights can improve traffic conditions, reduce driver fatigue, and help to improve road capacity and ensure traffic safety. Garden lamp, landscape lamp and street lamp form a three-dimensional lighting mode, enhance the effect of road decoration, beautify the city night scene, but also make up for the lack of illumination of road lamp.
Road lamps need photosynthesis, the best light source has a long life, perennial use and maintenance-free. It has the characteristics of high light efficiency, good color rendering and instantaneous start-up under ultra-low temperature. The common road lamps are incandescent lamp, high pressure mercury lamp, high pressure sodium lamp, low pressure sodium lamp, electrodeless lamp, metal halide lamp, fluorescent lamp, etc. At present, the mainstream product of road lighting source is still high-pressure sodium lamp. In recent years, the state strongly advocates energy saving and emission reduction. As a new type of light source, electrodeless lamp can make road surface achieve better uniformity than traditional light source.
Road lamps should use light energy reasonably to prevent glare. The light emitted should be illuminated along the required angle, and fall on the road surface to show the specified figure. The light distribution is uniform, the road surface brightness is large, and the glare is small. In order to reduce glare, light distribution can be controlled above the maximum light intensity. According to the form, width, vehicles and pedestrians of the road section, road lights can be arranged symmetrically on both sides of the road, staggered on both sides, on one side and suspended in the middle of the road. Generally speaking, roads with a width of more than 20 meters and greeting roads can be arranged symmetrically on both sides; roads with a width of more than 15 meters can be arranged staggered on both sides; narrower roads can be arranged on one side.
In special places such as road intersections, bends, ramps, railway crossings and pedestrian crossings, road lights are usually set up to facilitate drivers and pedestrians to identify road conditions. In the interior and exterior sections of the tunnel and the transitional sections from urban streets to suburban highways, the adaptability of the driver's eyes to the changes of light should be considered. The power, installation height and longitudinal distance of road lamp are important parameters of light distribution design. If these three factors are combined well, satisfactory lighting effect can be obtained.