Road lighting refers to the installation of luminaires on the road to provide the necessary visibility for vehicles and pedestrians at night. Road lighting can not only improve traffic conditions and reduce driver fatigue, but also help improve road capacity and ensure traffic safety. Lighting lamps for traditional road lighting include high pressure sodium lamps and electrodeless lamps.

At present, most of the lamps used in road lighting are LED street lamps. In fact, LED street lamps are currently combined with intelligent LED street lamp control systems. Lighting fixtures should use light energy reasonably to prevent glare. The light emitted by the LED street light should be irradiated at the required angle and fall on the road in a designated pattern. The light distribution of the lamp is uniform, which can make the road surface brighter and less glare. To reduce glare, different light distribution methods can be used to control above the maximum light intensity.

Street light can be roughly divided into light-cutting light, semi-cutting light and non-cutting light.

1. The light irradiated by the light-cutting light outside the road width does not exceed 10% of the rated lumens of the light source. The light is distributed along the road and produces little glare. It is suitable for main streets, arterial roads and expressways. The angle between the maximum light intensity direction of the luminaire and the downward vertical axis of the luminaire is 0°~65°, and the maximum allowable values ​​of light intensity in the 90° angle and 80° angle directions are 10cd/1000lm and 30cd/1000lm respectively. When the luminous flux of the light source is not considered, the maximum value of its luminous intensity in the 90° angle direction shall not exceed 1000cd.

2. The light irradiated outside the road width by the half-cut light fixture does not exceed 30% of the rated lumens of the light source, and the light is distributed along the road, which is suitable for general-grade streets. The angle between the maximum light intensity direction of the luminaire and the downward vertical axis of the luminaire is 0°~75°, and the maximum allowable light intensity values ​​in the 90° angle and 80° angle directions are 50cd/1000lm and 100cd/1000lm respectively. When the luminous flux of the light source is not considered, the maximum value of its light intensity in the 90° angle direction shall not exceed 1000cd.

3. The non-cutting lamps do not limit the luminous flux above the maximum light intensity of the lamps, and the glare value is large. It is only suitable for streets with bright surrounding environment or secondary streets with little traffic. The range of the luminaire is determined by the elevation angle of the beam. The maximum light intensity direction of the lamp is not limited, and the maximum light intensity in the 90° angle direction shall not exceed 1000cd.