Choosing the right LED color for traffic lights requires comprehensive consideration of many factors. Here are some key points: Follow traffic rules and standards According to international practice and my country's traffic regulations, the colors of traffic lights are usually red, yellow and green. Red means no passage, yellow means warning preparation, and green means passage is allowed. This is the basic basis for selecting the color of the lamp beads and cannot be changed at will. Consider the optical properties of the color Red: The wavelength of red light is longer and has strong penetrating ability in the air. Even in severe weather conditions, such as fog and heavy rain, it can be transmitted over a long distance and is easily noticed by drivers and pedestrians. Therefore, it is a traffic signal. The ideal color for a light that indicates that traffic is prohibited. Green: Green light is relatively soft, and the human eye is more sensitive to green light. In addition, green is more coordinated with the color of the natural environment, giving people a sense of comfort and safety, making it suitable as a signal color for allowing traffic. Yellow:

The wavelength of yellow light is moderate, and its warning effect is obvious. It can play a good transition role between red and green, reminding drivers and pedestrians that the traffic signal is about to change. Combined with the actual use environment weather conditions: In areas with low visibility such as foggy and rainy areas, red and yellow lamp beads with strong penetration should be given priority to ensure that the signal can still be clearly seen in bad weather. For areas with more sunny days and good visibility, the brightness and visual effect of green lamp beads can also be better guaranteed. Background light interference: If the traffic light is installed in a place with complex ambient light, such as a busy commercial area, a street with more neon lights, etc., it is necessary to select lamp beads with high color contrast and sufficient brightness to highlight the traffic signal and avoid being drowned by background light. For example, in this case, the red lamp beads have a greater contrast with the surrounding environment and are easier to be identified. Meet the requirements of brightness and viewing angle Brightness: Traffic lights need to be clearly visible at different distances and lighting conditions, so the brightness of the lamp beads must be high enough. Generally speaking, places with large traffic volume and high speed such as main roads require lamp beads with higher brightness; while in some branch roads or places with more pedestrians, the brightness requirements can be relatively lower, but the signal must also be clearly visible. Viewing angle: The viewing angle of the traffic light should be able to cover the entire intersection or the area that needs to be indicated, ensuring that drivers and pedestrians in all directions can see the signal. Different types of lamp beads have different viewing angles. The viewing angle of the direct-insert lamp beads is relatively narrow, but the focusing property is good, which is suitable for long-distance indication; the viewing angle of the patch lamp beads is wider, and the light distribution is uniform, which is suitable for traffic lights at close distances or requiring large-area lighting.

Ensure color consistency and stability Color consistency: The color of the lamp beads in the same group of traffic lights should be highly consistent to avoid excessive color differences that affect the accurate judgment of drivers and pedestrians on the signal. When choosing lamp beads, pay attention to the color consistency parameters and try to choose products with small color deviation. Stability: Traffic lights need to work stably for a long time, and the color of the lamp beads cannot change significantly over time or with factors such as ambient temperature. Therefore, it is necessary to choose light-emitting diodes with reliable quality and good stability to ensure the accuracy and reliability of traffic signals.