As night falls, the city becomes ablaze with lights, and the roads are adorned with street lamps that cast an exceptionally bright glow. Observant friends may notice that the light emitted by street lamps is mostly warm yellow, rather than the white light emitted by the lamps installed in our homes. So why is the light emitted by street lamps yellow instead of white? In fact, this is related to the color, wavelength, and illumination effect of light. Next, let me guide you to understand why the light emitted by street lamps is yellow.
Street lights are not only required to provide clear visibility of the road surface at night, but also need strong penetrating power. Otherwise, they cannot effectively illuminate the road in foggy weather, thus losing their function and potentially causing traffic accidents. Therefore, when choosing street lights, people generally opt for high-pressure sodium lamps.
There is another more important reason, that is, high-pressure sodium lamps are the most energy-efficient among traditional lighting sources. Since the electricity bill and maintenance of street lamps are fiscal expenditures, considering economic practicality, it is necessary to achieve the best results with the least amount of money.