The blue color of a luminous lamp means that the color temperature of the light source changes from yellow or white to a light wavelength closer to blue. This change may be caused by human factors, such as using different kinds of light bulbs or adjusting the color of lights. It may also be caused by natural factors, such as rain and smog at night, which will make the original yellow light appear bluer through fog and rain.

The blue color of night light has a certain influence on human beings. Because the brightness perception of human eyes is sensitive to light with different colors and wavelengths, we will feel different when the color of light changes. For people who are sensitive to eye health, such as the elderly and children, this change may cause discomfort and even affect the quality of sleep.

The blue color of the luminous lamp also has a certain impact on the environment. The phenomenon of "light pollution" that often occurs in modern cities, that is, excessive lighting at night makes it difficult to see the starry sky and sky, has attracted more and more attention. The blue color of luminous lamp is also a manifestation of light pollution, which will have a certain impact on the ecological environment and the law of day and night of animals. Therefore, it is one of the important guarantees to maintain ecological balance and human health to reasonably adjust the color and intensity of lights and reduce light pollution at night.