What light pollution is there in real life?

Black lights, rotating lights, fluorescent lights and flashing light sources installed in dance halls and nightclubs constitute color light pollution. According to the measurement, the intensity of ultraviolet rays produced by black light is much higher than that in sunlight, and the harmful effects on human body last for a long time. If people receive this radiation for a long time, they will cause nosebleeds, tooth loss, cataracts, even leukemia and other cancers.

The dazzling color light source is not only bad for the eyes, but also interferes with the central nervous system of the brain, making people dizzy, causing nausea, vomiting, insomnia and other symptoms. If people are exposed to colored lights for a long time, their psychological accumulation effect will also cause burnout, dizziness, neurasthenia and other physical and mental diseases to varying degrees.

2. Visual pollution

Refers to the chaotic visual environment in the urban environment. For example, there are messy wires, telephone lines, messy garbage, messy booths and colorful advertising posters on both sides of the city streets.

3. Mixed light

Different kinds of light sources mixed together will seriously affect passive recipients. And it may lead to a car accident. What is even more frightening is that for pilots flying at night, it takes energy to find and identify aviation signal lights in these various lights.

Step 4 glare

Light in the dark. Driving a high beam on a well-lit city street will temporarily "lose sight" of the opposite pedestrians or drivers, thus causing traffic accidents. And in the case of improper protection, this strong light will also hurt people's vision. With the rapid growth of the number of cars, a xenon lamp technology which can greatly improve the brightness of driving lighting is widely used in automobile lighting.

However, this advanced lighting technology has repeatedly become the murderer of road light pollution, causing hidden dangers to road traffic safety. At present, the national standard GB4599-94 "Light Distribution Performance of Automobile Headlights" has become invalid, and it has been replaced by GB 4599-2007 "Headlamps with filament bulbs for automobiles". It is required that the brightness of low beam and high beam should not be dazzling, but in actual operation, the standard of "not dazzling" is difficult to grasp.

5. Artificial sunlight

After nightfall, advertising lights and neon lights in shopping malls and hotels are dazzling. Some intense light beams even go straight into the sky, making night like day, which is called artificial day. In such a "city that never sleeps", the invasion of light causes too strong light sources to affect the daily rest of others, making it difficult to fall asleep at night, disturbing the normal biological clock of the human body and leading to low work efficiency during the day.

The sky is too bright to see the stars, which affects astronomical observation and aviation, and many observatories are forced to stop working. According to astronomical statistics, when the sky is not polluted by light at night, about 7000 stars can be seen, while in big cities where street lights, background lights and landscape lights are scattered randomly, only about 20~60 stars can be seen.

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