Will the light make people tan? Which light is better?

There are lights everywhere. Without them, people can’t see. Will lights make people tanned? Which lamp is better?

Will the light make you tan?

Ordinary fluorescent lamps will not make people tan. Fluorescent lamps are excited by ultraviolet rays, but the ultraviolet rays are inside the glass tube. When the light passes through the glass, the ultraviolet rays that are harmful to the human body have been absorbed. In case a small amount is not absorbed, it will disappear as long as it is away from the lamp (the intensity is inversely proportional to the square of the distance, plus the absorption by the air). Moreover, the energy of the ultraviolet rays emitted by fluorescent lamps is so weak compared to the ultraviolet rays emitted by sunlight that it is almost negligible and does not need to be considered at all. The power of fluorescent lamps is not high, and the ultraviolet rays in the lamp tube are absorbed by the fluorescent powder and converted into white light for lighting, which has no major impact on the skin.

Which lamp is better?

1. Incandescent lamp

Also called an electric light bulb, its working principle is that when current passes through the filament (tungsten filament, with a melting point of over 3000 degrees Celsius), heat is generated. The spiral filament continuously accumulates heat, causing the temperature of the filament to reach over 2000 degrees Celsius. The hotter the filament, the brighter the light it emits. That’s why it’s called an incandescent lamp. Advantages: small light source, with a wide variety of lampshades; highly versatile, with many colors, and with directional, scattering, diffuse and other forms; can be used to enhance the three-dimensional sense of objects, and the color of incandescent lamps is closest to the color of sunlight.

2. Fluorescent lamp

Also called fluorescent lamp, the gas contained in the fluorescent tube is argon (also contains neon or krypton) and a few drops of mercury. Mercury atoms in the lamp tube release ultraviolet light through the process of gas discharge, and the fluorescent material on the inner surface of the lamp tube absorbs the ultraviolet light and releases visible light. Different fluorescent substances emit different visible lights.

Advantages: Energy saving, about 60% of the electricity consumed by fluorescent lamps can be converted into ultraviolet light, and the rest of the energy is converted into heat energy. Generally, the efficiency of converting ultraviolet light into visible light is about 40%. Therefore, the efficiency of fluorescent lamps is about 60%×40%=24%, which is about twice that of tungsten filament lamps of the same power.

3. Energy-saving lamps

Also called compact fluorescent lamp, the light-emitting principle is not much different from that of fluorescent lamp. However, energy-saving lamps are relatively small in size and use smaller electronic ballasts, which reduces the flicker phenomenon. Advantages: High luminous efficiency, more than 5 times that of ordinary incandescent lamps, obvious energy-saving effect; long life, about 8 times that of ordinary bulbs; small size and easy to use.

Ordinary lighting will not make people tan, you have to choose the right light.