Ultraviolettvalgust

Ultraviolettvalgust, also known as ultraviolet (UV) light, is a form of electromagnetic radiation with wavelengths shorter than visible light but longer than X-rays. It typically ranges from about 10 nanometers to 400 nanometers in wavelength. UV light is invisible to the human eye and is categorized into three types based on wavelength: UVA (315–400 nm), UVB (280–315 nm), and UVC (100–280 nm).

UVA has the longest wavelength and penetrates deeply into the skin, contributing to skin aging and skin cancer. UVB has a shorter wavelength and is primarily responsible for sunburn and direct DNA damage, which can lead to skin cancer. UVC has the shortest wavelength and is highly germicidal; however, it is mostly absorbed by the Earth's ozone layer and does not reach ground level under normal conditions.

Ultraviolet light is naturally emitted by the sun and has various applications in science, industry, and medicine. It is used in sterilization and disinfection processes because of its ability to destroy bacteria and viruses. UV light also plays a role in fluorescence, curing of plastics, and in some medical treatments. In environmental science, UV radiation influences the Earth's atmosphere and plays a part in the formation and breakdown of ozone.

Exposure to UV radiation can be harmful to living organisms, leading to skin damage, eye injuries, and increased risk of cancer. As a result, sun protection measures such as clothing, sunscreen, and sunglasses are recommended when spending extended periods outdoors. The study of UV light continues to evolve, with ongoing research into its biological effects and technological applications.