Ultraviolet spectrum

Ultraviolet Spectrum

The Ultraviolet Spectrum is a portion of the electromagnetic spectrum that lies between the visible light spectrum and X-rays. The term "ultraviolet" means "beyond violet", referring to its position in the spectrum following violet light.

Characteristics

Ultraviolet light has shorter wavelengths than visible light, typically ranging from 10 nanometers (nm) to 400 nm. It is categorized into three main types: UVA, UVB, and UVC, each with different properties and effects.

UVA

UVA or long-wave light ranges from 315 to 400 nm. It is the least harmful and makes up the majority of the ultraviolet light reaching the Earth's surface. It can cause skin aging and DNA damage.

UVB

UVB or medium-wave light ranges from 280 to 315 nm. It is biologically active and can cause sunburn and DNA damage, leading to skin cancer.

UVC

UVC or short-wave light ranges from 100 to 280 nm. It is the most dangerous type of UV light but is completely absorbed by the Earth's atmosphere.

Applications

Ultraviolet light has various applications in science and industry. It is used in black lights, fluorescent lamps, and in the sterilization of medical equipment. In medicine, UV light is used in phototherapy to treat conditions like psoriasis and vitiligo.

Health Effects

Exposure to UV light can have both beneficial and harmful effects on health. It is essential for the production of vitamin D in the skin, but excessive exposure can lead to skin cancer, cataracts, and other health problems.

See Also

• Electromagnetic spectrum
• Visible spectrum
• Infrared spectrum
• X-ray spectrum