Actinic rays

Actinic rays are a form of electromagnetic radiation that has the ability to cause photochemical reaction. These rays are primarily found in the ultraviolet portion of the electromagnetic spectrum, but can also be present in the visible and infrared regions. Actinic rays are responsible for a variety of natural phenomena, including the photosynthesis in plants and the production of vitamin D in the human body.

History

The term "actinic rays" was first used in the 19th century by John Herschel, a British scientist who was studying the effects of different types of light on photographic plates. He noticed that certain types of light, which he called "actinic rays", were able to cause a chemical reaction on the plates, resulting in a visible image.

Properties

Actinic rays are characterized by their ability to cause photochemical reactions. This means that they have enough energy to break chemical bonds and cause new ones to form. This property is what allows actinic rays to play a crucial role in processes such as photosynthesis and vitamin D production.

In the ultraviolet region of the spectrum, actinic rays can be further divided into three types: UVA, UVB, and UVC. UVA rays are the least energetic and are responsible for tanning in the human skin. UVB rays are more energetic and can cause sunburn. UVC rays are the most energetic and are capable of causing severe damage to living tissues. However, most UVC rays are absorbed by the Earth's atmosphere and do not reach the surface.

Applications

Actinic rays have a wide range of applications in various fields. In medicine, they are used in phototherapy to treat conditions such as psoriasis and jaundice. In industry, they are used in the curing of inks and resins. In environmental science, they are used in the study of climate change, as changes in the amount of actinic rays reaching the Earth's surface can have significant effects on the climate.

Health effects

While actinic rays are necessary for certain biological processes, excessive exposure can have harmful effects. Overexposure to UVB rays can lead to sunburn and increase the risk of skin cancer. UVC rays, while mostly absorbed by the atmosphere, can be produced by artificial sources and can cause severe burns and eye injuries.

See also

• Electromagnetic spectrum
• Ultraviolet
• Photosynthesis
• Phototherapy