Lähispektri

Lähispektri refers to the near-infrared region of the electromagnetic spectrum. This region spans wavelengths approximately from 700 nanometers to 2500 nanometers. It is located between visible light and the mid-infrared region. The term "lähispektri" is Finnish for "near spectrum."

The near-infrared spectrum is characterized by its ability to penetrate certain materials that are opaque to visible light, such as thin plastics, paper, and some soils. This property makes it useful in a variety of applications. For instance, in remote sensing, near-infrared wavelengths are used to study vegetation health and water content because plants reflect strongly in this region, and water absorbs it.

In industrial settings, near-infrared spectroscopy is employed for quality control and material analysis. It can identify and quantify different components in a sample based on their unique absorption patterns in the near-infrared. This is commonly used in the food industry, pharmaceuticals, and for polymer identification.

Furthermore, near-infrared light plays a role in astronomy, allowing scientists to observe objects that are obscured by dust clouds or to study the light from very distant, redshifted galaxies. It is also used in some forms of medical imaging and therapy. The energy levels associated with near-infrared photons are lower than those of visible light.