Essay On Visible Radiation

Visible Light

Visible radiation (light) is the segment of the electromagnetic spectrum and consists of seven colors (red, orange, yellow, green, blue, indigo, violet). It has the ability to penetrate the skin to a depth of 1 cm but operates mainly through the visual analyzer - the retina. The perception of visible light and color of its constituent components have an indirect effect on the central nervous system and the mental state. Yellow, green and orange colors have a positive impact on person's mood, blue and purple - negative. It was found that the red and orange colors stimulate the activity of the cerebral cortex. These properties must be considered in light color interiors.

Visible radiation has a shorter wavelength than infrared. Therefore, its quants have higher energy. However, the skin is

The UV spectrum is divided on near (400-200 nm.) and vacuum (200-10 nm.) The UV radiation of the latter is strongly absorbed by air, and its research is only possible in a vacuum. The emission spectrum can be linear (isolated atoms, ions, molecules, light), continuous (recombination radiation or braking) or consist of the band (heavy molecules).

Ionization of atoms and the photoelectric effect can occur during the interaction of radiation with matter. Optical properties of the substances in the UV region of the spectrum significantly differs from the optical properties in the invisible area. Typically, reduction of transparency in UI ( an increase of the absorption coefficient) is typical for a matter that is transparent in the visible region. For example, the ordinary glass is non-transparent at 320 nm. At shorter wavelengths only uviol glass, sapphire, magnesium fluoride, quartz, fluorite, lithium fluoride (has the most distant border transparency - to 105 nm.) are transparent