Rayleigh scattering is when light is scattered by small particles smaller than the wavelength of light. It occurs in gases, liquids, and solids and is used in optical fibers. The sky appears blue due to the scattering of blue light.
Rayleigh scattering is a physical phenomenon in which light is scattered in different directions by very small particles. These particles are much smaller than the wavelength of light involved and can even be as small as a single atom. Rayleigh scattering is most commonly observed in gases although it can occur in both liquids and solids. The amount of dispersion present depends on the polarizing properties of a particular type of particle and can vary depending on the elements involved.
The amount of dispersion depends on a number of factors. For the scattering to be known as Rayleigh scattering, the particle must be much smaller than the wavelength of light &mdahs; if the particle is close to the wavelength dimension then the approximations used for Rayleigh scattering are no longer correct. However, the larger the particle, the higher the scattering intensity, while the longer the wavelength, the lower the scattering intensity.
Light can be scattered by both atoms and molecules. When an atom or a single particle is involved, the small-size approximation can be used. This uses several assumptions, mainly that the particle is very small and that the particle’s radius and refractive index can be measured. A molecule often does not have such a clearly defined radius and therefore slightly different formulas must be used to calculate the intensity of the dispersion. In this case the polarizability – the amount by which the charge on the molecule will be affected by an electric field – is used to calculate the scattering intensity.
Rayleigh scattering is the mechanism that makes the sky blue. As sunlight travels through the atmosphere, it is scattered by the particles present. Some wavelengths of light, however, are scattered more than others. In this case, blue light is scattered more efficiently and the sky appears blue most of the time. The only exception is during sunset or sunrise, where the sun’s rays pass directly through the atmosphere. In this case, the sky appears redder because red light is not scattered as much as blue and can pass through the atmosphere unaffected.
There are also several practical applications of Rayleigh scattering used in modern technology. For example, the fact that light is scattered is used in some optical fibers. Some dispersion of optical signals is required for optical fibers to function properly and this is achieved by using small particles.
Protect your devices with Threat Protection by NordVPN
