If cloudless autumn day to look at the sky, the shining bright blue dome of the sky will not leave anyone indifferent.What explains such an amazing color?His reason is the three aspects - refraction, dispersion and polarization.In today's paper we discuss about what is the polarization of the light.
Light is one of the types of electromagnetic radiation, so is characterized by a source and direction.In addition, we should not forget about its dual nature: in one case it is, as already mentioned, is a wave, and the other - particles (photons).Polarization of light - is one of the properties of any radiation in the optical range.When the polarization fluctuations of the light beam of particles directed to a transverse surface, are carried out in one and the same plane.Other components are cut.
easiest example to understand what the polarization of light.Imagine a long rope, arranged horizontally between two points.The rope passes through the vertical slot in the plate-shield.If now with its one end to pick up and form a wave, then it reaches the opposite end only if the generated coaxially with the slit in the shield, i.e.vertically.When you try to move the rope horizontally (left and right) wave will be repaid as soon reached the shield, as it does not "squeeze" across the gap.In this example, the rope - is electromagnetic radiation shield - transparent (or translucent medium), and a slot - specific property protection.
Since light - is an electromagnetic wave, it depends on the electric and magnetic intensity vectors.They are always perpendicular to each other and, moreover, form a notional plane perpendicular to the line of propagation of the wave.Incidentally, the circular polarization of light occurs if the vectors of magnetic induction and electric field directions are rotated relative to the light beam.In turn, when vibrations of the electric field vector in the same plane of plane polarized electromagnetic wave occurs.Her second name, which reflects the same process - "linearly polarized".
Interestingly, the radiation of atoms of a single quantum of light is always polarized.At the same time, the light output bulb, sun, candles, flashlights and so on. Unpolarized.This is because the radiation is emitted from a plurality of atoms in which the polarization varies.Accordingly, the total flux loses focus.The polarization of the light to a great extent depends on the characteristics of the substance or the arrangement of atoms in its crystal lattice (for solids, such as transparent crystals).By the way, the first experiments were made with crystals and only later, scientists have paid attention to the gaseous environment (atmosphere).It is easy to understand that the polarization of the light is also dependent on the location of the observer (sensor, photocell, etc.).Thus, increasing the angle between the direction of the light source and a vector indicating the direction of the beam, the polarization increases.If the directions are parallel, under ideal conditions the polarization is absent.
There is also a third option - the flow of partially polarized light.This configuration occurs when the electric field is dominated by vibrations or magnetic induction (of vectors).
curious fact: the human eye easily discerns the wavelength (color aspect of the light) and intensity, but registration is available polarization indirectly.At the same time, many insects with faceted eyes perfectly distinguish the polarization of the wave.It is believed that this helps them to navigate.