What is polarized light & plane polarized light?

Question

Plz explain in a way comprehendable by a student who has never gone through a rigorous definition of the same. I've gone through some Organic Chemistry books (& some Physics books too), but they are not at all satisfactory to even understand the basic concepts associated. I've also searched in some search engines, but to no avail - they are either wayward, or of a much higher level, not discussing about the basics involved. Also, is there any other form of polarized light? Plz explain. Thanks!

Answer 1

You have probably heard that light consists of electromagnetic waves. The changing electrostatic field generates a changing magnetic field, which in turn regenerates the electrostatic field. The key notion here is that both fields are perpendicular to the direction of propagation -- and to each other. Light from most sources, such as an incandescent light bulb, is unpolarized: the individual photons can have any orientation of the electric and magnetic fields. But there are substances, such as films containing long needle-shaped crystals, which filter light so that only light with an e-field perpendicular to the crystals can pass. So all the photons passing through such a substance have their e-field in the same direction, and if you intercept the beam with another polarizer, with the crystals at right angle to those in the first one, the photons will be blocked and no light can pass. In most cases, polarized light implies plane polarized light -- the e-fields all lie in one plane.
There is also something called circularly polarized light. It can be made from plane polarized light using a gadget called a quarter-wave plate -- which pases light of all polarization, but retards light in one particular plane of polarization by a quarter of a wavelength with respect to light polarized at right angles. It is beyond the depth to which I wish to get to go into the gory details; it will suffice that you have heard the terms and know that they exist.

Answer 2

Plane Polarized Light

Answer 3

Plane Polarised Light

Answer 4

This Site Might Help You.

RE:
What is polarized light & plane polarized light?
Plz explain in a way comprehendable by a student who has never gone through a rigorous definition of the same. I've gone through some Organic Chemistry books (& some Physics books too), but they are not at all satisfactory to even understand the basic concepts associated. I've also searched...

Answer 5

LASERS Light Amplified Stimulation Emission Radiation. Lasers / diodes emit polarized light. each of the same wavelength and thus travels in straight lines, only their application is limited to lab use and small applications. That due to atmospherics, both the crap in the air causing the beams to bend and to dissipate heat along its path. Red Lasers are common, the new blue lasers are a shorter wavelength and that makes for more data to be squashed into these new Cd-Roms, something like 40Gigz now. In eye surgery the use of laser diodes can pinpoint a single vein without damaging the surrounding arias, though this application uses pulsed lasers to control the exposure and heat transfer problems. Polarized lenses prevent or limit light to make contact with the eye by polarizing and only allowing vision of those filtered light-waves, ouch! Though light don't travel in waves, it once where believed so.

Answer 6

Polarized light waves are light waves in which the vibrations occur in a single plane. The process of transforming unpolarized light into polarized light is known as polarization. There are a variety of methods of polarizing light. The four methods are :

Polarization by Transmission
Polarization by Reflection
Polarization by Refraction
Polarization by Scattering
Light consists of oscillating electrical fields, denoted by E, and magnetic fields, denoted by B. We will concentrate on the electric field component and ignore the magnetic field; however, we could just as well describe light and its effects in terms of the magnetic field component. We don't do it because the interaction of magnetic fields with charged particles is more complex than electric fields, but we could.

Light whose electric field oscillates in a particular way is said to be polarized. If the oscillation is in a plane, the light is said to be plane polarized (top right). Plane polarized light can be polarized in different directions. Light can also be circularly polarized, with its electric field direction spiraling in a screw pattern. Circularly polarized light can be right- or left-handed (bottom). Light can consist of a combination of plane and circular polarization as well; its electric field spirals in a screw fashion with an elliptical cross-section. Such light is called elliptically polarized.

Although we often speak of "unpolarized" light, every photon of light is polarized in some manner. "Unpolarized" light is a random mixture of light of all polarizations. When light has an easily observed dominant polarization, we refer to it as polarized

Answer 7

Here's a really poor analogy to help explain this, but here goes my vending machine example:

Think of incoherent radiation; EM radiation that has random directions; intensities; and energy, as all the possible "1.00" units in the world: Yen, pound, peso, dollar, you name it. The vending machine you approach says "$1.00". The mere act of the $ plus how much it wants can be considered as a form of polarization; the "$1.00" tells you "It wants the American Dollar and only wants one of them." Plane polarization is a way to polarize light or "Which way will you use to make $1.00"?

I know this probably didn't help you one damn bit, but at least I tried.

Answer 8

Polarization

A light wave is an electromagnetic wave which travels through the vacuum of outer space. Light waves are produced by vibrating electric charges. The nature of such electromagnetic waves is beyond the scope of The Physics Classroom Tutorial. For our purposes, it is sufficient to merely say that an electromagnetic wave is a transverse wave which has both an electric and a magnetic component.

The transverse nature of an electromagnetic wave is quite different from any other type of wave which has been discussed in The Physics Classroom Tutorial. Let's suppose that we use the customary slinky to model the behavior of an electromagnetic wave. As an electromagnetic wave traveled towards you, then you would observe the vibrations of the slinky occurring in more than one plane of vibration. This is quite different than what you might notice if you were to look along a slinky and observe a slinky wave traveling towards you. Indeed, the coils of the slinky would be vibrating back and forth as the slinky approached; yet these vibrations would occur in a single plane of space. That is, the coils of the slinky might vibrate up and down or left and right. Yet regardless of their direction of vibration, they would be moving along the same linear direction as you sighted along the slinky. If a slinky wave were an electromagnetic wave, then the vibrations of the slinky would occur in multiple planes. Unlike a usual slinky wave, the electric and magnetic vibrations of an electromagnetic wave occur in numerous planes. A light wave which is vibrating in more than one plane is referred to as unpolarized light. Light emitted by the sun, by a lamp in the classroom, or by a candle flame is unpolarized light. Such light waves are created by electric charges which vibrate in a variety of directions, thus creating an electromagnetic wave which vibrates in a variety of directions. This concept of unpolarized light is rather difficult to visualize. In general, it is helpful to picture unpolarized light as a wave which has an average of half its vibrations in a horizontal plane and half of its vibrations in a vertical plane.

It is possible to transform unpolarized light into polarized light. Polarized light waves are light waves in which the vibrations occur in a single plane. The process of transforming unpolarized light into polarized light is known as polarization. There are a variety of methods of polarizing light. The four methods discussed on this page are :

* Polarization by Transmission
* Polarization by Reflection
* Polarization by Refraction
* Polarization by Scattering


Basics – plane waves

The simplest manifestation of polarization to visualize is that of a plane wave, which is a good approximation of most light waves (a plane wave is a wave with infinitely long and wide wavefronts). All electromagnetic waves propagating in free space or in a uniform material of infinite extent have electric and magnetic fields perpendicular to the direction of propagation. Conventionally, when considering polarization, the electric field vector is described and the magnetic field is ignored since it is perpendicular to the electric field and proportional to it. The electric field vector may be arbitrarily divided into two perpendicular components labelled x and y (with z indicating the direction of travel). For a simple harmonic wave, where the amplitude of the electric vector varies in a sinusoidal manner, the two components have exactly the same frequency. However, these components have two other defining characteristics that can differ. First, the two components may not have the same amplitude. Second, the two components may not have the same phase, that is they may not reach their maxima and minima at the same time. The shape traced out in a fixed plane by the electric vector as such a plane wave passes over it (a Lissajous figure), is a description of the polarization state. The following figures show some examples of the evolution of the electric field vector (blue) with time (the vertical axes), along with its x and y components (red/left and green/right), and the path traced by the tip of the vector in the plane (purple):
Linear polarization diagram
Linear
Circular polarization diagram
Circular
Elliptical polarization diagram
Elliptical


In the figure on the left, the two orthogonal (perpendicular) components are in phase. In this case the ratio of the strengths of the two components is constant, so the direction of the electric vector (the vector sum of these two components) is constant. Since the tip of the vector traces out a single line in the plane, this special case is called linear polarization. The direction of this line depends on the relative amplitudes of the two components.

In the middle figure above, the two orthogonal components have exactly the same amplitude and are exactly ninety degrees out of phase. In this case one component is zero when the other component is at maximum or minimum amplitude. There are two possible phase relationships that satisfy this requirement: the x component can be ninety degrees ahead of the y component or it can be ninety degrees behind the y component. In this special case the electric vector traces out a circle in the plane, so this special case is called circular polarization. The direction the field rotates in depends on which of the two phase relationships exists. These cases are called right-hand circular polarization and left-hand circular polarization, depending on which way the electric vector rotates.

All other cases, that is where the two components are not in phase and either do not have the same amplitude and/or are not ninety degrees out of phase are called elliptical polarization because the electric vector traces out an ellipse in the plane (the polarization ellipse).

The "cartesian" decomposition of the electric field into x and y components is, of course, arbitrary. Plane waves of any polarization can be described instead by combining waves of opposite circular polarization, for example. The cartesian polarization decomposition is natural when dealing with reflection from surfaces, birefringent materials, or synchrotron radiation. The circularly polarized modes are a more useful basis for the study of light propagation in stereoisomers.

Answer 9

You can discuss the science related problem at www.sciforum.indianscience.in and already some explanation about ur this question is available at research topic and subject discussion board.

All the Best.

Answer 10

polrised light is light .
the light is passing trough NICKAL prosam The light direction is changes with two ways...one is light direction another one is pependicular.
so polarise light contains two directions.
Non polarised light only one direction...........