Less expensive - Several miles of optical cable can be made cheaper than equivalent lengths of copper wire. This saves your provider (cable TV, Internet) and you money. Thinner - Optical fibers can be drawn to smaller diameters than copper wire. Higher carrying capacity - Because optical fibers are thinner than copper wires, more fibers can be bundled into a given-diameter cable than copper wires. This allows more phone lines to go over the same cable or more channels to come through the cable into your cable TV box. Less signal degradation - The loss of signal in optical fiber is less than in copper wire. Light signals - Unlike electrical signals in copper wires, light signals from one fiber do not interfere with those of other fibers in the same cable. This means clearer phone conversations or TV reception. Low power - Because signals in optical fibers degrade less, lower-power transmitters can be used instead of the high-voltage electrical transmitters needed for copper wires. Again, this saves your provider and you money. Digital signals - Optical fibers are ideally suited for carrying digital information, which is especially useful in computer networks. Non-flammable - Because no electricity is passed through optical fibers, there is no fire hazard. Lightweight - An optical cable weighs less than a comparable copper wire cable. Fiber-optic cables take up less space in the ground. Flexible - Because fiber optics are so flexible and can transmit and receive light, they are used in many flexible digital cameras for the following purposes:

• Medical imaging - in bronchoscopes, endoscopes, laparoscopes
• Mechanical imaging - inspecting mechanical welds in pipes and engines (in airplanes, rockets, space shuttles, cars)
• Plumbing - to inspect sewer lines

Because of these advantages, you see fiber optics in many industries, most notably telecommunications and computer networks. For example, if you telephone Europe from the United States (or vice versa) and the signal is bounced off a communications satellite, you often hear an echo on the line. But with transatlantic fiber-optic cables, you have a direct connection with no echoes.

A good example of polarized light is polarized sunglasses. when you look at something head on the glasses work light regular sunglasses. However if you angle them, the sun goes right through.

Another Answer

The polarization of light refers to the plane the electric field of its electromagnetic wave is oriented. Sunlight is comprised light waves polarized in all orientations.

Polarized sunglasses allow only one orientation of light to pass through their lenses, thus limiting the amount of light that passes through them.

LCD displays use the polarization of light to display their segments, or actually block light from passing through their segments. They work because the bottom layer (layer 1) of a passive display is reflective, layer 2 is a vertically polarized filter, layer 3 is a common electrode with vertical ridges, layer 4 is the liquid crystals, layer 5 is the shaped electrodes on a sheet with horizontal ridges, and the top layer (layer 6) is a horizontally polarized filter. The bottoms of layer 4's liquid crystal molecules align themselves with the vertically aligned ridges in layer 3. The tops of layer 4's liquid crystal molecules align themselves with the horizontally aligned ridges in layer 5. The liquid crystal molecules in between are helically oriented, or twisted. At rest, only the horizontally polarized part of the ambient light passes through layers 6 and 5 (this is why passive LCD displays look grey). Its polarization then follows the twist in the liquid crystal chain to end up oriented vertically. It then passes through layer 2 and is reflected off layer 1, and its travel reverses back out of the display. When an electric charge is applied to a segment, the liquid crystals between the electrodes untwist blocking the light path for that segment, which makes that segment appear dark.

Optics is the branch of physics which involves the behavior and properties of light, including its interactions with matter and the construction of instruments that use or detect it.[1] Optics usually describes the behavior of visible, ultraviolet, and infrared light. Because light is an electromagnetic wave, other forms of electromagnetic radiation such as X-rays, microwaves, and radio waves exhibit similar properties.[1]

Most optical phenomena can be accounted for using the classical electromagnetic description of light. Complete electromagnetic descriptions of light are, however, often difficult to apply in practice. Practical optics is usually done using simplified models. The most common of these, geometric optics, treats light as a collection of rays that travel in straight lines and bend when they pass through or reflect from surfaces. Physical optics is a more comprehensive model of light, which includes wave effects such as diffraction and interference that cannot be accounted for in geometric optics. Historically, the ray-based model of light was developed first, followed by the wave model of light. Progress in electromagnetic theory in the 19th century led to the discovery that light waves were in fact electromagnetic radiation.

Some phenomena depend on the fact that light has both wave-like and particle-like properties. Explanation of these effects requires quantum mechanics. When considering light's particle-like properties, the light is modeled as a collection of particles called "photons". Quantum optics deals with the application of quantum mechanics to optical systems.

Optical science is relevant to and studied in many related disciplines including astronomy, various engineering fields, photography, and medicine (particularly ophthalmology and optometry). Practical applications of optics are found in a variety of technologies and everyday objects, including mirrors, lenses, telescopes, microscopes, lasers, and fiber optics.

Perhaps you wish to know how they reflect or why some surfaces reflect whereas others don't.

There are basically three types of surfaces: those that absorb light, those that reflect it, and those that neither reflect it nor absorb it. Not counting "black holes," there are no objects that absorb all light perfectly or reflect all light perfectly or pass light perfectly. All objects reflect and absorb light to some degree. Some reflect more than absorb, some absorb more than reflect, and some -- like windows -- let light pass right through them. Mirrors are highly reflective, whereas black cotton or wool fabric doesn't reflect much at all.

So, let's take a look at stuff that reflects. A mirror reflects, but so does a piece of loose-leaf paper. If the paper did not reflect some light, it would be invisible to the human eye. If it absorbed all the light that struck it, there would be nothing for your eye to see, because when you "see" the paper, you are actually detecting the light reflected from it. But a piece of paper is not a mirror, is it? So, what's the difference?

The difference is the amount of "scatter" or diffusion caused by the surface of the paper. When the light rays hit the surface of the paper, they don't bounce off in the same direction; they scatter in many directions. We characterize that phenomenon as diffuse reflection. This occurs because the surface of the paper, when viewed under a microscope, is uneven, granular, and bumpy. See the nearby link for a diagram of light rays hitting a surface and scattering. The rays are bouncing off in all different directions. Objects that produce diffuse reflections don't make very good mirrors.

But when light rays hit a very flat, smooth, polished surface, they bounce off at very predictable and consistent angles. They don't bounce off in all directions. In fact, the measure of the angle at which the light hits the surface (the angle of incidence) is the measure of the angle at which the light bounces off the surface (the angle of reflection). When this happens, you have a mirror. See the nearby link for a diagram depicting reflection.
the back of a mirror is a thin layer of metal. well polished metal reflects images.

Mirrors show reflection by light will reflect at a mirror surface so that the angles of incidence and reflection are equal.

Mirror has at least one reflective object so that shows the image, that you put in front of that mirror. And how they work is that light helps you see your reflection in a mirror ; Light is energy traveling at high speed.

And when it hits ah object all the energy has to go somewhere.

- Melissa Lindsay (:
The back part of the mirror is made of of metal. They polish the metal. Because metal reflects light if shows your reflection.

An aperature OS size a illluminated by a parallel beam sends diffracted light into a angle of approximately ~y/a. This is the angular size of the bright central maximum. In trevelling a distance z, the diffracted beam therefore acquires a width zy/a due to diffraction. this gives distance beyond which divergence of the beam of width a becomes significant. Therefore, z ~ a2/y we define a quantity ZF called the Fresenls distance by the following equation ZF= a2/y

For distance greater than ZF the spreading due to diffraction over that due to ray optics. The above equation shows that ray optics is valid in the limit of wavelength tending to zero.