why the single mode graded index optical fiber is used and what its applications?
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Optical losses in a single mode optical fiber are smaller than in a multi mode optical fiber.  Therefore single mode fibers have more bandwidth and are used for a signal transmission over long distances.
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Elements of Photonics, Volume II by Keigo Iizuka\nISBN: 0471408158\n\nThe above book has a table of elasto-optic constants.
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Here is the real answer, not a made up one, not what I think, and not something I heard "sometime" from "someone".\n\nCountries like China, India, and Thailand have fiber optic networks because the networks they are putting in aren't replacing old ones, they are brand new.  These countries previously had very limited communications infrastructure.  When the time came they put in fiber optic because in the end it's more reliable, cost-effective, and can handle a lot more data.\n\nIn the case of COX, they handicap their modems programmatically to perform at lower speeds.  Business clients get the same modems, pay more and get faster download and upload speeds.  It's all about economics and sales.\n\nHowever, some telecom providers are pushing for legislation to control your bandwidth even further.  This way they will allow higher speeds for companies that pay them and lower for those that don't.  If you care about your internet speed the following site is definitely worth a look:  http://www.savetheinternet.com/
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You can get a hollow prism, fill it with water or some liquid and find its refractive index using a spectrometer. I did that for my ISC exam.
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(OTDR) is an optoelectronic instrument used to characterize an optical fiber.\nAn OTDR may be used for estimating the fiber's length and overall attenuation, including splice and mated-connector losses. It may also be used to locate faults, such as breaks.\nAn OTDR injects a series of optical pulses into the fiber under test. It also extracts, from the same end of the fiber, light that is scattered back and reflected back from points in the fiber where the index of refraction changes. (This is equivalent to the way that an electronic TDR measures reflections caused by changes in the impedance of the cable under test.) The intensity of the return pulses is measured and integrated as a function of time, and is plotted as a function of fiber length.
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It will be used in reference to a prism.\n\norange light has more wavelength thanx yellow.
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I agree that is is possible in some aspects. It would be impossible to avoid copper circuitry altogether (such as IC chip connections, etc.)\n\nElectricity travels through copper at 2/3 the speed of light. This slight gain in speed is slightly offset by the conversion from light to eletricity. However, this becomes trivial when you compare speeds. A single fiber optic cable can support data transfer rates of 10 Gb/sec or more. That is far beyond any personal computing requirements of today's computers.\nOptical fiber is also desirable because of it's electromagnetic immunity.
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The attenuation properties of the fiber is measured in decibels (dB). The attenuation of a length of fiber in dB is determined from the ratio of the input light power (P1) to the output light power at the far end of the fiber (P2) as\n\nAttenuation (dB)= 10 log(P1/P2).\n\nIn 1966 Charles Kao and George Hockham at Standard Telecommunications Laboratories Ltd. (STL) (now part of Nortel) pointed out that the attenuation of glass was largely caused by the presence of impurity metal ions, such as iron, copper, vanadium, and chromium, and that if a glass could be developed with attenuation of only 20 dB/km, then optical communication could become a reality. With such a fiber, 1% of the input light reaches the far end of a 1 km length of fiber.
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Refraction bent the light when passing in angle throught glass or other material, it can be use in a optical telescope. But the lens used must become thicker when diameter grow, and that make bigger lens really expensive.\n\nreflection can also be use to build telescope. Big mirror can be build at lower cost than lens.
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well.. refractive index is a function of frequency
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polarization is a way of filtering out all light except for the light that oscilates in a certain direction.  Light from the sun oscilates in all directions, but when it is reflected from a surface, it tends to oscillate very heavily in a single direction, which makes it amenable to filtering by polarlized lenses.  Sub glasses are therefore designed to minimize glare from reflected surfaces.  Some model cars also have polarized windshields for exactly the same reason - to minimize glare from sunlight bouncing off surfaces - like the hoods of other cars.  If you look through two polarized lenses, if the polarization of the two is parallel then most light passes through - but if they are perpendicular, then most light is blocked.  You are seeing light from the inside of a car that is passing through two polarized layers - that of the windshield and that of your glasses, and it is likely that the relative angle of alingment of the polarization between the two is somewhere between 0 and 90 degrees.  \n\nHere is something to try - next time you see a display of polarized sunglasses - hold one pair before your eyes - rotate the subglasses - and look at all the other polarized subglasses on the rack as you do so - you'll be amazed to see how all the glasses on the rack turn from clear to opaque as you rotate the pair in your hand
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diamond will have a huge refractive index because of its structure. that can be used to detect it.
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I had an essay on optical fibers last semester and this link was really, really helpful:\n\nhttp://electronics.howstuffworks.com/fiber-optic.htm\n\nWikipedia's not so bad too:\nhttp://en.wikipedia.org/wiki/Fiber_optics
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Ordinary glass is transparent to visible light due to an absence of electronic transition states in the range of visible light, and because ordinary glass is homogeneous on all length scales greater than about a wavelength of visible light. Ordinary glass partially blocks UVA (wavelength between 400 and 300 nm) and totally blocks UVC and UVB (wavelengths shorter than 300 nm) due to the addition of compounds such as soda ash (sodium carbonate).\n\nPure SiO2 glass (also called fused quartz) does not absorb UV light and is used for applications that require transparency in this region, although it is more expensive. This type of glass can be made so pure that, when made into fibre optic cables, hundreds of kilometres of glass are transparent at infrared wavelengths. Individual fibres are given an equally transparent core of SiO2/GeO2 glass, which has only slightly different optical properties . Undersea cables have sections doped with erbium, which amplify transmitted signals by laser emission from within the glass itself. Amorphous SiO2 is also used as a dielectric material in integrated circuits, due to the smooth and electrically neutral interface it forms with silicon.
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Infared (or Infrared) light is typically used to communicate through fiber optic cables.
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you can detailed info abt this at http://www.mae.usu.edu/faculty/bsmith/EFDL/array/Array.html and http://in3.dem.ist.utl.pt/downloads/lxlaser2000/pdf/34_2.pdf
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Hi, I think you're great, but i'm not going to type for 5 hours when all you needed to do was put "fibre optics" into the search engine. \nTry here:\nhttp://electronics.howstuffworks.com/fiber-optic1.htm