how optical fibres are constructed?
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Optical fiber is made by first constructing a large-diameter preform, with a carefully controlled refractive index profile, and then pulling the preform to form the long, thin optical fiber. The preform is commonly made by three chemical vapor deposition methods: inside vapor deposition, outside vapor deposition, and vapor axial deposition.\n\nIn inside vapor deposition, a hollow glass tube approximately 40 cm in length known as a "preform" is placed horizontally and rotated slowly on a lathe, and gases such as silicon tetrachloride (SiCl4) or germanium tetrachloride (GeCl4) are injected with oxygen in the end of the tube. The gases are then heated by means of an external hydrogen burner, bringing the temperature of the gas up to 1900 kelvins, where the tetrachlorides react with oxygen to produce silica or germania (germanium oxide) particles. When the reaction conditions are chosen to allow this reaction to occur in the gas phase throughout the tube volume, in contrast to earlier techniques where the reaction occurred only on the glass surface, this technique is called modified chemical vapor deposition.\n\nThe oxide particles then agglomerate to form large particle chains, which subsequently deposit on the walls of the tube as soot. The deposition is due to the large difference in temperature between the gas core and the wall causing the gas to push the particles outwards (this is known as thermophoresis). The torch is then traversed up and down the length of the tube to deposit the material evenly. After the torch has reached the end of the tube, it is then brought back to the beginning of the tube and the deposited particles are then melted to form a solid layer. This process is repeated until a sufficient amount of material has been deposited. For each layer the composition can be varied by varying the gas composition, resulting in precise control of the finished fiber's optical properties.\n\nIn outside vapor deposition or vapor axial deposition, the glass is formed by flame hydrolysis, a reaction in which silicon tetrachloride and germanium tetrachloride are oxidized by reaction with water (H2O) in an oxyhydrogen flame. In outside vapor deposition the glass is deposited onto a solid rod, which is removed before further processing. In vapor axial deposition, a short seed rod is used, and a porous preform, whose length is not limited by the size of the source rod, is built up on its end. The porous preform is consolidated into a transparent, solid perform by heating to about 1800 kelvins.\n\nThe preform, however constructed, is then placed in a device known as a drawing tower, where the preform tip is heated and the optic fiber is pulled out as a string. By measuring the resultant fiber width, the tension on the fiber can be controlled to maintain the fiber thickness.
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Fiber optic Telecommunications. By the 1000's
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Fiberglass or fibreglass is material made from extremely fine fibers of glass. It is used as a reinforcing agent for many plastic products; the resulting composite material, properly known as glass-reinforced plastic (GRP) or glass-fiber reinforced epoxy (GRE), is called "fiberglass" in popular usage.\n\nFormation\nGlass fiber is formed when thin strands of silica-based or other formulation glass is extruded into many fibers with small diameters suitable for textile processing. Glass is unlike other polymers in that, even as a fiber, it has little crystalline structure (see amorphous solid). The properties of the structure of glass in its softened stage are very much like its properties when spun into fiber. One definition of glass is "an inorganic substance in a condition which is continuous with, and analogous to the liquid state of that substance, but which, as a result of a reversible change in viscosity during cooling, has attained so high a degree of viscosity as to be for all practical purposes rigid."\n\nThe technique of heating and drawing glass into fine fibers has been known to exist for thousands of years; however, the concept of using these fibers for textile applications is more recent. The first commercial production of fiberglass was in 1936. In 1938, Owens-Illinois Glass Company and Corning Glass Works joined to form the Owens-Corning Fiberglas Corporation. Until this time all fiberglass had been manufactured as staple. When the two companies joined together to produce and promote fiberglass, they introduced continuous filament glass fibers.Owens-Corning is still the major fiberglass producer in the market today.\n\nManufacturing Processes\nThere are two main types of glass fiber manufacture and two main types of glass fiber product. First, fiber is made either from a direct melt process or a marble remelt process. Both start with the raw materials in solid form. The materials are mixed together and melted in a furnace. Then, for the marble process, the molten material is sheared and rolled into marbles which are cooled and packaged. The marbles are taken to the fiber manufacturing facility where they are inserted into a can and remelted. The molten glass is extruded to the bushing to be formed into fiber. In the direct melt process, the molten glass in the furnace goes right to the bushing for formation. \n\nThe bushing plate is the most important part of the machinery. This is a small metal furnace containing nozzles for the fiber to be formed through. It is almost always made of platinum alloyed with rhodium for durability. Platinum is used because the glass melt has a natural affinity for wetting it. When bushings were first used they were 100% platinum and the glass wetted the bushing so easily it ran under the plate after exiting the nozzle and accumulated on the underside. Also, due to its cost and the tendency to wear, the platinum was alloyed with rhodium. In the direct melt process, the bushing serves as a collector for the molten glass. It is heated slightly to keep the glass at the correct temperature for fiber formation. In the marble melt process, the bushing acts more like a furnace as it melts more of the material. \n\nThe bushings are what make the capital investment in fiber glass production expensive. The nozzle design is also critical. The number of nozzles ranges from 200 to 4000 in multiples of 200. The important part of the nozzle in continuous filament manufacture is the thickness of its walls in the exit region. It was found that inserting a counterbore here reduced wetting. Today, the nozzles are designed to have a minimum thickness at the exit. The reason for this is that as glass flows through the nozzle it forms a drop which is suspended from the end. As it falls, it leaves a thread attached by the meniscus to the nozzle as long as the viscosity is in the correct range for fiber formation. The smaller the annular ring of the nozzle or the thinner the wall at exi
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a school science project?\nhow about a demonstration of how light flows through fiber optic cable, how you can change the color with a color wheel, change the look with different diameter fiber cable and lengths. you could make a really cool display that looks like a galaxy or some celestial picture...only thing is it has to be viewed in complete darkness, so you may have to build it in a box- or just turn out the lights. you could relate how it has effected the telecommunications world, etc...\nonly thing is may be hard to find cable at a cheap price with out buying bulk- but if you are resourceful you may do it, or you could buy cheap pens, or a hobby store may carry it. then as a light source use an LED and make a color wheel with clear plastic sheeting and colored sharpie pens, and battery energy source.\n\nhttp://www.cablecominc.com/fiber.jpg\nhttp://www.network-cables-guide.co.uk/images/fibre-optic.jpg\nhttp://www.arcelect.com/fibercable.htm\nhttp://electronics.howstuffworks.com/fiber-optic.htm\nhttp://www.delmartrading.com/images/products/FiberOpticPen.jpg\n\ngood luck, have fun
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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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It's what you peer into. There's a diagram here:\n\nhttp://en.wikipedia.org/wiki/Optical_microscope
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Optical fibers act light light tubes.  It is as if the internal walls of the fiber are coated with a morrored substance.  Whenever the light traveling down the fiber tries to exite through the wall of the fiber the ligt is reflected back into the firber path.  So almost 100% of the light entering, exists at the other end.\n\nSince th fibers transmit light which moves faster than any other phenomenon on Earth, optucal fibers are perfect for use in High-speed communications applications.\n\nData is converted to digital signals and that it turned into a pattern of light which is transmiotted down the fiber.  With fiber optics we can rung Gigabytes fo data in places were only kiliobyts of data was transmitted before.\n\nThere are also medical applications for fiber optics where small cameras can be inseted into the human boody and the images from the camera are sent over a fibe optic line to the doctor.
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I think you mean....can someone get a password out of a fiber optic system...?\n\nyes, but you have to splice into the fiber..and have an attached network card...or,\n\nbreak into a repeater or switch...
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(m)\n\nOptical networks are high-capacity telecommunications networks based on optical technologies and components that provide routing, grooming, and restoration at the wavelength level as well as wavelength-based services.\n\nAs networks face increasing bandwidth demand and diminishing fiber availability, network providers are moving towards a crucial milestone in network evolution: the optical network. Optical networks, based on the emergence of the optical layer in transport networks, provide higher capacity and reduced costs for new applications such as the Internet, video and multimedia interaction, and advanced digital services.\n\nAs with any new technology, many questions arise. How is the optical network different from existing networks? What are the network elements required for optical networks? What applications do optical networks best suit? This tutorial will address all of these questions and explain the technologies, architectures, and market trends for emerging optical networks.\n\nGoto the following link for more details\n\nhttp://www.iec.org/online/tutorials/opt_net/
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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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A Prism bends the light and separates it to the different colors, usually seen as rainbow colors or primary colors that all other colors come from the blending of these colors in one way or another.  An optical instrument gathers light bends it and projects it to your eye on the correct focal lengnth through the ocular lens or eyepiece.  It is the focusing of the instument that puts the color right again and projects the image to your eye.  You do not look through an optical instrument it is actually projecting an image to your eye the way a projector projects a movie to a screen.
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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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There should have been more to the question than that, but here goes...\n\nThe transmission media is the thing or stuff used to transmit the communication signals for a computer.  Until recently, that would have been the cable plugged in to the back of the machine.  Based on how much data it can carry it has a category or cat rating; the higher the number the more it can carry.  CAT3 is commonly used for voice and CAT5e or CAT6 is typical for a data installation.\n\nThere are also older standards like 10Base-2 and 10Base-5 that you don’t see too much anymore.\n\nFor longer lengths of cable, fiber optic cables are used to carry pulses of light sometimes 10 kilometers between endpoints.\n\nThe answer gets a little more complicated when you think about wireless.  Is the transmission media air?  Is it the antennas in the card or in the access point?
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I got most of my study aids from  this site.\n\nhttp://www.alibris.com/search/books/subject/Optoelectronics
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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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No, I saw something on TV where they had fiber optic cables around an object that would broadcast the image on the other side so it would "look" like it wasn't there.  The technology is used in the military but it wasn't perfect.  It kind of looked like those heat waves on the road on a hot day, so you could tell something was odd.
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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