This Service Manual i s Dedicated t o. FIRST -- - Lawn-Boy Service Accountseverywhere. MANUAL: DESCRIPTION: 1: A5HQ5851-01: Cat Blades (Electronic Only)/Canadian French: 2: ACHQ5410-02: Backhoe Loader Work Tools (ESL Only)/Chinese: 3: AECJ0001-00. Custom Color Set - The color of each element of the display can be configured independently with a serial console and a text menu, displayed by the firmware. Search or upload videos. Popular on YouTube: Music, Sports, Gaming, Movies, TV Shows, News, Spotlight. Optical fiber - Wikipedia, the free encyclopedia. A bundle of optical fibers. Fiber crew installing a 4. Midtown Manhattan, New York City. A TOSLINK fiber optic audio cable with red light being shone in one end transmits the light to the other end. An optical fiber (oroptical fibre) is a flexible, transparent fiber made by drawing glass (silica) or plastic to a diameter slightly thicker than that of a human hair. Fibers are used instead of metal wires because signals travel along them with lesser amounts of loss; in addition, fibers are also immune to electromagnetic interference, a problem from which metal wires suffer excessively. Here is the 4th episode of our animated series for Red Bull Music Academy featuring Lunice, Ango and 247esp. The artists discuss creating an album together in a car. Light is kept in the core by the phenomenon of total internal reflection which causes the fiber to act as a waveguide. Multi- mode fibers generally have a wider core diameter and are used for short- distance communication links and for applications where high power must be transmitted. For applications that demand a permanent connection a mechanical splice which holds the ends of the fibers together mechanically could be used or a fusion splice that uses heat to fuse the ends of the fibers together could be used. Temporary or semi- permanent connections are made by means of specialized optical fiber connectors. This particular illustration comes from a later article by Colladon, in 1. Guiding of light by refraction, the principle that makes fiber optics possible, was first demonstrated by Daniel Colladon and Jacques Babinet in Paris in the early 1. John Tyndall included a demonstration of it in his public lectures in London, 1. When the ray passes from water to air it is bent from the perpendicular.. If the angle which the ray in water encloses with the perpendicular to the surface be greater than 4. The angle which marks the limit where total reflection begins is called the limiting angle of the medium. For water this angle is 4. Learn how to do just about everything at eHow. Find expert advice along with How To videos and articles, including instructions on how to make, cook, grow, or do. Professional Plastics Site Map contains links to product pages within professional plastics website. Link to plastic sheets, rods, tubing and film. Pilot Equipment classifieds You must log in to post your classified adverts. If you haven't already registered, you can do so by visiting our registration page. Unbiased professional product reviews of TVs, laptops, cell phones, and more by reviewers who speak your language. Image transmission through tubes was demonstrated independently by the radio experimenter Clarence Hansell and the television pioneer John Logie Baird in the 1. The principle was first used for internal medical examinations by Heinrich Lamm in the following decade. Modern optical fibers, where the glass fiber is coated with a transparent cladding to offer a more suitable refractive index, appeared later in the decade. Harold Hopkins and Narinder Singh Kapany at Imperial College in London achieved low- loss light transmission through a 7. Their article titled . Wilbur Peters, and Lawrence E. Curtiss, researchers at the University of Michigan, in 1. In the process of developing the gastroscope, Curtiss produced the first glass- clad fibers; previous optical fibers had relied on air or impractical oils and waxes as the low- index cladding material. A variety of other image transmission applications soon followed. In 1. 88. 0 Alexander Graham Bell and Sumner Tainter invented the Photophone at the Volta Laboratory in Washington, D. C., to transmit voice signals over an optical beam. In the late 1. 9th and early 2. At the time, the use in the cameras was classifiedconfidential, and employees handling the cameras had to be supervised by someone with an appropriate security clearance. Hockham of the British company Standard Telephones and Cables (STC) were the first to promote the idea that the attenuation in optical fibers could be reduced below 2. B/km), making fibers a practical communication medium. They correctly and systematically theorized the light- loss properties for optical fiber, and pointed out the right material to use for such fibers . This discovery earned Kao the Nobel Prize in Physics in 2. Maurer, Donald Keck, Peter C. Schultz, and Frank Zimar working for American glass maker Corning Glass Works, now Corning Incorporated. They demonstrated a fiber with 1. B/km attenuation by dopingsilica glass with titanium. A few years later they produced a fiber with only 4 d. B/km attenuation using germanium dioxide as the core dopant. Such low attenuation ushered in the era of optical fiber telecommunication. In 1. 98. 1, General Electric produced fused quartzingots that could be drawn into strands 2. The erbium- doped fiber amplifier, which reduced the cost of long- distance fiber systems by reducing or eliminating optical- electrical- optical repeaters, was co- developed by teams led by David N. Payne of the University of Southampton and Emmanuel Desurvire at Bell Labs in 1. Robust modern optical fiber uses glass for both core and sheath, and is therefore less prone to aging. It was invented by Gerhard Bernsee of Schott Glass in Germany in 1. The first photonic crystal fibers became commercially available in 2. It is especially advantageous for long- distance communications, because light propagates through the fiber with little attenuation compared to electrical cables. This allows long distances to be spanned with few repeaters. The per- channel light signals propagating in the fiber have been modulated at rates as high as 1. Gbit/s) by NTT. The net data rate (data rate without overhead bytes) per fiber is the per- channel data rate reduced by the FEC overhead, multiplied by the number of channels (usually up to eighty in commercial dense WDM systems as of 2. This is because a single fiber can carry much more data than electrical cables such as standard category 5 Ethernet cabling, which typically runs at 1. Mbit/s or 1 Gbit/s speeds. Fiber is also immune to electrical interference; there is no cross- talk between signals in different cables, and no pickup of environmental noise. Non- armored fiber cables do not conduct electricity, which makes fiber a good solution for protecting communications equipment in high voltage environments, such as power generation facilities, or metal communication structures prone to lightning strikes. They can also be used in environments where explosive fumes are present, without danger of ignition. Wiretapping (in this case, fiber tapping) is more difficult compared to electrical connections, and there are concentric dual- core fibers that are said to be tap- proof. For example, most high- definition televisions offer a digital audio optical connection. This allows the streaming of audio over light, using the TOSLINK protocol. Advantages over copper wiring. The optical fiber is electrically non- conductive, so it does not act as an antenna to pick up electromagnetic signals. Information traveling inside the optical fiber is immune to electromagnetic interference, even electromagnetic pulses generated by nuclear devices. Low attenuation loss over long distances. Attenuation loss can be as low as 0. B/km in optical fiber cables, allowing transmission over long distances without the need for repeaters. Electrical insulator. Optical fibers do not conduct electricity, preventing problems with ground loops and conduction of lightning. Optical fibers can be strung on poles alongside high voltage power cables. Material cost and theft prevention. Conventional cable systems use large amounts of copper. Global copper prices experienced a boom in the 2. Security of information passed down the cable. Copper can be tapped with very little chance of detection. Sensors. In some applications, the sensor is itself an optical fiber. In other cases, fiber is used to connect a non- fiberoptic sensor to a measurement system. Depending on the application, fiber may be used because of its small size, or the fact that no electrical power is needed at the remote location, or because many sensors can be multiplexed along the length of a fiber by using different wavelengths of light for each sensor, or by sensing the time delay as light passes along the fiber through each sensor. Time delay can be determined using a device such as an optical time- domain reflectometer. Optical fibers can be used as sensors to measure strain, temperature, pressure and other quantities by modifying a fiber so that the property to measure modulates the intensity, phase, polarization, wavelength, or transit time of light in the fiber. Sensors that vary the intensity of light are the simplest, since only a simple source and detector are required. A particularly useful feature of such fiber optic sensors is that they can, if required, provide distributed sensing over distances of up to one meter. In contrast, highly localized measurements can be provided by integrating miniaturized sensing elements with the tip of the fiber. A major benefit of extrinsic sensors is their ability to reach otherwise inaccessible places. An example is the measurement of temperature inside aircraftjet engines by using a fiber to transmit radiation into a radiation pyrometer outside the engine. Extrinsic sensors can be used in the same way to measure the internal temperature of electrical transformers, where the extreme electromagnetic fields present make other measurement techniques impossible. Extrinsic sensors measure vibration, rotation, displacement, velocity, acceleration, torque, and twisting. A solid state version of the gyroscope, using the interference of light, has been developed. The fiber optic gyroscope (FOG) has no moving parts, and exploits the Sagnac effect to detect mechanical rotation. Common uses for fiber optic sensors includes advanced intrusion detection security systems. The light is transmitted along a fiber optic sensor cable placed on a fence, pipeline, or communication cabling, and the returned signal is monitored and analyzed for disturbances. This return signal is digitally processed to detect disturbances and trip an alarm if an intrusion has occurred. Optical fibers are widely used as components of optical chemical sensors and optical biosensors. They are used as light guides in medical and other applications where bright light needs to be shone on a target without a clear line- of- sight path. In some buildings, optical fibers route sunlight from the roof to other parts of the building (see nonimaging optics). Optical fiber lamps are used for illumination in decorative applications, including signs, art, toys and artificial Christmas trees.
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