Magnifying Visors

How do fiber optics work?

I know fiber optics are made of glass, but how do they get them to bend in a cable? it is just a property of glass to be flexible when its in really thin rods or what?

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1. The glass core in a fibre optic cable has a maximum bend radius, if you try to make a tighter bend it shall snap/buckle just like a large circular pipe would. Also as the light is fired down this core it bounces off the sides until it reached the end of the core, if the bend radius is too tight it will give additional losses in the information being sent.
2. In practical fibers, the cladding is usually coated with a tough resin buffer layer, which may be further surrounded by a jacket layer, usually plastic. These layers add strength to the fiber but do not contribute to its optical wave guide properties. For indoor applications, the jacketed fiber is generally enclosed, with a bundle of flexible fibrous polymer strength members like Aramid (e.g. Twaron or Kevlar), in a lightweight plastic cover to form a simple cable. Each end of the cable may be terminated with a specialized optical fiber connector to allow it to be easily connected and disconnected from transmitting and receiving equipment. For use in more strenuous environments, a much more robust cable construction is required. In loose-tube construction the fiber is laid helically into semi-rigid tubes, allowing the cable to stretch without stretching the fiber itself. This protects the fiber from tension during laying and due to temperature changes. Alternatively the fiber may be embedded in a heavy polymer jacket, commonly called "tight buffer" construction. These fiber units are commonly bundled with additional steel strength members, again with a helical twist to allow for stretching. http://www.lanshack.com/fiber-optic-tutorial-basics.aspx http://electronics.howstuffworks.com/fiber-optic4.htm Fiber optic cables work because of the way light behaves as it travels through a substance. Light travels well through air or glass, but poorly through substances like wood or metal. Light moves at different speeds in different media. It travels fastest through a vacuum, and slower through a medium like Earth’s atmosphere. As a result, where there is a boundary between different media, the direction of a light beam can be altered. We can measure this change, called the index of refraction. A fiber optic cable is made from a special medium that has two important properties: light travels easily through it, and the index of refraction is such that very little light can escape. To communicate using a fiber optic cable, a light source produces pluses of light that travel through the cable. These pulses carry information that can be translated into a picture or voice. If a pulse encounters the boundary between the cable and its neighboring medium, its direction is changed so it goes back in the cable. This effect, called total internal reflection, means those light pulses will be received at the other end of the cable without leaking out.