Fiber signals work by transmitting light pulses through thin strands of glass or plastic, utilizing total internal reflection to guide the light along the fiber.
Here's a breakdown of how it works:
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Light Source: A laser or LED generates light pulses. These pulses represent the data being transmitted.
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Fiber Optic Cable Structure: A fiber optic cable consists of:
- Core: The central part of the fiber through which the light travels. It's made of glass or plastic.
- Cladding: A layer of glass or plastic surrounding the core. The cladding has a lower refractive index than the core.
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Total Internal Reflection: This is the key principle. When light traveling through the core hits the cladding at a shallow angle (greater than the critical angle), instead of passing through, it is reflected back into the core. This repeated reflection allows the light to travel long distances through the fiber. The light beam essentially "bounces" down the fiber.
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Signal Transmission: The light pulses are encoded with information. For example, the presence of a pulse can represent a '1', while the absence of a pulse can represent a '0'.
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Receiver: At the receiving end, a photodetector converts the light pulses back into electrical signals, which are then decoded to recover the original data.
In Summary: Fiber optic cables use light to transmit information. The light is guided through the core of the cable by continuous internal reflection, allowing data to be sent over long distances with minimal loss.
