Fiber optic communication relies on transmitting information as pulses of light through thin strands of glass or plastic called optical fibers. Instead of using electrical signals (like in traditional copper wires), it uses electromagnetic radiation in the form of light. In optical fiber communication, optical fiber modulation is the process of “loading data into optical signals”. Light itself is a single waveform and cannot directly carry complex information. Unlike copper wires, which send electrical signals and suffer from resistance and interference, fibre optics offer orders of magnitude more bandwidth and. Our eyes are sensitive to light whose wavelength is in the range of about 400 nanometers (billionths of a meter) to 700 nanometers, from the blue/violet to the red. If you wonder why this is the range of colors we can see, it's because it is the same region as the brightest output of the sun.
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