Since fiber splitters contain no electronics nor require power, they are an integral component and widely used in most fiber-optic networks. Fiber optic splitter, also referred to as optical splitter, fiber splitter or beam splitter, is an integrated waveguide optical power distribution device that can split an incident light beam into two or more light beams, and vice versa, containing multiple input and output ends. It can divide the input optical signal into multiple output optical signals to meet the fiber optic access needs of multiple terminal devices. Just like the old modems of the past. There is no power in the fiber signal just light Most likely, the modem isn't designed to work with fiber, it probably sends out signals on coax or some other more traditional medium. So something needs. A splitter is not a filter like a wavelength division multiplexer (WDM).
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