They are constructed by fusing and tapering the fibers together. This method creates a simple, rugged, compact method of splitting or combining optical signals. Arrangements of mirrors or prisms used as camera attachments to photograph stereoscopic image pairs with one lens and one exposure are sometimes called "beam splitters", but that is a misnomer, as they are. Fused couplers are used to split optical signals between two (or more) fibers or to combine optical signals from two (or more) fibers into one fiber. It plays a crucial role in enabling multiple devices to share a single fiber optic connection, maximizing the utilization of the available. Beamsplitters are optical components used to split incident light at a designated ratio into two separate beams. Additionally, beamsplitters can be used in reverse to combine two different beams into a single one.
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