An optical splitter in a router or PON network divides a single incoming optical signal into multiple output signals, allowing one fiber to serve multiple users without active power.

Function and Role

An optical splitter is a passive device that takes a single optical signal from a central source, such as an Optical Line Terminal (OLT), and distributes it to multiple endpoints, like Optical Network Terminals (ONTs) in homes or offices . This enables cost-efficient sharing of a single fiber among many users, eliminating the need for separate fibers for each subscriber . Splitters are essential in Passive Optical Networks (PON), forming the backbone of FTTH deployments .

How It Works

The splitter operates without electricity, relying on light physics. Light traveling through the fiber is split by fusing and tapering fibers together or using planar lightwave circuits (PLC), creating multiple output paths . The key metrics include:

• Split Ratio: Determines how many outputs the input signal is divided into (e.g., 1:4, 1:32, 1:64). Higher ratios allow more users but reduce signal strength per output .
• Insertion Loss: The natural reduction in signal power caused by splitting. More outputs generally increase insertion loss .
• Uniformity: Ensures each output receives a consistent portion of the signal .

Types of Splitters

• FBT (Fused Biconical Taper) Splitters: Made by fusing and stretching fibers; suitable for small splits like 1:2 or 1:4 .
• PLC (Planar Lightwave Circuit) Splitters: Use integrated waveguide technology; ideal for large splits like 1:32 or 1:64, providing uniform output .

Additional Features

• Bidirectional Functionality: Most splitters can combine signals in the reverse direction, supporting two-way communication such as video calls .
• Compact Design: Small form factors allow installation in patch panels, optical distribution frames, or outdoor enclosures .
• Passive Operation: No power is required, making them reliable and low-maintenance . In summary, a router's optical splitter acts as a traffic distributor for light signals, efficiently sharing a single fiber among multiple users while maintaining signal quality and network scalability .