Understanding Polarization Maintaining Filter Couplers

A Polarization Maintaining Filter Coupler is a specialized device used for splitting or combining light without affecting its polarization state. Common applications include PM fiber interferometers, power sharing in polarization-sensitive systems, and signal monitoring in PM fiber setups. The device is designed with rugged stainless steel for optimal optical performance and stability.

The Significance of Extinction Ratio

One crucial feature of a Polarization Maintaining Filter Coupler is its “extinction ratio,” a measure of its ability to maintain polarization. A high extinction ratio indicates minimal mixing between polarization axes, ensuring superior performance.

Factors Affecting Extinction Ratio

The extinction ratio is influenced by the length of the fiber and environmental conditions. Factors such as high mechanical stress or tight bends can reduce the extinction ratio, impacting the device’s effectiveness.

Impact on System Performance and Other Parameters

A high extinction ratio plays a key role in improving the Bit Error Ratio (BER). This reduction in errors minimizes the need for error correction, especially in scenarios involving high data rates where errors can be more prevalent due to various factors.

Consequences of a Low Extinction Ratio

Conversely, a low extinction ratio results in a higher Power Penalty (PP), worsens the BER, and diminishes the advantages of increased power in the system.

Critical Importance of Extinction Ratio

For the Polarization Maintaining Filter Coupler to deliver quality and successful performance, a high extinction ratio is paramount. Variations in measured values between manufacturers and end-users can lead to reduced productivity, emphasizing the need to determine and ensure a high extinction ratio before purchasing the coupler.