Polarization Maintaining Optical Isolator 1310nm 1480nm 1550nm For EDFA Fiber Laser Fiber Sensor

  The Polarization Maintaining Isolator is a unidirectional optical transmission device designed for polarization-sensitive systems. It primarily operates in three common wavelength bands: 1310nm / 1480nm / 1550nm, used to block back-reflected light, protect upstream components, and improve system stability. The product is available in Single Grade and Dual Grade configurations, and P/A accuracy levels, with peak isolation reaching up to 58 dB. It maintains low insertion loss and high isolation performance across a full temperature range of -5 to +70 °C. The device uses Corning panda-type polarization-maintaining fiber and can be selected for "slow axis only" or "dual-axis operation" modes, making it suitable for various polarization-maintaining applications such as EDFAs, fiber lasers, fiber optic sensors, and precision optical instruments.

• Low Insertion Loss, Less Link Budget Pressure

    At 23°C, the typical insertion loss of a single-stage isolator is only 0.4–0.6 dB, and for a two-stage structure, it is only about 0.5–0.6 dB. Even within a temperature range of -5 to +70°C, the upper limit of insertion loss is controlled at ≤0.55–0.80 dB, which helps maintain system OSNR and power margin.

• High Isolation, Effective Suppression of Backlight

    The peak isolation for single-stage P/A stages is 42/40 dB, and the peak isolation for two-stage P/A stages can reach 58/55 dB. At the actual operating point (23°C), it still provides ≥28/≥26 dB (single-stage) and ≥48/≥45 dB (two-stage), which can significantly suppress reflected light and crosstalk signals backfeeding into the laser or amplifier.

• High Extinction Ratio, Selectable Slow-Axis or Dual-Axis Operation

  Two polarization operating modes are provided:

  • Type 1: Fast axis blocked, extinction ratio ≥20 / ≥18 dB, suitable for classic polarization-maintaining links that only require slow-axis operation;
  • Type 2: Both axis working, extinction ratio ≥25 / ≥23 dB, suitable for special systems requiring dual polarization states.

  Simultaneously, the PM fiber and connector keying are aligned with the slow axis, ensuring clear and easy control of the polarization direction.

• High Return Loss and Good Power Handling Capability

    Return loss ≥55 dB, maximum input optical power ≤300 mW, effectively reducing the impact of end-face reflections on pre-amplifier devices, ensuring long-term stable operation in most communication and experimental platforms.

• Multi-wavelength coverage for unified platform design

    A single series covers three mainstream wavelength bands: 1310 / 1480 / 1550 nm, providing a unified isolation solution for amplifiers, laser sources, pump/signal links, etc., facilitating serialized design and inventory management for OEMs and system integrators.

• Clear performance estimates with connectors

    The specifications clearly state that the version with connectors has an increase of approximately 0.3 dB in insertion loss, a decrease of approximately 5 dB in return loss, and a decrease of approximately 2 dB in extinction ratio, which is beneficial for accurate link budgeting and performance evaluation during the solution phase.

  To meet different wiring and installation requirements, polarization-maintaining isolators are offered in two mainstream packages:

• P1 Steel Tube Package
  • Dimensions: φ5.5 * L35 mm steel tube, only suitable for bare fiber or 0.9 mm loose tube pigtails.
  • Typical Structure (see schematic on page 2): The central section is a φ5.5 mm * 35 mm body, with approximately 1000±50 mm polarization-maintaining optical fibers extending from each end. It is typically equipped with FC/APC connectors, resulting in a compact overall structure suitable for internal module installation or integration into compact devices.
• P2 ABS Box Packaging
  • Dimensions: L90 * W20 * H10 mm, suitable for 2.0 mm or 3.0 mm fiber optic cables.
  • Suitable for rack-mounted equipment or enclosure mounting, facilitating cable management and securing, resulting in a cleaner appearance.
• Fiber Optic Fiber and Connection Method
  • Fiber Type: Corning PM Panda Fiber, 1310nm model with PM1310, 1550nm model with PM1550.
  • Standard Pigtail Length: 1 m (customizable to project requirements).
  • Connectors: Optional FC/UPC, FC/APC, SC/UPC, SC/APC, LC/UPC, LC/APC, etc. Connector key alignment with the slow axis, fast axis blocking.

• EDFA (Erbium-Doped Fiber Amplifier)
• Fiber Optic Instrument
• Fiber Laser
• Fiber Sensor