Polarized Fiber Optic Source – High Extinction Ratio Laser and SLED Platform

The Polarized Fiber Optic Source (PFOSS) from OZ Optics is a precision light source engineered for applications where accurate and repeatable polarization control is critical. Designed around high‑quality laser diodes or superluminescent diodes (SLEDs), this instrument provides a stable, well‑defined state of polarization directly at the fiber interface. A rotatable polarizer integrated at the output, combined with a ruggedized housing and high‑quality connectors, enables users to finely tune the polarization angle for demanding laboratory, production, and metrology tasks.

In its standard configuration, the PFOSS features a fiber receptacle and a manually rotatable polarizer that allows adjustment of the polarization axis to any arbitrary angle. This makes it especially suitable for extinction ratio and polarization dependent loss measurements, where the linear polarization state must be precisely aligned with the device under test. For users who require automated and highly repeatable control, motorized versions (MPFOSS) are available with sub‑degree rotational resolution (as fine as 0.1°), controlled through an external touchscreen interface and graphical user interface. This combination of mechanical precision and optical quality delivers a high polarization extinction ratio, typically up to 40 dB, which is on par with or better than many comparable polarized sources used in fiber optic test benches worldwide.

Beyond the receptacle‑style configuration, OZ Optics also offers models with permanently attached polarization‑maintaining (PM) fiber. In these versions, the output polarization is aligned with the slow axis of the PM fiber, providing a defined and stable polarization reference for integration into larger systems or for use as a calibration source. This design minimizes uncertainty due to connector repeatability and simplifies setup in automated or field‑deployable systems. Compared to many generic polarized laser modules on the market, the PFOSS line offers a broader choice of connector options, wavelengths, and fiber types, giving integrators more flexibility in matching the source to existing networks, instruments, and test fixtures.

Power stability and spectral integrity are central to the PFOSS design. An optional integrated blocking‑style optical attenuator allows users to adjust the output power manually without altering the laser’s spectral characteristics. Unlike electronic power control methods that can impact wavelength, linewidth, or coherence, this purely optical attenuation approach helps maintain consistent spectral properties during calibration, R&D, or quality control runs. For further improvement in measurement repeatability, OZ Optics recommends the use of angled physical contact (APC) connectors and matching angled receptacles, which significantly reduce back‑reflections that can destabilize both power and polarization in precision setups.

For applications that place extreme demands on stability—such as long‑term polarization monitoring, interferometric systems, and high‑precision PDL characterization—OZ Optics offers several upgrade paths within the same product family. Selecting a superluminescent diode in place of a traditional laser diode can mitigate coherence‑related effects and reduce sensitivity to reflections, leading to smoother polarization behavior over time. Additionally, the Highly Stable Polarized Fiber Optic Source (HIPFOSS) variants integrate Peltier temperature control and optical isolators to tightly regulate output power and wavelength. Compared with conventional benchtop polarized lasers, these thermally stabilized solutions provide superior long‑term drift performance, making them well suited for standards labs and automated production test lines.

The PFOSS platform is available over a wide range of wavelengths commonly used in fiber optics, including 1550 nm configurations such as the 1 mW FC/APC and Super/Ultra receptacle models. Its compact mechanical footprint and robust construction are designed for both laboratory optical tables and industrial rack or production environments. A wide selection of connector types, including FC/APC and high‑grade ultra‑polished interfaces, ensures compatibility with modern telecom and photonics components. Optional higher‑power variants are offered for applications requiring increased launch power into fiber while still maintaining a clean, well‑defined polarization state.