AOE Tech PMFOA Polarization-Maintaining In-Line Variable Optical Attenuator (SM/PM)

Overview

The AOE Tech PMFOA Polarization-Maintaining In-Line Variable Optical Attenuator is a precision passive component engineered for stable, low-loss attenuation of polarized light in single-mode (SM) and polarization-maintaining (PM) fiber-optic systems. Based on mechanically actuated variable gap or micro-electromechanical (MEMS)-assisted alignment principles—depending on configuration—the device achieves repeatable, wavelength-specific attenuation without compromising the polarization state of the input signal. It operates across four standard telecom and laser wavelengths: 980 nm, 1064 nm, 1310 nm, and 1550 nm, making it suitable for both R&D environments and production-grade coherent optical links, quantum photonics setups, and high-fidelity fiber sensor networks. Unlike generic attenuators, the PMFOA preserves the orientation of the slow axis relative to the connector key—ensuring alignment continuity in polarization-sensitive architectures such as interferometric sensors, polarization-encoded communication systems, and fiber-based gyroscopes.

Key Features

• Polarization-maintaining design with slow-axis alignment verified per IEC 61300-3-35; ER ≥20 dB (P-grade) ensures minimal crosstalk between orthogonal polarization modes
• Low typical insertion loss: ≤0.4 dB (P-grade) at 1310/1550 nm; ≤0.6 dB (P-grade) at 980/1064 nm—minimizing signal degradation in cascaded PM subsystems
• High directivity (>55 dB) suppresses back-reflections critical for laser diode protection and amplifier stability
• Thermally robust construction: operational range from −40 °C to +85 °C supports deployment in outdoor DWDM nodes and industrial laser enclosures
• Hermetically sealed stainless-steel or ceramic package options (Φ3 × 54 mm / Φ3 × 70 mm) provide mechanical stability under vibration and thermal cycling
• Configurable pigtails: 250 µm bare fiber, 900 µm loose tube, or custom jacketed variants—including 2 mm and 3 mm diameter options for high-power or ruggedized routing

Sample Compatibility & Compliance

The PMFOA is compatible with industry-standard Panda-type PM fibers (e.g., Thorlabs PANDA-980, Fujikura PM1550) and integrates seamlessly into assemblies requiring GR-1209-CORE-compliant mechanical interfaces. All units undergo 100% end-face inspection (IEC 61300-3-35) and polarization extinction ratio verification using calibrated polarimetric test sets. While not certified to ISO 9001 at the component level, AOE Tech’s manufacturing partners maintain ISO 9001:2015 quality management systems, and full traceability documentation—including spectral response curves, IL/ER histograms, and thermal drift data—is provided upon request for GMP/GLP-aligned validation protocols. The device meets RoHS Directive 2011/65/EU and REACH SVHC compliance requirements for restricted substances.

Software & Data Management

As a fully passive optical component, the PMFOA requires no firmware, drivers, or software integration. However, its performance parameters—including insertion loss tolerance vs. attenuation setting, polarization-dependent loss (PDL) <0.05 dB, and temperature-induced ER drift (<0.5 dB over full operating range)—are documented in standardized test reports compliant with Telcordia GR-1221-CORE Annex A. These reports support inclusion in FDA 21 CFR Part 11–aligned audit trails when deployed in regulated photonic medical devices (e.g., OCT systems, laser therapy platforms). For automated test setups, the PMFOA can be integrated into optical bench calibration sequences using programmable stage controllers and power meters (e.g., Keysight N77xx series), enabling batch characterization with statistical process control (SPC) logging.

Applications

• Power leveling in Er/Yb-doped fiber amplifiers (EDFAs/YDFAs) where PM pump/signal co-propagation demands polarization fidelity
• Reference channel attenuation in Michelson and Mach-Zehnder interferometers used for strain, temperature, or acoustic sensing
• Input power conditioning for high-speed coherent receivers (DP-QPSK, DP-16QAM) operating at 1064 nm or C-band
• Calibration-grade attenuation in metrology labs performing PM fiber splice loss benchmarking per IEC 61300-3-4
• Test fixture components in MIL-STD-883 optical subassembly qualification, particularly for aerospace-grade fiber optic gyroscopes (FOGs)
• Protection of sensitive photodetectors in LIDAR receiver chains using 980 nm or 1064 nm sources

FAQ

Is the PMFOA compatible with both FC/APC and FC/PC connectors?
Yes—standard configurations include FC/PC and FC/APC options; SC, LC, and custom terminations are available upon request with lead-time adjustment.

What is the maximum optical power handling capability?
The standard PMFOA is rated for continuous-wave (CW) power up to 500 mW. For high-power variants (1–10 W), contact engineering support for thermally optimized packaging and fused-silica collimation options.

Can the slow-axis alignment be customized to match a specific rotation angle?
Yes—axis alignment tolerance is ±1° relative to the connector key; angular customization (e.g., 0°, 45°, 90° offset) is supported for OEM integrators under NDA.

Do you supply test reports with each unit?
Each PMFOA ships with a factory test report listing measured IL, ER, directivity, and return loss at the specified wavelength and attenuation setting—traceable to NIST-calibrated reference standards.

Is there a version with electrical control interface?
AOE Tech offers an electronically controlled variant (PMFOA-E) with analog voltage (0–5 V) or digital RS-232 input for closed-loop attenuation tuning; inquire separately for specifications and lead time.