Agilent/Keysight 8504B

The Agilent/Keysight 8504B Precision Reflectometer is a high-resolution optical instrument for measuring return loss in lightwave systems with exceptional sensitivity. Operating as an interferometer, it precisely locates, identifies, and quantifies individual reflections within optical components and assemblies—critical for design optimization and manufacturing troubleshooting. The instrument is optimized for single-mode fiber while delivering useful measurements in multi-mode fiber applications.

– Technical Specifications

Measurement Performance
• Return Loss Range: 10 dB to 80 dB
• Dynamic Range: Over 80 dB
• Return Loss Accuracy: ±2.0 dB
• Measurement Span: 1 mm to 400 mm (extendable with cables)
• Span Accuracy: ±2% (1–10 mm), ±1% (10–400 mm)
• Sweep Speed: 18 mm/sec
• Spurious Response: >65 dB below largest reflection

Spatial Resolution
• 1300 nm: 17 µm (typical), 25 µm (two-event separation)
• 1550 nm: 44 µm (typical), 65 µm (two-event separation)
• Two-Event Resolution: Identifies reflections 25 µm apart (air equivalent)

Optical Sources
• Internal Wavelengths: 1300 nm (±30 nm) and 1550 nm (±30 nm)
• Spectral Width (−3 dB): 55 nm
• Average Power: −17 dBm

– Key Features

• Dual internal wavelength sources for comprehensive reflection analysis
• Over 80 dB dynamic range enables detection of weak reflections in complex assemblies
• Micrometer-class spatial resolution facilitates precise event localization
• ±2.0 dB return loss accuracy suitable for component characterization and device validation
• GPIB remote control for automated test sequences
• FC/PC connectors for standard fiber interface

– Typical Applications

• Characterizing passive fiber-optic devices (couplers, attenuators, connectors, isolators)
• Measuring launch optics for lasers and opto-electronic integrated circuits (OEICs)
• High-resolution discontinuity measurements in lightwave paths
• Refractive index determination from known physical spacing
• Quality assurance in fiber-optic network component manufacturing

– Compatibility & Integration

Fiber Support: Single-mode fiber (9/125 µm); multi-mode fiber capable
Remote Interface: GPIB
Operating Environment: 20°C–30°C (±3°C drift limit from calibration)
Warm-up: 2 hours | Humidity: <95% non-condensing
Dimensions: 370 mm (H) × 460 mm (W) × 570 mm (D) | Weight: 28 lbs