Agilent/Keysight 81623A Optical Power Head

The Agilent/Keysight 81623A Optical Power Head is a germanium-based sensor for precise optical power measurement across the near-infrared spectrum. It operates with Agilent/Keysight 81618A or 81619A interface modules integrated into the 8163, 8164, and 8166 multichannel mainframe series. The 5 mm Ge sensor element delivers ±2.2% measurement uncertainty and linearity typically better than ±0.01 dB, supporting both single-mode and multimode fibers up to 100 µm core diameter with NA ≤ 0.3.

– Technical Specifications

• Sensor Element: Germanium (Ge), Ø 5 mm
• Wavelength Range: 750 nm to 1800 nm
• Power Range: +10 dBm to −80 dBm
• Measurement Uncertainty (1000 nm to 1650 nm): ±2.2%
• Return Loss: > 50 dB (typically > 55 dB)
• Linearity (within 10 dB of range maximum): Typically 50 dB
• Calibration stability: ±0.3% in second year post-calibration; add 0.01 dB typical for angled connectors

– Typical Applications

Optical component characterization, fiber-optic system power budgeting, wavelength-dependent attenuation measurement, and multiwavelength source characterization across the 750–1800 nm band.

– Compatibility & Integration

Requires Agilent/Keysight 81618A (single-channel) or 81619A (dual-channel) interface modules. Compatible with 8163A/B, 8164A/B, and 8166A/B mainframe series. Adapter selection available for popular fiber connector types, bare fibers, and free-space beams. Note: 81623A does not include analog output; the successor 81623B model provides this function.