HP / Agilent 81531A POWER SENSOR MODULE

The HP/Agilent 81531A is an optical power sensor module engineered as a plug-in for the 8153A Lightwave Multimeter mainframe. It delivers accurate optical power measurements from 800 nm to 1700 nm using an InGaAs sensor element, with measurement range spanning +3 dBm to −90 dBm. The module combines high sensitivity and broad spectral coverage for telecommunications, fiber optics R&D, and manufacturing test environments. Rapid installation and removal minimize workflow disruption.

– Technical Specifications

• Sensor Element: InGaAs
• Wavelength Range: 800 nm to 1700 nm
• Power Measurement Range: +3 dBm to −90 dBm
• Accuracy (1000 nm to 1650 nm): ±2.5%
• Total Uncertainty (1000 nm to 1650 nm): ±5% ±1.5 pW; add 1% for full wavelength range
• Linearity (18°C to 28°C, 0 dBm to −70 dBm): ±0.015 dB ±1 pW
• Noise Floor (1 second averaging, 1200 nm to 1600 nm): <1.5 pW peak-to-peak
• Analog Output Bandwidth: DC to 300–4000 Hz (varies by range and module)
• Output Voltage: 0 to 2 V into open circuit
• Output Impedance: 600 Ω typical
• Maximum Input Voltage: ±10 V

– Key Features

• InGaAs photodiode optimized for near-infrared measurements
• Optical connector interface (FC/PC, ST, SC/PC, FC/APC available separately)
• Module dimensions: 37.5 mm diameter × 140 mm length
• Weight: 0.45 kg net
• Supported fiber types: 9/125 µm to 100/140 µm, NA ≤0.3
• Noise increases up to five times above stated range outside 1200–1600 nm

– Typical Applications

• Transmitter output power verification for laser diodes and LEDs
• Single-mode fiber link loss measurement during installation and maintenance
• Field-to-lab measurement validation
• Production power sweep automation

– Compatibility & Integration

Designed for the 8153A Lightwave Multimeter mainframe. Compatible with the 8163A mainframe. Not compatible with 8166 mainframe systems.