Agilent/Keysight 81610A Tunable Laser Module (1490–1630 nm)

The Agilent/Keysight 81610A Return Loss Module is a precision optical test instrument for measuring return loss and reflection in single-mode fiber optic components. It operates by simultaneously measuring incident and reflected optical power to calculate return loss with high accuracy. The module delivers greater than 70 dB dynamic range and return loss uncertainty down to ±0.25 dB with broadband sources.

– Technical Specifications

• Return Loss Dynamic Range: >70 dB
• Return Loss Uncertainty: ±0.25 dB (broadband source); <±0.25 dB relative uncertainty at RL = 55 dB
• Wavelength Range (external input): 1250 nm to 1640 nm
• External Input Power: 0 dBm to 10 dBm
• Sensor Element: InGaAs photodiode
• Fiber Type: Standard single-mode 9/125 µm
• Input Connector: Angled contact (8°) interface
• Storage/Shipping Temperature: −40°C to +70°C

– Key Features

• Requires external laser source (no internal laser)
• Built-in power monitor and guided wizard (8163B mainframe with RTL-wizard)
• Integrated dark current mitigation and residual backscatter compensation
• Connector support: E-2000 (physical contact), SC, FC (narrow keyway), DIN 47256/4108, and LC
• Includes power sensor, monitor diode, and two optical couplers
• Fault-condition safety circuitry disables optical output

– Typical Applications

Return loss and reflection measurements in fiber optic components across the C-band and extended wavelength ranges; automated swept-wavelength characterization using external tunable sources.

– Compatibility & Integration

The module integrates with Keysight 8163A/B Lightwave Multimeter, 8164A/B Lightwave Measurement System, and 8166A/B Lightwave Multichannel System mainframes. Compatible with fixed-wavelength and tunable laser sources within the 1250–1640 nm range. The 81610CC calibrated reference cable and 816x Plug and Play Driver enable automated measurement workflows.