Agilent / Keysight 81980A 1465-1575nm Tunable Laser Source

The Keysight 81980A is a tunable laser source covering the S+C-band (1465–1575 nm) for precision optical component and system characterization. This compact, single-slot plug-in module integrates into Keysight 8163A/B, 8164A/B, and 8166A/B mainframes, delivering mode-hop free tunability with exceptional wavelength accuracy and flat output power across its 110 nm tuning range. Built-in wavemeter feedback and coherence control enable stable operation in demanding single-channel and DWDM test environments.

Technical Specifications

Wavelength Range: 1465 nm to 1575 nm (110 nm total tuning span) Output Power: +13 dBm maximum; mode-hop free at ≥ +10 dBm flat output power Wavelength Accuracy & Stability:

• Absolute accuracy: ±20 pm (±5 pm typical)


• Relative accuracy: ±10 pm (±5 pm typical)


• Resolution: 1 pm / 125 MHz at 1550 nm


• Repeatability: ±2.5 pm (±0.3 GHz) typical


• 24-hour stability: ±2.5 pm (±0.3 GHz) typical Linewidth & Coherence:


• Narrow linewidth: 50 MHz at maximum constant output power


• Built-in SBS and interference suppression Power Control:


• Stability (1 hour): ±0.03 dB typical


• Stability (24 hours): ±0.03 dB typical


• Flatness (full range): ±0.2 dB typical


• Repeatability: ±0.08 dB typical Signal Quality:


• Side-mode suppression ratio: ≥ 50 dB


• Signal-to-ASE ratio: ≥ 45 dB/nm (full range, +10 dBm); ≥ 50 dB/nm (1525–1620 nm, +12 dBm)


• Signal-to-total ASE: ≥ 25 dB (full range); ≥ 30 dB (1525–1620 nm)


• Relative intensity noise: -145 dB/Hz (0.1–6 GHz) typical Tuning Performance: Mode-hop free across entire range; maximum sweep speed 50 nm/s; continuous dynamic wavelength logging

Key Features

• Closed-loop wavemeter feedback ensures ±5 pm absolute accuracy (typical)


• Flat output power response across 110 nm span


• Stimulated Brillouin scattering suppression prevents reflection-induced anomalies


• High-resolution 1 pm wavelength stepping


• Exceptional long-term stability (±2.5 pm over 24 hours)

Typical Applications

• Optical amplifier characterization (gain, noise figure)


• Passive component testing (filters, multiplexers, isolators)


• DWDM system validation


• Nonlinear fiber effects investigation


• Component wavelength-dependent performance mapping

Compatibility & Integration Plug-in module for Keysight 8163A/B, 8164A/B, and 8166A/B optical test mainframes, enabling flexible single-slot configuration for modular test benches.