Agilent / Keysight 81949A 1520nm-1630nm Tunable Laser Source

The Keysight 81949A is a tunable laser source module delivering precise wavelength control across the C and L bands (1520 nm to 1630 nm). This plug-in instrument generates up to +13 dBm output power with ±100 pm absolute wavelength accuracy and mode-hop-free tunability across its full 110 nm range. Built-in coherence control, SBS suppression, and an integrated wavemeter (±20 pm accuracy) enable demanding single-channel and DWDM test applications in telecommunications and optical networking environments.

Technical Specifications

• Wavelength Range: 1520 nm to 1630 nm


• Tuning Range: 110 nm (C + L band)


• Output Power: ≥ +13 dBm (1570 nm to 1620 nm); ≥ +10 dBm (full range); typical peak ≥ +14.5 dBm


• Absolute Wavelength Accuracy: ±100 pm


• Relative Wavelength Accuracy: ±50 pm


• Wavelength Resolution: 5 pm (625 MHz @ 1550 nm)


• Mode-Hop-Free Tunability: Full range


• Tuning Speed: Typical 3 seconds for 100 nm sweep


• Power Linearity: ±0.1 dB


• Power Stability: ±0.03 dB over 24 hours (typical)


• Power Flatness: ±0.2 dB typical (full range); ±0.1 dB (1570 nm to 1620 nm)


• Side-Mode Suppression Ratio (SMSR): ≥ 50 dB (typical)


• Signal-to-Source Spontaneous Emission Ratio: ≥ 48 dB/nm (1570 nm to 1620 nm); typical 60 dB/0.1 nm


• Linewidth: 100 kHz (coherence control off); > 50 MHz (coherence control on, 1570 nm to 1620 nm)


• Wavelength Stability: ±5 pm over 24 hours (typical)


• Built-in Wavemeter Accuracy: ±20 pm absolute

Key Features

• Coherence control for extended effective linewidth


• Stimulated Brillouin Scattering (SBS) suppression


• Integrated wavemeter for absolute wavelength verification


• BNC front-panel input for external voltage control (±5 V maximum)


• GPIB and front-panel button control interfaces

Typical Applications

• DWDM system characterization and component testing


• Single-channel optical receiver and transmitter validation


• Wavelength-dependent loss and dispersion measurement


• Fiber optic and optical network research and development

Compatibility & Integration Plug-in module compatible with Keysight 8163A/B, 8164A/B, and 8166A/B mainframes.