The Agilent 81689B is a compact C-band tunable laser module engineered for optical testing and measurement applications in DWDM systems. It delivers a stable, precise optical source across the entire C-band, enabling flexible test configurations for optical amplifiers, DWDM components, and related optical subsystems. The module supports both internal and external modulation with continuous sweep capability across its full wavelength range, and operates within Agilent’s modular lightwave measurement platforms.
## Technical Specifications
• **Wavelength Range:** 1525 nm to 1575 nm
• **Wavelength Resolution:** 0.01 nm (1.25 GHz at 1550 nm)
• **Absolute Wavelength Accuracy:** ±0.3 nm
• **Wavelength Repeatability:** ±0.05 nm
• **Wavelength Stability:** ±0.02 nm over 24 hours
• **Output Power:** ≥10 dBm
• **Output Power Stability:** ±0.03 dB over 1 hour; typical ±0.015 dB to ±0.0075 dB over 1 hour at constant temperature
• **Power Stability (typical):** <±0.025 dB over 1 minute
• **Spectral Linewidth:** 20 MHz (Option 021)
• **Tuning Speed:** <10 seconds per 50 nm
• **Maximum External Voltage:** ±6 V (per BNC connector)
## Key Features
• Tunable across full C-band (1525–1575 nm) with 0.01 nm resolution
• Dual modulation capability: internal and external
• Continuous sweep through entire wavelength range
• Single-mode fiber and polarization-maintaining fiber output options
• Straight or angled contact connectors available
• Class IIIb laser (FDA 21 CFR 1040.10); Class 3A (IEC 825-1:1993)
• Integrated safety circuitry disables optical output on fault detection
• NIST-traceable calibration with 2-year recommended recalibration interval
• Storage temperature range: -40 °C to +70 °C
## Typical Applications
• DWDM system characterization and component testing
• Optical amplifier performance validation
• Wavelength-dependent measurements across C-band
• Dynamic wavelength tuning in optical test configurations
## Compatibility & Integration
The 81689B integrates into Agilent 8163A/B Lightwave Multimeters, 8164A/B Lightwave Measurement Systems, and 8166A/B Lightwave Multichannel Systems. Pairs with the optional 81651A optical attenuator module to extend output power dynamic range.
