• 40 GHz, 850 nm version for multimode fiber
  • 40 GHz and 70 GHz versions for single mode fiber (1.3 µm/ 1.55 µm windows)
  • Wide operating wavelength range
  • Average optical power measurement uncertainty: ≤ ±0.5 dB

The N4377A Lightwave Detector is a self-contained, USB-powered optical-electrical converter with built-in optical power meter capability. With amplitude and phase response calibration data stored on board the device, vector network analyzers (such as PNA, PNA-X) can de-embed the converter from optical transmitter or modulator measurements, enabling accurate S21-parameter measurements in the photonic domain. Electrical spectrum analyzers benefit from the converter’s low intrinsic noise and high bandwidth when performing laser linewidth and modulation spectrum measurements.

The built-in, calibrated optical power meter provides average power measurements and enables optical insertion loss measurements. A bar-graph display on the converter indicates detect bent or broken fibers, bad connectors or missing signal, and helps stay within the detector’s linear optical power range.

The N4377A Lightwave Detector is available for single-mode fiber with 40 GHz and 70 GHz bandwidth with calibration wavelengths at 1310 nm and 1550 nm. The 40 GHz version’s operating wavelength range starts at 1064 nm and ends at 1650 nm. The 70 GHz version operates across and beyond the entire CWDM range, starting at 1200 nm and reaching to 1650 nm.

The 40 GHz, multimode fiber version of the N4377A Lightwave Detector is calibrated at 850 nm but can also be operated at SWDM wavelengths and up to 1600 nm.

Learn more about Keysight Lightwave Component Analyzers

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Key Specifications

Frequency Range
DC to 70 GHz
DC to 43.5 GHz
Frequency Range
DC to 70 GHz
DC to 43.5 GHz
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Fiber Mode:
Single-mode & Multimode
Frequency Range:
DC to 70 GHz
DC to 43.5 GHz
Receiver Wavelength Range:
850 nm
1260 nm - 1650 nm
Relative Uncertainty (typical):
± 1.1 dBe @ 10 MHz-26.5 GHz; ±1.4 dBe @ 40 GHz
Lightwave Transmitter Analyzer Bundle
Wavelength Options:
1310 nm|1550 nm|850 nm

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