N7747C and N7748C High-Sensitivity Optical Power Meters

Introduction

The 2-port N7747C and 4-port N7748C optical power meters provide the highest accuracy and sensitivity performance in compact front-panel sensor instruments. These are successors and direct replacements for the N7747A and N7748A and continue the optical performance level of the 81634B modules.

The N774-C Family’s Deepest Dynamic Range

With actively cooled InGaAs detectors and optimized high-performance analog electronics, these instruments provide the lowest level of noise and drift to provide a very low and stable zero-signal level. The very high linearity and low polarization dependence give peak accuracy over the full power range.

Analog output port perfect for automated alignment

The highest sensitivity and the analog voltage output make a powerful combination for use in operations for probe and fiber alignment and other optimization routines, where a very weak initial signal level must be detected and then tracked in real-time to increase the signal level over orders of magnitude. The voltage on each channel’s analog output port represents the optical power level.

Two and four port with user-exchangeable connector receptacles

N7747C is equipped with two power sensor channels, N7748C provides four power sensor channels. Each port accepts one of the proven 81000xI connector interfaces to adapt to common fiber-optic connector standards.

Members of a growing family

The N7747C and N7748C benefit from the N77-C’s family-wide, common trigger concept, and a modern, browser-accessible user interface, that makes it convenient to configure the instrument’s functionality. High-speed measurement data acquisition, faster data interfaces, the use of dual-ported RAM for uninterrupted simultaneous measurement and readout help avoid unnecessary delays in the measurement process as well as in post-processing.

Fast swept-wavelength measurements with high dynamic range

For the measurement of devices with very high isolation or very low PDL, the new N7747C and N7748C are alternatives to the N7744C and N7745C multiport power meters in swept-wavelength applications: Controlled by the photonic application software suite they can perform spectral measurements of insertion loss and polarization dependent loss when combined with Keysight tunable lasers and a polarization synthesizer. Use of multiple power ranges and bi-directional wavelength sweeping provide fast measurements with dynamic range beyond 80 dB. The photonic application software suite has a measurement engine for IL and PDL that can combine the sweeps of up to 3 tunable laser wavelength ranges. See the photonic application software suite brochure for details.

Key benefits

Highest accuracy and sensitivity for single measurements and optical power logging

• -110 to +10 dBm power range with very low noise and drift

• In-range linearity below ± 0.005 dB for highest IL measurement accuracy

• Very low polarization dependence for great stability and PDL accuracy

• Memory for 1 M samples/port plus 1 M/port buffer for continuous logging 

• Averaging times from 25 µs to 10 s per sample

Ideal for automated and semi-automated alignment applications

• Analog output with linear feedback for alignment

• Standard BNC connector with 0 to 2 V output 

Flexibility

• 81000xI connector interfaces support a wide range of common fiber-optic connectors

• The instrument can be controlled via LAN and USB

• The comprehensive hardware and trigger concept along with its large memory storage gives the flexibility to adapt the power meter to many test needs

• The instrument programming code is compatible to the Lightwave solution