AQ6151B Optical Wavelength Meter

The AQ6151B Optical Wavelength Meter is an ideal instrument for accurately measuring the optical wavelength of optical devices and systems with wavelength ranges from 900 nm to 1700 nm. By employing a Michelson interferometer and a high speed Fast Fourier Transform (FFT) algorithm, the AQ6151B can measure not only a single wavelength laser signal, but also a multiple wavelength laser signal from a DWDM system and Fabry-Perot laser. Furthermore, this technology enables the measurement of modulated laser signals in addition to the CW signal from an optical transceiver. The optimized optical design and data processing routine significantly reduces the measurement time and improves manufacturing throughput.

  • High wavelength accuracy: ±0.2 ppm
  • Wavelength range (3 types): 900-1700nm, 1200-1700nm, 1270-1650nm
  • Measurement time of 0.2 seconds or less
  • Up to 1024 wavelengths can be measured at once
  • Single wavelength type and multi wavelength type
  • Support modulated light and filter measurement

Select type from wavelength range and number of detection

Model Wavelength Accuracy Number of wavelengths
High accuracy model
AQ6151B
Standard 1270 to 1650nm ±0.2ppm 1024 (Multi-wavelength type)
1 (Single-wavelength type)
Extended 1200 to 1700nm
Wide range 900 to 1700nm

High wavelength accuracy of ±0.2 ppm

The High Accuracy AQ6151B model offers an accuracy of ±0.2 ppm to meet the most demanding precision requirements.
The real time correction feature utilizes a highly stable reference signal from the built-in wavelength reference light source in order to provide long-term stability for each and every measurement taken.

CW, modulated transceiver and optical filter measurement

The optical output of optical transceivers and optical transmission systems is modulated with a transmission frequency including 10 G and 25 Gbps. The built-In Optical Spectrum Analysis capability utilizing an FFT technique is required to measure the spectrum broadened by the modulated signal.
In addition to the regular CW light mode, the AQ6151B has a modulated light mode. The modulated mode functions as an optical spectrum analyzer and discovers the center wavelength of the modulated light. This mode can also be used for the center wavelength measurement of optical filters such as a band pass filter, AWG and WSS.

Multi-wavelength type that simultaneously measures up to 1024 wavelengths

The Multi-wavelength type can measure up to 1024 wavelengths in a single input signal with a minimum separation of 5 GHz simultaneously, quickly, and accurately. This means it can meet testing needs in the development and production of WDM transmission system today and in the future as well. The multi-wavelength measurement capability contributes to production efficiency and cost reduction in the production of single-wavelength laser devices as well, by combining multiple laser modules or optical transceivers using an optical coupler and measuring all the signals at once.

Single-wavelength type

Inspection of the wafer and LD chip might be measured only a single wavelength. The single wavelength type is a low-cost optical light wavelength meter suitable for such applications.

Delivering high performance even with low-power input signals

Equipped with an Auto Gain Control (AGC) function, the AQ6151B adjusts the gain of the electrical amplifier automatically based on the input signal power. This helps maximize wavelength accuracy and measurement speed even if the input signal power is as low as −40 dBm.

Improve Productivity

Increase throughput with high speed measurement

For the adjustment and characterization of tunable laser sources and tunable optical transceivers requiring hundreds of wavelength measurements per device, high-speed measurement and processing capability are crucial for improving the production throughput.

The AQ6151B can acquire, analyze and transfer a measurement to a PC in less than 0.2 seconds! This is 2 times faster than our AQ6151 model, thus vastly improving production throughput. In the Repeat measurement mode, the AQ6151B can collect 10 measurements per second, making it extremely useful when adjusting a device while monitoring the wavelength in real time.

Improve Productivity
Upgrade the test system with ease

Upgrade the test system with ease

Easily build an automated measurement system using a remote control interface, ETHERNET or GP-IB.

The remote command set complies with the commonly accepted SCPI industry standard command set for programmable instruments. Thus, the existing measurement system can be easily upgraded without having to change the measurement program if Yokogawa AQ6140 series or another SCPI compatible optical wavelength meter is already in use.

Reduce lifetime ownership costs

With the conventional wavelength meters, the high failure rate of the wavelength reference light source and its high replacement costs have been a major contribution to the overall costs of ownership during the product life cycle, not to mention the costs generated by the downtime itself.

One of our key targets for product design was to address and mitigate as much as possible these issues. We achieved this goal in a multi-dimensional approach as represented graphically in the below scheme.

  • Extending the typical lifetime (MTBF) of the light source (Maximize Horizontal scale).
  • Reducing the replacement cost (Minimize Vertical scale).
Reduce lifetime ownership costs

User-friendly interfaces

USB ports

  • For USB compatible data storage devices. mouse, and keyboard.
  • File function enables users to save data and screenshots to the internal memory or USB storage to use when creating test reports. Screenshots can also be saved by simply pressing the Print Screen button (PRT SCN) located on the front panel.

USB ports

Easy to view bright color LCD

  • The AQ6151B screen design and intuitive interface is inherited from Yokogawa's best-selling optical spectrum analyzer.
  • This interface has been proven by a vast population of users on a global scale in areas such as R&D testing and troubleshooting in manufacturing.

Easy to view bright color LCD

Data access through LAN

The standard LAN port allows convenient access to files stored in the internal memory as well as the ability to remotely update the firmware from a PC.

Data access through LAN

Direct operation with mouse

  • Using a USB mouse makes it easy and intuitive to change measurement conditions, execute an analysis, and modify the optical spectrum view.
  • In the optical spectrum view, the waveform view area can be zoomed and shifted by a simple click and drag. The peak threshold line, threshold for peak detection, can also be moved in the same manner.

Direct operation with mouse

Items Functions
Measurement Single, repeat, average, drift, data logging
Measurement condition setup Average count, air/vacuum wavelength, device type (CQ/modulated,), measurement range
Display Single wavelength, multi-wavelength, delta, grid, spectrum, wavelength axis units, optical power units, center wavelength, total power, marker, label, power bar, warning messages, error messages, system information.
Data analysis Peak search, FP-LD analysis, drift analysis, WDM(OSNR) analysis
File Saving/loading measured results (CSV), saving/loading parameters (binary), saving screen images (BMP)
Remote control Interface selection (GP-IB/Ethernet), TCP/IP configuration, remote monitor
Others Internal reference light source on/off, internal reference light source status LED, optical power offset, parameter initialization, firmware updating

Various view modes

Single Wavelength Mode

The single wavelength mode displays the wavelength and power of the highest peak or an arbitrary peak using large easy to read numbers. This allows the values to be easily read even if the unit is placed at the top of the test stand.

Single Wavelength Mode

Multi Wavelength Mode

The multi wavelength mode displays a list of wavelengths and power of multiple peaks with the wavelength and power of the highest peak or an arbitrary peak on top of the list. There is also a mode to show the list only to maximize the number of channels shown on the screen.

Multi Wavelength Mode

Delta Wavelength Mode

The delta wavelength mode calculates and displays the difference between a reference peak and the other peaks in terms of wavelength and power. This mode helps determine the peak spacing.

Various Measurement Units

Choose from any of the following measurement units. 

  • Wavelength: Wavelength (nm), Frequency (THz), or Wave Number (cm-1
  • Power: dBm, mW, or μW

Grid Mode

Displays the deviation between a set grid wavelength and a measured wavelength which is within a set search area centering the set grid wavelength.​​​​

Grid Mode

Optical Spectrum View

The Multi-wavelength type can display an optical spectrum waveform obtained from a Fast Fourier Transform (FFT) algorithm. It allows for determining test conditions and for troubleshooting an error in the measurement while confirming the actual spectrum. When a peak is selected on the list, the peak automatically shifts to the center of the optical spectrum view, making viewing easy and convenient.

Optical Spectrum View

Efficient measurement & analysis functions

The AQ6151B is equipped with automatic measurement and analysis functions. These functions save valuable time and resources from creating/validating remote control and analysis programs.

Drift Analysis

The drift analysis measures the variation of wavelength and power for each peak over time by repeating the measurement. It obtains maximum value (MAX), minimum value (MIN), and variation (MAX-MIN). This function is useful for long-term stability testing and for evaluating the temperature dependency of lasers.​​​

Drift Analysis

Fabry-Perot Laser Analysis

The evaluation parameters of a Fabry-Perot laser can be analyzed and displayed instantly from the measured optical spectrum.

Results include: Center wavelength, total power, spectral-width (FWHM), mode spacing, etc.

Fabry-Perot Laser Analysis

Average Measurement

The average measurement obtains an average wavelength and power for each peak by repeating the measurement. This function helps reduce uncertainty of measurement for a modulated signal or unstable signals.

Data Logging Function

Up to 100001 points of measurement data per channel can be stored and displayed in tabular or graph form. It facilitates the long-term stability test and temperature cycle test.

How to Measure with a Light Wavelength Meter

1. Set the peak detection threshold and excursion values

2. Set the medium that light travels through

3. Set the wavelength and power units

4. Configure the CW light measurement, modulated light measurement, or high-speed measurement

5. Set the frequency tolerance

6. Press the SINGLE key for a single measurement. The SINGLE key illuminates to indicate that a measurement has started. When the measurement is complete, the SINGLE key turns off. The instrument measures once and displays the results on the screen.

7. Press the REPEAT key for repeated measurements. The REPEAT key illuminates to indicate that a measurement has started. Measurement is repeated until you press STOP.

WDM transmission systems

In order to meet the rigorous demands of current and next generation communication networks, developers are constantly challenged to improve the efficiency and capacity of the transmission system. In response to these challenges, various techniques have been developed, such as minimizing channel spacing, maximizing the number of channels and transmission rate, using sophisticated modulation schemes, etc.

In WDM transmission system testing, high wavelength accuracy is required for testing the system’s internal circuit boards such as laser modules and optical transceivers as well as the final output signal of the system, which may involve:

  • Simultaneous measurement of multi channel and narrow spacing WDM system.
  • Precise adjustment and inspection of laser sources.
  • Measurement of modulated signals.

Calibration of test systems

Due to the high accuracy of the AQ6151B, it can be used for precision wavelength calibration applications including:

  • Calibration of optical spectrum analyzers.
  • Calibration of DFB lasers for optical amplifier test system.
  • Calibration of tunable lasers for passive component test systems.

Lasers/optical transceivers

Testing of optical components used in WDM transmission systems such as laser devices, laser modules, and optical transceivers also requires high wavelength accuracy. These applications may include:

  • Precise adjustment and inspection of tunable lasers.
  • Modulated signal measurement of optical transceivers and transponders.
  • Measurement of all channels of 40 G and 100 G optical transceivers with WDM technology.

Lasers/optical transceivers

Michelson interferometer

Generate interference by changing the optical path length difference between the fixed mirror and the movable mirror. Then detect the interference signal with the optical receiver.

Fast Fourier transform (FFT)

Convert the interference signal (interferogram) into the optical spectrum waveform.

Fast data processing

Analyze the given optical spectrum waveform. Then output the wavelength and power data of the input signal.

Real-time wavelength correction

Correct the measurement error by simultaneously measuring the interference signal of the reference wavelength while measuring the input signal.

Michelson interferometer

AQ9441 Connector Adapter

Suffix Descriptions
-FC FC type
-SC SC type

751535-E3 Rack mounting kit

RACK MOUNTING KIT For an EIA-compliant Single-housing Rack

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