Visible Wavelength Optical Spectrum Analyzer AQ6373 (DISCONTINUED)

Notice: This product was discontinued on Apr 30, 2015. See this replacement product:

The AQ6373 is one of the latest additions to the AQ6370 Series of Optical Spectrum Analyzers. With the ability to provide high speed, accurate analysis of the short wavelength range between 350nm and 1200nm, this OSA is well suited for a broad range of applications. The AQ6373 can accelerate the development and manufacturing of short wavelength lasers, passive devices and LEDs as well as equipment that uses these devices for the biomedical, material processing, consumer product and telecommunications markets. With built in color analysis capabilities and remote command compatibility with the AQ6315, the AQ6373 provides an upgrade of capabilities, speed and performance for current AQ6315 users.

  • Wavelength range: 350 to 1200nm
  • Wavelength accuracy: ±0.05 nm
  • Wavelength resolution: 0.02 to 10 nm and 0.01nm (400 to 470nm)
  • Max safe input power: +20 dBm
  • Level sensitivity: -80 dBm
  • Dynamic range: ≧60dB
  • Single-mode, Multimode, and Large-core fibers
  • Built-in optical alignment source
  • Wavelength calibration with an external reference source
  • Various analysis functions including the Color analysis function for VIS

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  • Optical active devices(Laser diode/Fiber laser)
  • Optical passive devices(Filter/FBG/Specialty optical fiber)
  • Development support of Applied photonics equipment


  • Medical/Bio: Laser therapy, DNA sequencing, Microscope
  • Industrial: Laser micro-machine, laser maker
  • Home Electronics: Laser projector, Next-gen optical disc, LED products
  • Measurement Sensing: LIDAR, Interferometer
  • Telecom: Plastic Optical fiber (POF) communication

World-class optical performance

High Resolution & High Dynamic Range
The advanced monochromator achieves high wavelength resolution and high close-in dynamic range. With the sharper spectral characteristics of the monochromator, spectral signals in close proximity can be separated clearly and measured accurately.
High Sensitivity
Weak optical signals can be measured accurately and quickly.



  7 sensitivity settings
Can be selected according to test applications and measurement speed requirements.
  High dynamic mode
Obtains a better dynamic range by reducing the influence of stray-light, which is caused when the input is a strong optical signal.

Pulsed Light Measurement




  Peak-Hold and External trigger mode
Measure a pulse peak spectrum of a pulsed light signal. Often used in the transmission loop testing of telecommunication systems, and also in the low power measurement at the early stage of laser chip development to catch the peak power of a pulsed signal. 

Free Space Input



  ■Multimode and single mode fiber on the same OSA

■Small insertion loss variation at the input connector increases measurement repeatability.

■No damage connecting fibers because there is no physical contact.

■Supports SM, GI (50/125 μm, 62.5/125 μm) and large core fiber up to 800 μm. 
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Excellent efficiency


Fast SweepWith an advanced monochromator, faster electrical circuits, and noise reduction techniques, the AQ6373 achieves fast measurement speed even when measuring a steep spectrum from DFB-LD or DWDM signals, or when measuring a low power signal from a broadband light source.

Fast Remote Interface
    AQ6373 provides faster remote control and data transfer capability.
   100x    Ethernet interface is 100 times faster
     10x     GP-IB interface is  10 times faster
(compared with the conventional GP-IB used on Yokogawa AQ6317 series Optical Spectrum Analyzer)

Wide Span Sweep yet High Resolution
The 50,001 data sampling points expands measurement range in a single sweep while keeping a high wavelength resolution. This makes your measurements easier and more efficient than conventional systems that use a low number of sampling points and require multiple partial measurements to cover the complete wavelength range.



Easy to Keep Accurate

Ambient condition change, vibration and shock to an optical precision product, like an optical spectrum analyzer, will effect the optical components and eventually degrade optical performance.
Using standard functions, the AQ6373 can maintain its high optical performance within a couple of minutes so that you can quickly start a measurement.

Optical alignment function
 Automatically aligns the optical path in the monochromator using the built-in source to maintain high performance.
Wavelength calibration function
 Automatically calibrates the spectrum analyzer with an external light source, to ensure the wavelength accuracy.




  Built-in optical alignment source
Note. GI 50/125µm fiber is required.
An external light source is required for the wavelength calibration.

Note. There are cases that the optical alignment and wavelength calibration function cannot correct optical performance.
Periodical calibration is also required.



USB ports

  • Mouse
  • Keyboard
  • Memory
  • HDD

Easy Operation

Trace zooming


■Change display conditions, such as center wavelength and span, by clicking and dragging the mouse.
■Enlarge your area of interest instantly and  move it at will.
■No need for another measurement to modify the display conditions.
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Mouse & Keyboard operation

■Front panel operation proven intuitive and easy to use by our many of users.
■Even easier with a mouse.
■The keyboard helps enter labels and file names.
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Easy Data handling


■USB storage
-USB 1.1 compatible interfaces support large size removable memory devices  such as Flash ROM and hard disk drives (HDD).
- Easy way to carry a large number of data files.

■128MB Internal storage
- Save over 5,000 data files

File types and formats:
- Trace: Binary and ASCII (CSV)
- Graphic: Bitmap (BMP) and TIFF
- Analysis results: Binary and ASCII (CSV)   
- Template: ASCII (CSV)
- System setup: Binary   
- Macro program: Binary
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Thumbnail  File Preview
Easy to find a particular file out of thousands of files in internal and external storage.
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Various Analysis Functions

Spectrum analysis functions
13+ data analysis functions for popular applications

■Built-in analysis functions:     - Spectral width analysis
    - WDM (OSNR) analysis
    - DFB-LD analysis
    - FP-LD analysis
    - LED analysis
    - SMSR analysis
    - Optical power analysis
    - Various filter analysis
    - Color analysis
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7 individual traces

■Calculation between traces (subtraction between traces

■Max/Min hold

■Simultaneous multi-trace display

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Building Automated Test System

Macro programming




Build a simple auto-measurement system

■No external PC is required.

■Easy to create test program by recording the user’s actual key strokes and parameter selections.

■Can control external equipment through the remote interfaces.
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Fast remote interfaces




■GP-IB, RS-232, and Ethernet (10/100Base-T) interfaces
 Easy to control with an external PC and to build an automated test system.

■Improve the testing throughput of test systems
by the fast measurement, command processing, and data transfer speed.

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SCPI compatible
The standard remote commands are compatible with SCPI, which is an ASCII text based standard code and format that conforms to IEEE-488.2.

AQ6317 Emulation mode
Supports the private remote commands of Yokogawa's best selling AQ6317 series and AQ6315 for users to easily upgrade from their current automated test environment.
Note. some commands may not be compatible due to changes in specifications and functions.

LabVIEW® driver available


■Visible LED Test
The optical spectrum of visible LEDs used in lighting, indication, measurement and applications can be measured and analyzed.


By supporting the large core fiber input, the AQ6373 can efficiently get the LED light and measure its spectrum. The built-in color analysis function automatically evaluates a dominant wavelength and chromatic coordinates.


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In conjunction with a white light source, an ASE light source or other broadband
light source, you can simply perform evaluation of passive devices such as WDM
filters and FBG. The AQ6373's superb optical characteristics enable higherresolution
and wider dynamic range measurements.
The built-in optical filter analysis function simultaneously reports peak/bottom
wavelength, level, crosstalk, and ripple width.

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NA Conversion Adapter

  • 735383-A001, A002 numerical aperture conversion adapters
  • Half numerical aperture of optical fiber 
  • AQ6370 series optical spectrum analyzers' free-space optical input structure 

For the AQ6373 Optical Spectrum Analyzer you can use a maximum 800 micron core fiber that must be terminated in a standard FC connector.   For the AQ6375 and AQ6370 series OSA you can use a maximum 200 micron core fiber which, ...

  • It is possible to convert an AQ6370 Optical Spectrum Analyzer Binary file to ASCII .CSV file using the AQ6370 Viewer Software? 
  • Different AQ637X series OSA Viewer software will load specific binary file extensions.

The AQ6370C Optical Spectrum Analyzer was developed in accordance with the IEC standard: WG4 (IEC 61280-1-3) Test procedures for general communication subsystems -Central wavelength and spectral width measurement. We cannot guarantee the RMS ...


The AQ6373 optical spectrum analyzer performs the color analysis function as follows:1. Measure the spectrum 2. Compare the measured spectrum with “color matching functions”  as defined by the CIE Using these ...


Level Accuracy:Level Accuracy is a tolerance to the true value of measured value, when a standard level is measured with a standard wavelength. Level Linearity:Level Linearity is the width of error dispersion ...


Wavelength accuracy: Wavelength accuracy is a tolerance to the true value of a measured value when the standard wavelength is measured.  Wavelength repeatability:Wavelength repeatability is the stability of ...


Yes, the AQ6370 Optical Spectrum Analyzer Viewer Software is compatible with Windows 7 32-bit and 64-bit. Note: Please make sure the correct USB driver is installed for either Windows 7 32-bit or 64-bit.


If the AQ637X series Optical Spectrum Analyzer is already running and you attempt to connect an external display, the OSA will not automatically detect the external display. The OSA will need to be re-booted before it can recognize and ...


The AQ637X Optical Spectrum Analyzer has a feature called Auto Offset that it performs every 10 minutes. What this feature does is zero out the OP amps in the OSA to ensure constant level accuracy. This feature will however, stop the OSA ...


No, unfortunately due to the number of current fiber combinations, we do not stock optical fibers. There are many companies that specialize in optical fiber cords.


The resolution is controlled by 3 factors: Input Slit Detraction Grating  Output Slit The resolution setting controls the output slit disk. This disk has a fixed number of slits in it. Since the setting only control ...


If you are performing wavelength calibration using the instrument's built-in light source, the warning message is an indication that the monochromator needs to be repaired. Please visit our Contact site to locate ...

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