The AQ6370D is the telecom-focused member of Yokogawa's AQ6370 Series of optical spectrum analyzers. An optical spectrum analyzer measures how optical power is distributed across wavelength, letting an engineer characterize the spectral content of a light source, fiber, or photonic device. The AQ6370 Series is built around an advanced free-space grating monochromator and is presented as the product of more than 40 years of optical-testing experience, designed to measure the performance of photonic devices and systems across a wide range of applications.

Yokogawa lists a broad set of applications for the AQ6370 Series. These include WDM OSNR testing of DWDM transmission systems, optical amplifier (EDFA-NF) characterization, optical transceiver and LD-module testing, and characterization of laser sources such as DFB-LD, FP-LD and VCSEL. The series is also applied to characterization of supercontinuum light sources, visible LED measurement, passive-component testing of WDM filters, FBGs, ROADMs and WSS devices, loss-wavelength characterization of optical fibers, gas detection and concentration measurement, and characterization of sources used in laser absorption spectroscopy. Beyond telecommunications, the series addresses photonics in industrial manufacturing, biological studies, healthcare, lighting, imaging, and sensing for safety, security and environmental pollution control.

ValueTronics stocks test-and-measurement instruments in its own 20,000 sq ft secure warehouse at 1675 Cambridge Drive in Elgin, Illinois. Every pre-owned unit is sourced and fulfilled directly from that inventory. Each pre-owned unit is inspected and functionally verified in-house before it ships, while new units ship factory-sealed exactly as received from the manufacturer.

Brand Heritage

In 2002, Yokogawa became a leading supplier of optical spectrum analyzers following its acquisition of Ando Electric, consolidating that optical-testing expertise under the Yokogawa name.

Compare Other Models in This Series

The AQ6370 Series is a family of free-space-monochromator optical spectrum analyzers that share a common platform but cover different wavelength ranges, so that R&D and manufacturing centers in any industry can select the model matched to the photonic devices and systems they test. Each model is specifically designed to accurately and quickly measure spectral performance within its own range.

The models span the visible region through the mid-infrared: the AQ6370D covers 600 to 1700 nm for telecom devices, the AQ6373B covers 350 to 1200 nm for visible-light measurement, and the AQ6374 covers 350 to 1750 nm including both visible and communications wavelengths. The AQ6375E covers the SWIR region (1200 to 2400 nm, with an extended 1000 to 2500 nm option), while the AQ6376E covers 1500 to 3400 nm and the AQ6377 covers 1900 to 5500 nm in the MWIR region used for environmental sensing and medical applications.

Each model below links to its own dedicated product page with condition-matched pricing for the pre-owned configuration. Select the model whose wavelength range and performance match your application, then choose the condition and options on that model's page.

Within the family, the AQ6370D is positioned for optical-communication R&D and production. It offers a wide close-in dynamic range of 78 dB typical, high wavelength accuracy of +/-0.01 nm (high-performance model, 1520 to 1580 nm), and fast measurement of only 0.2 s for a 100 nm span at NORM_AUTO. Yokogawa identifies it as the first OSA to guarantee a stray-light suppression ratio specification, and it adds Littrow light cancellation, an APC connector level-correction function, a gate sampling function for recirculating-loop testing, and a resolution calibration function.

Beyond wavelength range, the models differ in sensitivity, dynamic range, resolution settings and connector style as detailed in the comparison table. Level sensitivity reaches -90 dBm on the AQ6370D, while the long-wavelength models specify ranges such as -80 dBm on the AQ6373B and AQ6374, -70 dBm on the AQ6375E, -65 dBm on the AQ6376E and -60 dBm on the AQ6377. Close-in dynamic range likewise varies, from 78 dB typical on the AQ6370D down to 50 dB on the AQ6377.

Feature availability also differs across the family. A gas-purge feature for reducing water-vapor absorption is built into the AQ6374, AQ6375E, AQ6376E and AQ6377; a multi-touch touchscreen and pre-installed DUT-oriented test apps are provided on the AQ6375E and AQ6376E; and a built-in wavelength reference source is fitted to every model except the AQ6373B, which requires an external reference source for wavelength calibration. Color analysis is available on the AQ6373B and AQ6374. Refer to the comparison table for each model's specific resolution settings, dynamic range and applicable fiber.

Additional differences in specifications beyond the few shown above are not listed here — see each model's full specifications below.

Product Core & Specifications

Important: A minimum 1-hour warm-up is required, after which optical alignment must be performed.

Important: For the AQ6370D and AQ6374, an optical connector adapter is required and ordered as an option (not included): AQ9447 connector adapter for the optical input port and AQ9441 connector adapter for the calibration output port (FC or SC type).

Important: The AQ6373B requires an external reference source for wavelength calibration; it is equipped only with an optical alignment source and a built-in wavelength reference source is not provided.

Important: This is a Class A instrument based on Emission standards EN 61326-1 and EN 55011 and is designed for an industrial environment. Operation of this equipment in a residential area may cause radio interference, in which case users will be responsible for any interference which they cause.

Important: Specifications are guaranteed only when a single mode fiber in which light travels in single mode at the measured wavelength is used; when the measured wavelength is below the cut-off wavelength of the used fiber, or a multimode fiber is used, the measured spectrum may be inaccurate due to speckle noise (caution especially for high-coherency sources such as gas lasers and laser diodes).

Recommended pairing: the AQ2200 Series Multi-Application Test System (MATS) supplies the multiplexed laser sources and attenuator used in the optical amplifier (EDFA-NF) test setup.

About this Pre-Owned unit

This pre-owned unit is inspected and functionally verified in-house before it ships and is backed by our pre-owned warranty. To confirm its exact condition, firmware revision, installed options, or included accessories for your application before ordering, contact our Test Architects.

• Warranty included
• Functional verification included
• Standard Calibration Upgrade Options: No Calibration Required, NIST Traceable, Z540.1 or ISO 17025 with Data, Z540.3 Guardbanding with Data.
• Note that unnecessary accessories may not be included (contact Test Architect to confirm).

ValueTronics supplies both new and used test and measurement equipment. New units ship factory-sealed, exactly as received from the manufacturer; every used unit is inspected and functionally verified in-house at our 20,000 sq ft secure facility in Elgin, Illinois before it ships. Our Test Architects can help you select the condition, calibration, and configuration that fit your application.

Please review the Manufacturer's Data Sheet to verify published specifications. Feedback on this webpage is always welcome — please reach out to your Test Architect at any time for questions or concerns. Thank you, we truly appreciate you being our customer.