# Yokogawa AQ6370D 600 to 1700 nm Optical Spectrum Analyzer (Pre-Owned)

# Yokogawa AQ6370D 600 to 1700 nm Optical Spectrum Analyzer (Pre-Owned)

## Key Features At A Glance

-   Maintenance-free free-space optical input accepts both single-mode and multimode fiber
-   Series spans visible through mid-infrared, from 350 nm to 5500 nm depending on the model
-   Up to 10 wavelength resolution settings and 7 sensitivity settings tune resolution, sensitivity and speed
-   Automatic optical alignment and wavelength calibration via a built-in reference light source (model-dependent)
-   GP-IB, Ethernet and USB remote control with SCPI- and AQ6317-compatible commands plus LabVIEW drivers
-   Up to 16 built-in analysis functions: WDM/OSNR, optical amplifier, DFB-LD, FP-LD/VCSEL, LED, SMSR (varies by model)
-   Built-in cut filter suppresses high-order diffracted light; 10.4-inch 800x600 color LCD display
-   Double-speed sweep mode up to 2x faster with a 2 dB sensitivity penalty

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.

Model

Wavelength Range

Min. Resolution

Level Sensitivity

**AQ6370D**

600 to 1700 nm

0.02 nm

−90 dBm

AQ6373B

350 to 1200 nm

0.01 nm

−80 dBm

AQ6374

350 to 1750 nm

0.05 nm

−80 dBm

AQ6375E

1200 to 2400 nm

0.05 nm

−70 dBm

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

## Product Core & Specifications

Specification

Standard (-12)

High performance (-22)

Optical Specifications

Wavelength range

600 to 1700 nm

600 to 1700 nm

Span

0.1 nm to 1100 nm (Full span), and 0 nm

0.1 nm to 1100 nm (Full span), and 0 nm

Wavelength accuracy

±0.02 nm (1520 to 1580 nm), ±0.02 nm (1580 to 1620 nm), ±0.04 nm (1450 to 1520 nm), ±0.10 nm (Full range)

±0.01 nm (1520 to 1580 nm), ±0.02 nm (1580 to 1620 nm), ±0.04 nm (1450 to 1520 nm), ±0.10 nm (Full range)

Wavelength linearity

±0.01 nm (1520 to 1580 nm), ±0.02 nm (1450 to 1520 nm, 1580 to 1620 nm)

±0.01 nm (1520 to 1580 nm), ±0.02 nm (1450 to 1520 nm, 1580 to 1620 nm)

Wavelength repeatability

±0.005 nm (1 min.)

±0.005 nm (1 min.)

Wavelength resolution setting

0.02, 0.05, 0.1, 0.2, 0.5, 1 and 2 nm

0.02, 0.05, 0.1, 0.2, 0.5, 1 and 2 nm

Wavelength resolution bandwidth accuracy

±5% (1450 to 1620 nm, Resolution setting: ≥ 0.1 nm, after performing the Resolution Calibration function)

±5% (1450 to 1620 nm, Resolution setting: ≥ 0.1 nm, after performing the Resolution Calibration function)

Min. sampling resolution

0.001 nm

0.001 nm

Number of sampling

101 to 50001, AUTO

101 to 50001, AUTO

Level sensitivity setting

NORM\_HOLD, NORM\_AUTO, NORMAL, MID, HIGH1, HIGH2 and HIGH3

NORM\_HOLD, NORM\_AUTO, NORMAL, MID, HIGH1, HIGH2 and HIGH3

High dynamic mode

SWITCH (Sensitivity: MID, HIGH1-3)

SWITCH (Sensitivity: MID, HIGH1-3)

Level sensitivity

−90 dBm (1300 to 1620 nm), −85 dBm (1000 to 1300 nm), −60 dBm (600 to 1000 nm) (Sensitivity: HIGH3)

−90 dBm (1300 to 1620 nm), −85 dBm (1000 to 1300 nm), −60 dBm (600 to 1000 nm) (Sensitivity: HIGH3)

Maximum input power

+20 dBm (Per channel, full range)

+20 dBm (Per channel, full range)

Maximum safe input power

+25 dBm (Total input power)

+25 dBm (Total input power)

Level accuracy

±0.4 dB (1310/1550 nm, Input level: −20 dBm, Sensitivity: MID, HIGH1-3)

±0.4 dB (1310/1550 nm, Input level: −20 dBm, Sensitivity: MID, HIGH1-3)

Level linearity

±0.05 dB (Input level: −50 to +10 dBm, Sensitivity: HIGH1-3)

±0.05 dB (Input level: −50 to +10 dBm, Sensitivity: HIGH1-3)

Level flatness

±0.1 dB (1520 to 1580 nm), ±0.2 dB (1450 to 1520 nm, 1580 to 1620 nm)

±0.1 dB (1520 to 1580 nm), ±0.2 dB (1450 to 1520 nm, 1580 to 1620 nm)

Polarization dependence

±0.05 dB (1550/1600 nm), ±0.08 dB (1310 nm)

±0.05 dB (1550/1600 nm), ±0.08 dB (1310 nm)

Dynamic range (Resolution: 0.02 nm)

55 dB (Peak ±0.2 nm), 37 dB (Peak ±0.1 nm)

58 dB (Peak ±0.2 nm, 60 dB typ.), 45 dB (Peak ±0.1 nm, 50 dB typ.)

Dynamic range (Resolution: 0.05 nm)

73 dB (Peak ±1.0 nm), 62 dB (Peak ±0.4 nm), 45 dB (Peak ±0.2 nm)

73 dB (Peak ±1.0 nm, 78 dB typ.), 64 dB (Peak ±0.4 nm, 70 dB typ.), 50 dB (Peak ±0.2 nm, 55 dB typ.)

Dynamic range (Resolution: 0.1 nm)

57 dB (Peak ±0.4 nm), 40 dB (Peak ±0.2 nm)

60 dB (Peak ±0.4 nm, 67 dB typ.), 45 dB (Peak ±0.2 nm, 50 dB typ.)

Stray-light suppression ratio

73 dB

76 dB (80 dB typ.)

Optical return loss

35 dB typ. (with angled-PC connector)

35 dB typ. (with angled-PC connector)

Applicable fiber

SM (9.5/125), MM (GI 50/125, GI 62.5/125, Large core: up to 200 µm)

SM (9.5/125), MM (GI 50/125, GI 62.5/125, Large core: up to 200 µm)

Optical connector

Optical input: AQ9447 Connector adapter (option) required. Calibration output: AQ9441 Connector adapter (option) required. Connector type FC or SC

Optical input: AQ9447 Connector adapter (option) required. Calibration output: AQ9441 Connector adapter (option) required. Connector type FC or SC

Built-in calibration light source

Wavelength reference source (option)

Wavelength reference source (option)

Sweep time

NORM\_AUTO: 0.2 s, NORMAL: 1 s, MID: 2 s, HIGH1: 5 s, HIGH2: 20 s, HIGH3: 75 s

NORM\_AUTO: 0.2 s, NORMAL: 1 s, MID: 2 s, HIGH1: 5 s, HIGH2: 20 s, HIGH3: 75 s

Warm-up time

Minimum 1 hour

Minimum 1 hour

> **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.**

## Details

- **Price:** 0.0 USD - 1365.0 USD
- **Vendor:** Yokogawa
- **Type:** Opt Ana
- **Tags:** Analyzers, AQ6370, AQ6370D, Manufacturers, Model 6370, Optical, Optical Spectrum Analyzer, Pre-Owned, product_manual_group_2, Product_used, Yokogawa, Yokogawa Test & Measurement Corporation

## Variants

| Variant | Price | Available |
|---------|-------|-----------|
| None | 0.00 USD | In stock |
| Standard Calibration | 1365.00 USD | In stock |

## Images

- Yokogawa AQ6370D 600 to 1700 nm Optical Spectrum Analyzer (Pre-Owned)

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> Source: [ValueTronics](https://valuetronics.com/products/aq6370d-yokogawa-optical-analyzer-used)
> Updated: 2026-06-02
