Анализатор оптического спектра OSA 305

Rear-Mounted Hose Connections for Purging and BNC Trigger Connections on the Redstone OSA


The calibration laser can be connected directly to the FC/PC fiber input using the included hybrid patch cable.


FC/PC Fiber Receptacle Behind Door


60 mm Cage Components can be used to couple a free-space beam into the OSA.


The Redstone OSA weighs 58.4 lbs (26.5 kg). Handles are included on the side panels for easy lifting.

• Multi-Detector Configuration for Broad Operation Range: 1.0 - 5.6 µm (10 000 - 1786 cm-1)
• Four Resolution Settings and Three Sensitivity Levels 
• Front Panel Access to Frequency-Locked Laser for Wavelength Calibration
• Two Optical Input Ports
  • FC/PC Fiber-Coupled Input
  • Free-Space Input with Four 4-40 Taps for 60 mm Cage System Compatibility
  • Trigger Input for External Synchronization
  • Built-In Hose Connections for Optional Purging
  • Includes Windows® Laptop and Items Shown in Shipping List Tab 

Thorlabs' Redstone OSA305 Optical Spectrum Analyzer (OSA) measures the optical power of both narrowband and broadband sources as a function of wavelength with higher resolution and a lower noise floor compared to the OSAs sold above. The maximum spectral resolution of 2.0 GHz (0.0625 cm-1) is set by the maximum optical path length difference of 16 cm, as explained in the Design tab, while the high spectral accuracy reaching down to ±0.2 ppm (parts per million) is ensured by simultaneously measuring the interferogram of a frequency-locked 1532.8323 nm alignment laser. For sources with linewidths <10 GHz, the Wavelength Meter mode provides center wavelength measurements with 0.1 ppm resolution and ±0.5 ppm accuracy.

To meet the needs of your specific application, customization options are available for the Redstone OSA; please contact Tech Support for assistance. Common specials for this device include alternative input receptacles, small adjustments to the wavelength range, extra test protocols, and shipping without a laptop.

Resolution and Sensitivity
This high-performance OSA offers four resolution settings that can resolve spectral features 4.0, 1.0, 0.25, or 0.0625 cm-1 apart. Three sensitivity levels are also available, which control the acquisition speed and available gain levels. For detailed specifications on the acquisition update frequency for each sensitivity and resolution setting, please see the Specs tab. 

Calibration Laser
For the Redstone OSA, the internal frequency-locked calibration laser is accessible through the FC/APC fiber output located above the power switch on the front panel. This can be used for wavelength calibration by connecting the front-panel output to the FC/PC fiber input using the included single mode patch cable. During calibration, the software compares the measured wavelength to the reference and performs a calibration if necessary.

Interferogram Averaging
An integrated internal broadband reference source allows the Redstone OSA to accurately determine the location of zero path difference (ZPD) between the two optical branches. The ZPD can be used to average interferograms, which reduces the signal-to-noise ratio. The beam profile overlap between the two branches is optimized using piezoelectric actuators.

Fiber-Coupled and Free-Space Inputs
All of our OSAs directly accept fiber-coupled or free-space optical inputs. The fiber-coupled input is compatible with single mode and multimode FC/PC patch cables. For multimode patch cables made from standard silica glass, cores up to Ø50 µm and NAs up to 0.22 are recommended; for those made from fluoride glass, cores up to Ø100 µm and NAs up to 0.26 are recommended. Single mode patch cables provide the highest contrast. OSAs with other fiber input receptacles are available by contacting Tech Support.

The free-space input aperture accepts collimated input beams with a beam size of up to Ø10 mm, which improves light collection for weak signals as compared to the OSA20xC OSAs. To align the input light with respect to the OSA's internal interferometer, a red, Class 1 alignment beam, which is activated through the OSA software, is emitted from the aperture. The input beam should be made collinear to the alignment beam for the OSA to provide optimal measurement accuracy. For more details on free-space alignment, please see the application note here. Four 4-40 taps around the input aperture enable compatibility with our 60 mm cage system; use cage rods no shorter than 1.5" to prevent attached cage components from clashing with the door. For more information on free-space coupling, please see the Free-Space Coupling tab.

Hose Inlets for Optional Purging
To reduce the presence of water absorption lines in the measured spectrum, our OSAs offer two 1/4" inner diameter quick-connect hose connections on the back panel, through which the interferometer can be purged with dry air. Thorlabs' Pure Air Circulator Unit is ideal for this task. Purging the OSA is not generally necessary, since none of the optics are made from hygroscopic materials, but can be useful for applications such as gas detection and identification where the presence of trace gases in the housing may affect the measurement. An example setup that uses the OSA203C instrument is described in the Gas Spectroscopy tab.

Software
The Redstone OSA includes a Windows® laptop with our OSA software suite version 3.10 pre-installed and a high-speed USB 3.0 cable. This software has a graphical user interface (GUI) that includes a variety of measurement and analysis tools; please see the Software tab for a detailed overview of the software capabilities. To easily interface with the OSAs, an extensive set of drivers are also available for LabVIEW®, C, C++, and C#.