671 Series Laser Wavelength Meter


Highest guaranteed wavelength accuracy

The 671 Laser Wavelength Meter uses proven Michelson interferometer-based design to measure the absolute wavelength of CW lasers. Two versions are available. The model 671A is the most precise, measuring wavelength to an accuracy of ± 0.2 parts per million (± 0.0002 nm at 1000 nm). For experiments that are less exacting, the model 671B is a lower-priced alternative with an accuracy of ± 0.75 parts per million (± 0.0008 nm at 1000 nm). 


Continuous calibration for reliable results

To achieve the reliable accuracy that is expected from Bristol Instruments, the 671 Laser Wavelength Meter is continuously calibrated with a built-in HeNe laser. This is an ideal reference source because its wavelength is well-known and fixed by fundamental atomic structure. To achieve the highest accuracy, the 671A uses a single-frequency HeNe laser that is stabilized using a precise balanced longitudinal mode technique. A standard HeNe laser is used as the wavelength reference in the model 671B. 


Broad wavelength coverage and straightforward operation

The 671 Laser Wavelength Meter is available in four broad wavelength configurations to satisfy virtually any experimental requirement. These ranges are the VIS (375 – 1100 nm), NIR (520 – 1700 nm), IR (1 – 5 μm), and MIR (1.5 – 12 μm). The system operates with a PC, running under windows, via USB or Ethernet. Software is provided to control measurement parameters and to report data, or the system can become part of an experiment using a library of commands for custom or LabVIEW programming. In addition, a web-based application can be used to display or collect measurement data with a tablet or smart phone. 

Reliable accuracy gives you greater confidence in your experimental results from the visible to the mid-IR.

  • Wavelength accuracy as high as ± 0.0001 nm 
  • Continuous calibration with built-in wavelength standard
  • Exceptional repeatability results in wavelength resolution as high as 0.03 pm
  • Operation available from 375 nm to 12 μm
  • Straightforward operation with PC using USB or Ethernet
  • Automatic data reporting using custom or LabVIEW programming eliminates the need for a dedicated PC
  • Convenient tablet/smartphone application reports measurement data anywhere in the laboratory


  • Fiber-Optic Couplers / Adaptors / Patch Cables
  • Convenient options for operation with optical fiber.

  • Fiber-Optic Switch
  • Connect up to eight lasers to the model 671.