Characterization of Exfo Burleigh products was inaccurate
The article "Solid State Etalons Improve Wavelength Measurement" (June 2004, p. 143) contains several factual errors that your readers should be made aware of.
The article makes a reference to the wavelength meters manufactured by Exfo Burleigh Products Group (without indicating that "Wavemeter" is a trademark of Exfo Burleigh Products) and states that "the minimum laser power required is in the milliwatt range." In fact, our Wavemeter wavelength meters have minimum sensitivities as low as 100 nanowatts. The next statement, "moving components within the interferometer arm necessitated elaborate mechanical and optical isolation . . . from the actual experiment" is unfounded, since our instruments require no such special arrangement and allow the user the choice of a free beam or fiberoptic input without any concerns regarding what takes place inside the instrument.
The next paragraph states that, "More recently WLMs based on solid-state etalons have taken the technological lead . . ." without making any reference to the Fizeau/Fabry-Perot etalon Pulsed Wavemeter technology commercialized by Burleigh more than 15 years ago. Exfo Burleigh Products continues to manufacture and sell the most complete line of high-accuracy laser-wavelength-measurement and spectral-characterization instruments in the world.
Exfo Burleigh Products Group