We introduce a Fabry–Perot cavity-length modulation technique for measuring the linewidth of a continuous wave (cw) laser. We calculate the peak intensity of a cw laser transmitted through a Fabry–Perot cavity as a function of mirror speed. By fitting the experimental data to the results of the calculation, we determine the linewidth of a frequency-stabilized cw laser. The linewidth of a cw ring dye laser measured in the 570–590-nm wavelength range is ~170 ∓ 20 kHz. We also demonstrate the use of this technique to measure the reflectivity of a high-reflectance mirror.
© 1999 Optical Society of America
(120.2230) Instrumentation, measurement, and metrology : Fabry-Perot
(120.5700) Instrumentation, measurement, and metrology : Reflection
(140.3570) Lasers and laser optics : Lasers, single-mode
(290.3700) Scattering : Linewidth
(300.6360) Spectroscopy : Spectroscopy, laser
Jae Wan Kim, Jae Won Hahn, Yong Shim Yoo, Jae Yong Lee, Hong Jin Kong, and Hai-Woong Lee, "Measurement of the Linewidth of a Continuous-wave Laser with a Cavity-length Modulation Technique," Appl. Opt. 38, 1742-1745 (1999)