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Absolute Interferometry With a 670 nm External Cavity Diode Laser



Jack A. Stone Jr., Alois Stejskal, Lowell P. Howard


In the last few years there has been much interest in the use of tunable diode lasers for absolute interferometry. Here we report on the use of an external cavity diode laser operating in the visible (λ{approximately} 670 nm) for absolute distance measurements. Under laboratory conditions we achieve better than 1 υm standard uncertainty in distance measurements over a range of 5 m, but significantly larger uncertainties will probably be more typical of practical measurements where conditions are far from ideal. In this paper we analyze the primary sources of uncertainty limiting the performance of wavelength-sweeping techniques for absolute interferometry, and we discuss how errors can be minimized. Many errors are greatly magnified when using the wavelength sweeping technique; sources of error that are normally relevant only at the nanometer level (when using standard interferometric techniques) may be significant here for measurements at the micrometer level.
Applied Optics
No. 28


absolute distance, distance measurement, external cavity laser diode, interferometry, interpolation errors, optical mixing, periodic errors, wavelength shifting, wavelength sweeping


Stone, J. , Stejskal, A. and Howard, L. (1999), Absolute Interferometry With a 670 nm External Cavity Diode Laser, Applied Optics (Accessed April 23, 2024)
Created October 1, 1999, Updated February 19, 2017