We correct a fundamental error occurring in the paper by F. Kahmann [J. Opt. Soc. Am. A10, 1562 (1993)] leading to a different value for the parameter ϕ<sub>p,0</sub>, i.e., the initial phase shift for the complex grating.
© 2006 Optical Society of America
Original Manuscript: December 21, 2005
Manuscript Accepted: April 4, 2006
Martin Fally, "Separate and simultaneous investigation of absorption gratings and refractive-index gratings by beam-coupling analysis: comment," J. Opt. Soc. Am. A 23, 2662-2663 (2006)