Thin-film filters used for dense wavelength division multiplexing (DWDM) applications are processed by a variety of deposition techniques, including ion-beam sputtering. Ion-beam sputtering produces high-quality coatings and provides flexibility of coating materials. However, DWDM filters consisting of oxide films that are reactively deposited by ion-beam sputtering, as in most sputter techniques, typically exhibit high levels of compressive stress. This affects the optical characteristics of the filters. Details of the filter passband characteristics and wave-front distortion illustrate the influence of the stress. Spatial variation of the stress on the filter surface causes the filter center wavelength to have spatial variation, and it causes the filter to have an asymmetric passband characteristic.
© 2004 Optical Society of America
(060.0060) Fiber optics and optical communications : Fiber optics and optical communications
(060.1810) Fiber optics and optical communications : Buffers, couplers, routers, switches, and multiplexers
(310.1860) Thin films : Deposition and fabrication
(310.6860) Thin films : Thin films, optical properties
(310.6870) Thin films : Thin films, other properties
Steven L. Prins, Alan C. Barron, William C. Herrmann, and John R. McNeil, "Effect of Stress on Performance of Dense Wavelength Division Multiplexing Filters: Optical Properties," Appl. Opt. 43, 626-632 (2004)