Abstract

Thin-film filters are widely used in wavelength add/drop modules as a cost-effective approach for relatively low (1–16) channel counts. They are traditionally packaged in three-port devices consisting of a collimating lens, thin-film filter, and a focusing lens. The packaged device has input and upgrade ports on one end and the add/drop port on the other. Modules of these devices can then be fabricated by connecting such three-port devices with fibers.

© 2002 Optical Society of America