Integrated optics is a generic term used to describe guided wave devices combining several functions on a single substrate. Passive integrated optics, or "planar", refers to a family of devices that requires no external power source to perform their functions. Their most promising short-term application is fiber-based telecommunications systems. Examples are power splitters and wavelength division multiplexers (WDMs). For the purposes of this review, we will consider devices in which light enters and exits via optical fiber pigtails.
Couplers will play an important role in the deployment of fiber-in-the-loop (FITL) systems. Corning is currently using a planar integrated optics technology to manufacture couplers that are well-suited for FITL applications.
Passive optical networks (PON) potentially may require optical splitting ratios ranging from 1x2 to 1x32, the maximum spilt recommended by Beilcore SR 1681. In anticipation of this, Corning has developed a monoilthic 1x16 single-mode splitter that offers significant performance advantages for PON using the same integrated-optics in glass technology that currently produces 1x2, 1x4 and 1x8 devices. This paper will review the performance characteristics of lxN planar spiltters, including the new Ix 16. Additionally, preliminary results will be shown for developmental 2xN devices.