Fiber optic cross connect with transparent substrate

Abstract

The present invention provides an improved fiber optic cross connect (OXC) package. The OXC includes a substrate, where light beams may travel through the substrate; a plurality of optical fibers optically coupled to a first surface of the substrate; and a micromirror array coupled to a second surface of the substrate. In the preferred embodiment, this substrate is optically transparent to the wavelengths of interest. The light beams enter the substrate from one surface, traverses the substrate, and exits from an opposite surface of the substrate. The opposite surface is populated with micromirrors. By folding the light beams in a switch architecture with the substrate, the size of the switch package is reduced. Using the substrate in combination with a modular approach to substrate population allows for a single die switch with a higher die yield and scalability. Integrated circuits may be placed on the same substrate as the micromirrors, and the complexity of the assembly process is reduced. With the addition of the second cap, the light beam is folded during the switching operation, resulting in a smaller switch package.