Showing papers by "Finisar published in 1989"

2×2 Optical bypass switch

Abstract: An optical switch channels incoming light to selected transmission elements. The switch includes a GRIN lens having two opposite surfaces, one of which has a mirror coating applied to it. At least four optical transmission elements, typically optical fibers, are connected to the non-mirrored surface of the lens. When used in an optical signal networking application, one of the four transmission elements couples the switch to a node's receiver and another couples the switch to a node's transmitter. The remaining two transmission elements, called in the input line and the output line, attach the node to the network and thereby conduct light from the previous node to the device or conduct light from the device to the next node on the network. The transmission elements and the lens element move with respect to each other into one of two possible states, called the bypass and active states. In the bypass state, the input line is coupled to the output line so that light from the previous node in the network is transmitted onto the next node, and the node's receiving line is coupled to the node's transmission line so that light from the node transmitter is transmitted back to the node's receiver. In the active state, the switch couples light arriving on the input line, from the previous node, to the node's receiver while simultaneously coupling the node's transmitter to the output line, which carries signals to the next node in the network.