This Series Optical Circulators is a three-port device that allows light to travel in only one direction. A signal entering Port 1 will exit Port 2 with minimal loss, while a signal entering Port 2 will exit Port 3 with minimal loss. Light entering port 2 experiences a large amount of loss at port 1, and light entering port 3 experiences a large amount of loss at ports 2 and 1. Optical circulators are non-reciprocal devices. With our proprietary magnetic-optics technology and proven advanced micro-optics design, the circulator features low insertion loss, high isolation, high power handling, and high stability. Optical circulators are widely used in sensor and communication systems. LD-PD INC also provides customized designs to meet special applications.