Patent ID: 7228021

Claim:
A bidirectional optical add/drop multiplexer comprising: a first optical line having first and second cross points; a second optical line configured to pass the first optical line at the first and second cross points; a first filter disposed at the first cross point and configured to reflect a first optical signal having a pre-selected among input forward optical signals, pass the remaining forward optical signals, and add an optical signal input from a first add terminal to the remaining forward optical signals; a second filter disposed at the second cross point and configured to reflect a second optical signal having a pre-selected among input reverse optical signals, pass the remaining reverse optical signals, and add an optical signal input from a second add terminal to the remaining reverse optical signals; a first optical splitter disposed in the second optical line and configured to output the optical signal from the first add terminal to the first filter, wherein the reflected second optical signal having passed through the first filter is outputted to a second drop terminal; and a second optical splitter disposed in the second optical line and configured to output the optical signal from the second add terminal to the second filter, wherein the reflected first optical signal having passed through the second filter is outputted to a first drop terminal.