Patent ID: 8111989

Claim:
An optical switch, comprising: a first reversible optical circulator, having four I/O ports, wherein the four I/O ports are respectively a first terminal, a second terminal, a third terminal, and a fourth terminal, the four terminals sequentially transmit an optical signal in a forward circulation or a backward circulation according to a first control signal, and an open end is formed between the first terminal and the adjacent fourth terminal; and a second reversible optical circulator, having four I/O ports, wherein the four I/O ports are respectively a first terminal, a second terminal, a third terminal, and a fourth terminal, the four terminals sequentially transmit an optical signal in a forward circulation or a backward circulation according to a second control signal, and an open end is formed between the first terminal and the adjacent fourth terminal, wherein the two open ends of the first reversible optical circulator and the second reversible optical circulator are coupled with each other.