| 摘要 |
An optical add/drop circuit including a first optical circulator 10 having three ports 10A, 10B, 10C, a first fibre grating 12, a second optical circulator 18 having three ports 18A, 18B, 18C, a second fibre grating 16, and an optical isolator 14 connecting the two fibre gratings 10,18. First input light having a wavelength # 10 and second input light having a wavelength # 20 are supplied to port 10A. Port 10B outputs the first input light (reflected from the first grating 12) as drop light. The second input light is output from port 10B, passes through the first grating 12, the optical isolator 14 and the second fibre grating 16 and reaches port 18A. Add light having a wavelength # 10 is supplied to port 18C. Port 18B outputs this add light (reflected from the second grating 16) and the second input light. This optical add/drop circuit is stable in operation because resonance or the like is prevented. |
