| 摘要 |
PURPOSE: To switch an optical transmission line before an information signal is interrupted. CONSTITUTION: An information signal transmission section 101 and E/O conversion sections 102, 103 of an optical transmitter 100 send an information signal to optical fibers 300, 400 in a synchronized state. An interruption detection signal transmission section 104 and an E/O conversion section 105 send an interruption detection signal to the optical fibers 300, 400 to detect the interruption. A wavelength of the interruption detection signal is set longer than a wavelength of the information signal An optical transmitter 200 is composed of photocouplers 201, 202, fiber delay lines 203, 204, O/E conversion sections 205, 206, 209, 210 and a selector 207, and the selector 207 selects the optical fiber 400 from the optical fiber 300 when the interruption detection signal sent from the optical fiber in use, e.g. the optical fiber 300 is interrupted. |
