| 摘要 |
PURPOSE:To make possible the detection of troubles in the long optical fiber easily and quickly employing an optical pulse of long wavelength range in which the loss of the fiber can be extremely low using a Q switch Er gas laser. CONSTITUTION:The detector 15 of the optical pulse generator 1 detects the moment at which the switch pulse is generated from the Q switch element 13. The detection output starts the time counter 4 while the laser pulse in the wavelength range of the long optical fiber in which the loss can be extremely low by the Er gas laser 12 is made incident the fiber 5 through the optical coupler 2. The optical detector 3 detects the reflected pulse emitted from the trouble point of the fiber 5 via the coupler 2. The detection signal is applied to the counter 4 to compute the position of trouble in the fiber on the basis of propagation speed of the optical pulse. With such an arrangement, the trouble in the long optical fiber can be detected accurately and easily in the short space of time without split detection or the like. |
