| 摘要 |
PURPOSE:To accuracy detect breakdown or fusing of optical transmission fiber by quiding the CO2 laser beam to the lens, guiding the light beam of the second light source to the fiber and then reflecting the light emitted from the incident edge surface after reflection at the inside of the beam spliter. CONSTITUTION:The CO2 laser beam 1 is converged 2 and then input to the incident edge surface 3a of the optical fiber, then output with the specified diverging angle, then converged 4 and thereby necessary energy density is obtained at the focus O. When the light beam which is different in the wavelength from the CO2 laser is input to the optical axis of fiber 3 from the light source 6 with the specified inclination, the light beam is partly emitted from the edge surface 3b and partly emitted from the incident surface end 3a after reflection. The CO2 laser beam transmits through the beam splitter 8 and only the second light beam is reflected. The reflected beam is converged 9, the detected output 10 is processed 11 and thereby an output of oscillator 1 is controlled. According to this structure, when there is a crack on the optical fiber 3, the light beam of second light source 6 is almost absorbed thereby and amount of reflected light is attenuated and therefore the oscillator 1 is stopped and an alarm 13 is issued. |
