| 摘要 |
PURPOSE:To measure the loss of connection while considering directivity by making optical pulses incidence to an optical fiber including connection points and by measuring the power of reflected pulses from the terminal surface of the optical fiber before and after connection. CONSTITUTION:The power P7 of optical pulses from the terminal of an optical fiber 2 is measured by an optical-pulse detection part 10. Then when the transmittivity of an optical powder when an optical beam is emitted from the fiber 2 to the air is gamma and the reflectivity of a half-mirror 8 is beta, P7=P1gamma<2>(1-gamma)beta. An optical fiber 3 is conneced to the optical fiber 2 and a light power P13 of optical pulses from the terminal surface of the optical fiber 2 is measured by an optical-pulse detector 10. Then when the optical transmittivity from the fiber 2 to the fiber 3 and that from the fiber 3 to the fiber 2 are t1 and t2, P13= P1gamma<2>(1-gamma)t1t2beta. Therefore, P13/P7=t1t2, so alpha1=(-10/2)log10P13/P7, where alpha1 is the mean bilateral connection loss of the connection point between the optical fibers 2 and 3. For this purpose, P7 and P13 are measured to obtain the connection loss while considering the directivity. |
