| 摘要 |
<P>PROBLEM TO BE SOLVED: To suppress relaxation oscillation of input optical signal strength, and accurately measure the threshold. <P>SOLUTION: A threshold measuring apparatus 1 is provided with an optical attenuator 3 which attenuates an optical signal of fixed strength from an optical source 2, and inputs into an optical module circuit 6. Moreover, a multimeter 8 which detects an output optical signal, is connected to an output terminal of the optical module circuit 6. A control device 9 controls the optical attenuator 3 and the multimeter 8, and measures a lower threshold Pt1 and an upper threshold Pt2 of the optical module circuit 6 using a two division method. Moreover, when input optical signal strength is changed to a mean value Pmid by the two division method, the control device 9 gradually changes an attenuation amount of the optical attenuator 3 in a step. Thereby, it is possible to suppress the relaxation oscillation of the input optical signal strength. <P>COPYRIGHT: (C)2009,JPO&INPIT |
