| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical branching and inserting switch, wherein the scale of a monitor circuit for measuring an optical power is small. <P>SOLUTION: A control circuit 225 stores drive currents I<SB>222</SB>, I<SB>223</SB>of variable optical attenuators 222, 223 and an insertion loss from a through port (ThrIn) to an output port (Out) and from an add port (Add) to the output port by each wavelength, and the control circuit calculates the optical power of a signal light in the through port, the optical power of a signal light in the add port, and the optical power of a signal light with each wavelength at an output of an optical multiplexer 203 on the basis of the optical power measured by a photodetector 227 and the drive currents and the insertion loss stored in the control circuit itself. <P>COPYRIGHT: (C)2007,JPO&INPIT |
