摘要 |
In a method and an optical switch by which a signal light is accurately switched even if a polarization state of a signal light inputted has a fluctuation, power of an output light of a polarizer which receives a signal light extracted from an output light of a nonlinear optical medium is monitored and a polarization state of an input signal light to the nonlinear optical medium is controlled so that the power becomes minimum (or maximum). The polarization state of the input signal light is monitored, a calculation of performing a predetermined conversion is executed to the polarization state of the input signal light, and a calculated polarization state is recorded (or recorded without conversion). A polarization state of a control light with respect to the input signal light is monitored and the polarization state of the control light is controlled so as to coincide with the polarization state of the input signal light recorded.
|