Patent ID: 7239773

Claim:
An optical-switch testing apparatus that includes a plurality of input ports and output ports, and carries out a test on optical characteristics of an optical switch that deflects a light path for switching optical signals between an input port and an output port corresponding to an arbitrary pass, the optical-switch testing apparatus comprising: a light source that inputs an optical signal for the test to each of the input ports; a light detector that detects a light receiving level of the optical signal output from each of the output ports; and a control unit that, whenever the optical signal is switched, changes a deflection status of the light path to obtain an optimal point at which the light receiving level is maximum, and calculates a parameter to optimize the deflection status based on the optimal point, wherein: the optical switch further comprises: a first mirror array that includes a number of first tilt mirrors corresponding to a number of the input ports and a first deflecting unit that drives the second tilt mirrors to reflect an optical signal incident from an input port in a direction of a first arbitrary angle; and a second mirror array that includes a number of second tilt mirrors corresponding to a number of the output ports and a second deflecting unit that drives the second tilt mirrors to reflect the optical signals incident from the first mirror array in a direction of a second arbitrary angle to the output ports; and the control unit calculates deflection control amounts for changing angles of the first and the second tilt mirrors in order to form light paths between the input port and the output port selected when the optical signal is switched, and supplies the deflection control amounts to the first deflecting unit and the second deflecting unit, respectively; and further comprises: a deflection-control-amount changing unit that changes the deflection control amounts, and supplies the changed deflection control amounts to the first deflecting unit and the second deflecting unit, respectively; an offset calculating unit that, when a light path of a through pass in which a port number of the input port is same as that of the output port is formed, calculates an optical offset of the first mirror array and the second mirror array based on an angle position of an optimal point; and a deflection-control-amount calculating unit that calculates the deflection control amounts for changing angles of the first and second tilt mirrors, respectively of the input ports and the output ports, based on the calculated optical offset.