Patent ID: 7864330

Claim:
A calibration device for a light intensity measurement device comprising: an optical switch for switching output paths from an optical intensity modulator; a first waveguide being switched by the optical switch; an optical attenuator being provided on the first waveguide; a second waveguide being switched by the optical switch; a light intensity measurement device being connected to the first waveguide and the second waveguide, the light intensity measurement device measuring light intensity of light propagating through the first waveguide or the second waveguide; a control device receiving the light intensity measured by the light intensity measurement device, the control device controlling a signal being applied to the optical intensity modulator; and a signal source receiving control signal from the control device, the signal source adjusting signal being applied to the optical intensity modulator; wherein the control device receives the light intensity measured by the light intensity measurement device, controls signal being applied to the optical intensity modulator and a switching of the optical switch, and wherein the switching of the optical switch is controlled by the control device.