Patent ID: 7440649

Claim:
A wavelength selective switch module for splitting wavelength multiplexed light for each wavelength, supplying each wavelength light into a deflection unit, and outputting each wavelength light to one of a plurality of output ports by setting a deflection control amount for the deflection unit, the wavelength selective switch module comprising: a test light generation unit configured to generate test light; a multiplexing unit configured to multiplex the test light with the wavelength multiplexed light; a splitting unit configured to split the test light from output light of each of two output ports of the plurality of output ports; a feedback control unit configured to perform feedback control for obtaining deflection control amounts for the deflection unit corresponding to a wavelength of the test light such that a light level of the test light that is split from the output light output from each of the two output ports becomes maximum; and a deflection control amount calculation unit configured to calculate deflection control amounts for output ports other than the two output ports for the deflection unit for the wavelength of the test light and calculate deflection control amounts for output ports for deflection units of wavelengths included in the wavelength multiplexed light using the deflection control amounts for the deflection unit for the wavelength of the test light output from each of the two output ports by which the light level of the test light becomes maximum.