摘要 |
PROBLEM TO BE SOLVED: To perform wavelength conversion to an arbitrary wavelength band without generating the crosstalk between input wavelength channels in a wavelength band unit including one or a plurality of the wavelength channels. SOLUTION: The arbitrary wavelength conversion circuit for converting the wavelengths of the wavelength band Bi ((i) is an integer from 1 to M) to the arbitrary wavelength bands B1 to BM has the wavelength conversion units cascade-connected to N stages (2N>=M, N is a natural number) and driving circuits for discretely driving and controlling the respective wavelength conversion units. The respective wavelength conversion units perform wavelength conversion to 2N arbitrary wavelength bands according to the 2N combinations of driving/non-driving of the wavelength conversion units by outputting the prescribed wavelength conversion light to each of input signal light during driving and allowing the passage of each of the input signal light during non- driving and output the wavelength conversion light of any among the wavelength bands B1 to BM for the signal light of the wavelength band B1 from the wavelength conversion unit of the final stage. |