| 摘要 |
PURPOSE:To suppress crosstalk between signal lights and to make a wavelength interval narrow by selecting a wavelength interval between output lights of an optical transmitter to be smaller than a minimum wavelength interval obtained by an optical branching means and making polarized directions of output lights of adjacent wavelengths nearly orthogonal to each other. CONSTITUTION:Two signal lights lambdai, lambdai+1 set at a smaller wavelength interval than a minimum permissible wavelength interval DELTAlambda0 decided by an optical branch means 5 are nearly subject to orthogonal control by polarized light control means 2-i, 2-(i+1) and the resulting signals are sent. When the one signal light lambdai in both signals is received by an optical receiver 7-i, since the wavelength interval (DELTAlambdai+1, i) of both signal lights is smaller than the minimum permissible wavelength interval DELTAlambda0 of the means 5, part of the signal light lambdai+1 is inputted to a polarized light separate means 6-i from the means 5 together with a receiver side signal light lambdai. Since the signal lights lambdai, lambdai+1 nearly have an orthogonal relation and only the component light in parallel with the signal light lambdai received by the means 6-i is extracted separately, the signal light lambdai+1 is eliminated. Thus, only the signal light lambdai reaches an optical receiver 7-i to suppress crosstalk. |
