WAVELENGTH SUPERIMPOSING DEVICE, MANUFACTURING METHOD THEREFOR, AND WDM NETWORK SYSTEM

摘要

A wavelength superimposing device, its manufacturing method and a WDM(Wavelength Division Multiplexing) network system are provided to make broadcast communication with a small amount of loss by reducing a loss of transmission light. A filter device(2) reflects light of some wavelengths of an input wavelength multi-light in a different direction from a light path direction of the corresponding input wavelength multi-light, and allows light of the remaining wavelengths to transmit therethrough. The first optical system makes the reflective light reflected by the filter device(2) made incident again on a plurality of incident positions of a reflection surface of the filter device(2). The second optical system divides the transmission light of the filter device(2) by each wavelength and allows the transmission light made incident on the plurality of incident positions from a transmission surface of the filter device(2).