Mieko Yamagaki, Sugio Wako, Satoru Abe, Daeyoul Yoon and Hiroshi Matsuura
In recent years wavelength-division multiplexing (WDM) technology has been adopted in configuring large-capacity long-haul fiber-optic communications networks, and bandwidths are becoming narrower in an effort to obtain higher densities on communication wavelengths. This has led to a need for interleaving filters, which from a single input can demultiplex alternate wavelengths to separate outputs. By developing a proprietary configuration, the authors have succeeded in developing an optical interleaving filter that does not require temperature control. This paper describes the configuration of the module, and reports on the properties of prototypes that were fabricated.