Angle-tuned etalon filters for optical channel selection in high density wavelength division multiplexed systems

Applications are discussed for angle-tuned in-line Fabry-Perot etalons for optical channel selection in a high-density wavelength division multiplexed (WDM) direct-detection fiber system. A typical WDM application (LAMBDANET type) was described. Different demultiplexing techniques and their relative advantages were considered. Design guidelines are given for determining the etalon parameters, the minimum channel spacing and the maximum number of channels for a single etalon and multiple etalons, including stacked identical etalons and stacked nonidentical etalons. Experimental results on using these etalons for optical channel tuning in a multiwavelength WDM optical communication system are presented.<>