the method described in fig5 was introduced in such a method where the individual dispersion compensation elements are cascaded the coupling loss can rapidly increase to where it becomes a serious problem for example just connecting 10 dispersion compensation units would result in coupling loss between 3 to 5 db with the goal of making a dispersion compensation device or developing a dispersion compensation method that is valid for wider bandwidths but without suffering a large coupling loss fig7 through 10 are presented along with their explanation in the following discourse before going into this discussion a more detailed explanation concerning dispersion compensation is presented for a deeper understanding in fig6 b the light signal proceeds through device 420 in the following manner light enters fiber 4261 in the direction of 424 entering the dispersion compensation element 421 dispersion compensated light outputs 421 to enter fiber 426 from this point on the light experiences further dispersion compensation as it travels through dispersion compensation elements 422 and 423 the dispersion compensation experienced by the light that is output of device 420 traveling through fiber 4252 in the direction of 425 is according to the curve shown in fig5 c the structure labeled 430 in fig6 c achieves the same dispersion compensation characteristics as the device shown in fig6 a.