OE aH. aE Ox at ax at aE aH. H y=& OE Ox at ax at aE aH OH ax ot ax ot ax OH. OE 8y 0E, ax at ax at at E 消去H得到: y-8u Ox atx Hz t Ey =e x Hy t e Ez = x Ez t m Hy = x Ey t Hz m = x Ey t Hz m = x Hz t Ey =e x Ey 2 2  Ey 2 2 t =e m t m  Hz = x Ey 2 2 2 x x Hz t = 2  Ey 2 2 t e 消去Hz得到：