aEx aHx_0 OE aHu aH. aE at ax at ax a t aE at 0 oh aE ah, aH OE oox at ax o t 这里的E、H不随时间和空间变化, 可以令E=O、H=0 aez, OH, aH, c aEy at ax at OE y aH, a y=& OE ax at ax otx Hz  t Ey =e  x Hy  t Ez =e x Ez t Hy = m x Ey t Hz = m x Hx = 0  t Ex = 0 = t Hx 0 x Ex = 0 这里的Ex、Hx 不随时间和空间变化， 可以令Ex= 0、Hx= 0。 x Hz t Ey =e x Hy t e Ez = x Ez t m Hy = x Ey t Hz m =