The total electric field is given by
..................................(6.76)
Similarly, total magnetic field is given by
.............................(6.77)
From eqns (6.76) and (6.77) we observe that
- Along z direction i.e. normal to the boundary
y component of
and x component of 
maintain standing wave patterns according to 
and 
where 
. No average power propagates along z as y component of and x component of are out of phase.