We have suggested an ideal three-level system, which is the transition betw
een the magnetic F = 1 and F' = 1 sublevels in the Rb-87 atom, for studying
atomic coherence, and we have studied the electromagnetically induced tran
sparency(EIT) in that system. With two counter-rotating circularly polarize
d lasers, Doppler-free absorption reduction in an ideal R-type three-level
atomic system is observed up to 95 %, including optical pumping. After addi
ng an incoherent repumping beam from F = 2 to F = 1 through F' = 2, the max
imum absorption reduction is approximately the same as 95 %. In a magnetic
field, EIT shows dispersion-like spectrum because of the detuning effect of
the coupling laser due to Zeeman splitting of the magnetic sublevels.