  We study the effect of the energy gap on the transmission of fermions in
graphene exposed to linearly polarized light as a laser barrier. We determine
the energy spectrum, apply boundary conditions at interfaces, and use the
transfer matrix approach to obtain transmissions for all energy modes. We show
that when the energy gap increases, the oscillations of transmissions decrease
dramatically until they vanish entirely. However, when the barrier width
varies, the oscillations become more significant and exhibit sharp peaks. By
increasing the incident energy, the laser field suppresses the Fabry-P\'erot
resonance, and the transmissions move to the right when the energy gap is
tuned.
