  We derive the low-energy Hamiltonian for a honeycomb lattice with anisotropy
in the hopping parameters. Taking the reported Dirac Hamiltonian for the
anisotropic honeycomb lattice, we obtain its optical conductivity tensor and
its transmittance for normal incidence of linearly polarized light. Also, we
characterize its dichroic character due to the anisotropic optical absorption.
As an application of our general findings, which reproduce the case of
uniformly strained graphene, we study the optical properties of graphene under
a nonmechanical distortion.
