  We report on optical studies of the thin films of multiferroic hexagonal
(P.G. 6mm) rare-earth orthoferrites RFeO3 (R=Ho, Er, Lu) grown epitaxially on a
(111)-surface of ZrO2(Y2O3) substrate. The optical absorption study in the
range of 0.6-5.6 eV shows that the films are transparent below 1.9 eV; above
this energy four broad intense absorption bands are distinguished. The
absorption spectra are analyzed taking into account the unusual fivefold
coordination of the Fe(3+) ion. Temperature dependence of the optical
absorption at 4.9 eV shows anomaly at 124 K, which we attribute to magnetic
ordering of iron sublattices.
