  We report the absorption/transmission properties of thin copper films
slightly below the percolation limit produced by laser ablation; these samples
show randomly positioned islands. Two types of films are grown: in the first
type, copper is deposited on glass, and it is shown that as the amount of
deposited copper approaches the percolation limit, the samples show enhanced
light transmission; in the second set of samples, made of TiO$_2$/Cu/TiO$_2$
layers, the presence of titanium oxide inhibits light transmission enhancement,
even though the same amount of copper has been deposited compared to the
samples deposited on glass. We also present numerical calculations based on the
discrete dipole method to simulate the optical behaviour of the copper films.
The enhanced light transmission of the samples presented in this work resembles
the Extraordinary Optical Transmission (EOT) observed in periodic metallic
structures. The similarities and differences between experiment and numerical
calculations and the possible use of these films as sensors are discussed.
