A diamond-like carbon(DLC) films were deposited on the borosilicate glass substrate by radio frequency plasma enhanced chemical deposition(rf-PECVD). The $methane(CH_4)-hydrogen(H_2)$ gas mixture was used as precursor gas. The morphologies, the structure and the optical properties of the DLC films were investigated by SEM, Raman and UV spectrometer. The deposition rate was slightly increased with the hydrogen concentration in the gas mixture and it maintained constant at over 25 sccm of the gas flow rate. The optical band gap calculated by UV spectra decreased with increase of deposition time and DC self bias, but that were not effected by hydrogen content. Most effective parameter on the transmittance of film was bias voltage, especially in the range of ultra violet and visible light.