Improved Corona-Charging-Assisted Surface-Relief Amplification on Polymer Film for Low-Noise Holograms

Abstract

The corona-charging-assisted technique for amplifying surface-relief holograms on a polymer film has been reported in recent years. However, it was found that light-scattering noise was undesirably superimposed on the reconstructed image of the amplified hologram. With a view to improving the technique for amplifying the surface relief, we explored the possible origins of the noise produced during the process. It was found that the noise originates from random submicron-scale surface structures produced during corona charging. In investigating the possibility of reducing this noise, we found that prebaking the polymer film at 150 °C for 10 min before inscribing the gratings was effective in inhibiting the generation of random surface structures. By inhibiting the generation of light-scattering noise, this prebaking process improved the optical quality of the amplified hologram. This tendency was also confirmed using a surface-relief-templated hologram recording to a glass substrate; that is, a nearly noiseless hologram was successfully transferred to the glass substrate.