Three-Dimensional Optical Recording on a Polyester Film Having Photochromic Thioindigo Moieties in the Main Chain

Abstract

Three-dimensional optical recording with confocal microscopy was carried out. As the recording medium, a polyester film having fluorescent photochromic thioindigo moieties in the main chain was used. Upon irradiation with focused 568 nm light from an Ar–Kr laser, the fluorescent trans forms in the film were converted into non-fluorescent cis forms. The small recorded regions were detected as dark spots by using the same laser as the reading light source. The size of the dark spots was approximately 300 nm in width and 1.5 µm in depth, which corresponds to a recording density of more than 5 Gbit/mm3.