Change in data marks and groove structures of compact recordable disks in response to a high power laser beam

Abstract

Changes in data marks and groove structures are examined when a high power laser beam (>0.5 W) is focused on compact disk recordable (CD-R) data layers. Observations are recorded as a function of exposure condition and the type of dye used in the recording layer. All samples experience a decrease in the depths of data mark features and the pregroove modulations on exposure. Data marks on cyanine- and azo-dye disks become optically invisible after exposure, while data marks on phthalocyanine-dye disks remain visible, even after high-power exposure. Also, phthalocyanine-dye disks show interesting phenomena, including mixture of the dye and the substrate material during recording and contrast reversal of the marks.