Publisher : The Korean Society of Mechanical Engineers
DOI : 10.22634/KSME-A.19184.108.40.2060
Title & Authors
On the Birefringence Distribution in Optical Disk Substrate Fabricated by Injection Compression Molding Kim, Jong-Seong; Kim, Hyeon; Gang, Sin-Il;
It is necessary to improve mechanical and optical properties in the optical disk substrates as the information storage devices with high storage density using short wavelength laser are being developed. Injection compression molding is regarded as the most suitable process to manufacture optical disk substrates with high dimensional accuracy, low residual stresses, and superb optical properties. In the present study, polycarbonate optical disk substrates were fabricated by injection compression molding and the birefringence, regarded as one of the most important optical properties for optical disk, is measured. The effects of various processing conditions upon the development of birefringence distribution were examined experimentally. It was found that the values of the birefringence distribution were very sensitive to the mold wall temperature history and the variance of the birefringence distribution in the radial direction was affected by the level of the packing and the compression pressure.
Optical Disk Substrates;Birefringence;Injection Compression Molding;Optical Information Storage Device;
Analysis of Residual Stresses and Post-Molding Deformation in Injection-Molded Components, 1992.