Optical Disk System Using a High-Numerical Aperture Single Objective Lens and a Blue LD

An optical disk system using a blue laser diode and a single objective lens that has a numerical aperture of 0.7, is proposed. A sufficiently low jitter value was obtained with a read-only disk having 17-Gbyte capacity. The paper also includes discussion on the influence of the laser noise and RF modulation method on the playback signal.