Method to detect a type of disc

摘要

A method detects a disc using signals generated from a light irregularly reflected from pits formed on a recording surface of the disc. The method detects a ratio of a peak-to-peak value of a first signal generated from the irregular reflection to a peak-to-peak value of a second signal generated from the irregular reflection. The method further detects the disc according to magnitudes of the first and second signals and the detected ratio.