Patent ID: 6965550

Claim:
An optical disc discriminating apparatus for discriminating plural sorts of optical discs in which data are recorded in a groove presenting a wobble, or a land, of an optical disc, said groove presenting the wobble indicating addresses, and in which the optical discs are of the same outer shape but differ in the recording capacity, said apparatus comprising: rotational driving means for rotationally driving said optical disc; optical means for converging the light for reading out data recorded in said wobble of said optical disc on said optical disc by a converging lens; tracking error detecting means for detecting a tracking error signal for said groove, presenting the wobble, from the light focused on said optical disc by said optical means and reflected back from said groove presenting the wobble; total light volume signal detection means for detecting a total light volume signal of a mark recorded on said groove, presenting the wobble, from the reflected light from said groove, presenting the wobble, on which the light has been focused by said optical means; and discriminating means for discriminating the sorts of said optical discs based on phase comparison between a binary-coded version of said tracking error signal detected by said tracking error detection means and a binary-coded version of said total light volume signal as detected by said total light volume signal detection means.