Optical disc with magnetic member in a recessed portion thereof and method for producing said optical disc

An optical disc, comprising:

• a disk-shaped substrate of unitary construction and having a first surface with a first opening therethrough, and a second surface substantially parallel to said first surface, said first surface being formed with a recess portion around the first opening and having a recording layer, said first opening having a first diameter and said recess portion having a second diameter larger than the first diameter, said second surface being formed with a first projection which is unitary with said second surface, said first projection having a second opening therethrough connected to said first opening, wherein a top surface of said first projection is parallel to said second surface and is dimensioned to be received by a means for rotationally driving the optical disc;
• and
• a plate-shaped magnetic member arranged in said recess portion,
• wherein a second projection is formed on said first surface around said recess portion and supports said magnetic member, said second projection is of unitary construction with the first surface, said second projection has a first portion and second portion of unitary construction with the first portion, said first portion is formed to project from said first surface, and said second portion is formed with the first portion, at a free end of said first portion and to hang over said recess portion and said magnetic member, so that said second portion retains the magnetic member in said recess portion.