Method of manufacturing an optically readable disc record and disc record manufactured in accordance with the method

A method of manufacturing an optically readable disc record comprising two discs which are injection molded from a plastics material and which are concentrically affixed to each other by welding, which method comprises:

• (a) manufacturing a thin disc-shaped matrix,
• (b) making local recesses in the matrix,
• (c) injection-molding discs from said matrix, said discs having projections corresponding to said recesses,
• (d) arranging two of said discs on each other in a manner such that projection-free areas in one disc contact projections in an opposing disc,
• (e) and applying energy to at least partly melt said projections to weld the discs to each other, characterized in that for forming said recesses use is made of an indenter pin having a sharp end which is impressed into a surface of said matrix, thereby locally forming a pit-shaped recess surrounded by a ridge of displaced material whose volume is substantially equal to the volume of the pit-shaped recess, and that during injection-moulding each disc is formed with corresponding pin-shaped projections each surrounded by a groove whose volume is substantially equal to the volume of that portion of the projection which protrudes from the disc surface.