| 摘要 |
<p>Information-bearing discs (10) are fabricated from a first disc (20) and a second (30) disc. The first disc has a first substantially planar surface (22a) and a second surface (22b) opposite to the first surface. The second surface has first information recorded on it by means of local changes in the distance of the second surface from the first surface. The second disc is thicker than the first disc and has opposite, substantially planar, third and fourth surfaces (32a,32b). The fourth surface may have second information recorded on it by means of local changes in the distance of the fourth surface from the third surface. The second disc is secured to the first disc so that the fourth surface faces the second surface. The added thickness of the second disc eliminates rippling and buckling problems associated with bonding the discs. <IMAGE></p> |
