OPTICAL DISC WRITE/READ EMPLOYING PASSIVE FOCUS MAINTENANCE

摘要

OPTICAL DISC WRITE/READ EMPLOYING PASSIVE FOCUS MAINTENANCE The quality of spot-focus of optical writing and reading light upon the information surface of a flexible optical disc is passively enhanced by (1) rotating the disc with its neutral plane stabilized in space and (2) directing such light through the optical disc support into precise spot-focus on the information surface. With this technique spherical aberration induced by the disc support compensates for thickness variation of the support. Various structural embodiments are disclosed.