Writing device for optical memory card
US5181194A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 14, 1989 |
| Grant date | Jan 19, 1993 |
| Priority date | — |
| Expiry date | Nov 14, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B19/045
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A writing device for an optical memory card is disclosed. In this writing device, tracking correction is performed by moving a mobile objective lens of an optical system in the transverse direction of a track in accordance with a tracking error of the optical system relative to the optical memory card, and the range in which tracking correcting can be performed is enlarged by moving a retaining portion of the objective lens by a moving device when first comparison device has determined that tracking error information was outside a predetermined first standard range. The writing device includes a writing stoppage device for stopping writing data on the optical memory card when a second comparison device has determined that the tracking error information exceeded a second standard range which is wider than the first standard range. Since the retaining portion of the objective lens is moved in the direction in which any deviation occurring during tracking can be corrected, the range in which tracking correction can be performed can be enlarged. Further, since it is determined that erroneous tracking is occurring and writing of data is stopped when the deviation occurring during tracki…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.