Wide write disc certification process, apparatus and article of manufacture
US6104556A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 18, 1997 |
| Grant date | Aug 15, 2000 |
| Priority date | — |
| Expiry date | Nov 18, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B33/10
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A disc certification process, apparatus and article of manufacture for improved testing efficiency employs a testing head having a write element and a read element supported adjacent a rotating disc recording surface. The write element has a width that defines a "wide" write track width of at least N times the read track width defined by the width of the read element, wherein N is an integer greater than 1. The write element writes a signal onto the recording surface of the disc during a first disc rotation, to define a first annular write track having a "wide" first write track width in the radial direction of the disc. Then, during a second rotation, the read element reads the signal written in a first reading track width defined within the "wide" first write track. Thereafter, the read element is stepped to another read position adjacent the first write track and the read element reads the signal written onto the recording surface in a second reading track width defined within the first write track. If the write track width is more than two times the width of each read track, then the read element may be stepped to one or more additional read positions to read the signal written…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.