Write test method for use in recording process for recording information by modulating the power of a laser light thereby forming a high-temperature state and a low-temperature state on a recording medium
US5815477A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 30, 1996 |
| Grant date | Sep 29, 1998 |
| Priority date | — |
| Expiry date | Jan 30, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B11/1053
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A write test method for use in a recording process for recording information is effected by such that the power of a laser light is modulated to form a high-temperature state and a low-temperature state on a recording medium. First, a predetermined signal is recorded on the recording medium while varying the power level of the laser light. The information recorded on the recording medium is reproduced to detect the power level of the laser light, immediately before formation of the high-temperature state, based on the amplitude of a reproduced signal. The power levels of the laser light for forming the low-temperature state and for forming the high-temperature state are determined on the basis of the detected power level.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.