Optical storage inspection unit calibration disk
US4988194A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Jun 23, 1988 |
| Grant date | Jan 29, 1991 |
| Priority date | — |
| Expiry date | Jun 23, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N21/9506
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A calibration disk used for an optical disk inspection unit to correct the measurement values of the mechanical characteristics, such as plane deflection and eccentricity of optical disks, and comprising at least one of three correction sections: an axial displacement correction section, a radial displacement correction section, and a focus error output voltage correction section which are formed on one or both sides of the calibration disk, concentric to the center of rotation of the disk so that measurement values, such as the surface deflection, can be corrected automatically and accurately by simply setting the calibration disk on an inspection unit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.