Systems for inspecting defects in an optical recording medium
US5067812A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 23, 1990 |
| Grant date | Nov 26, 1991 |
| Priority date | — |
| Expiry date | Jan 23, 2010 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N21/95623
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The present invention provides a defect inspecting apparatus which can easily and accurately carry out the inspection of a defect in a recording medium and which does not require electrical image processing or image processing by means of software in order to eliminate a regular pattern. This defect inspecting apparatus has an optical image forming system, such as a microscope, which enlarges an optical recording area of an optical recording medium having a regular pattern and an image processing part which converts the enlarged image sent from the optical image forming system into an image signal and detects the defect in the optical recording area from the image signal. In addition, a space filter which eliminates the space frequency component of the regular pattern is mounted on the optical image forming system.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.