Surface configuration inspection apparatus with moving grating
US4742237A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 13, 1987 |
| Grant date | May 3, 1988 |
| Priority date | — |
| Expiry date | Apr 13, 2007 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B11/2527
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A surface configuration inspection apparatus comprising a movable member having a grating with parallel equidistant dark and light lines on a transparent plate, and a driving device for causing the vertical movement of the movable member. A projection device projects an image of the grating onto a screen disposed by the object to be inspected. A detector detects the image of the grating on the screen by reflection from a reflective surface on the object to be inspected and displays a deformed pattern of the grating. The deformed pattern changes with the movement of the grating. According to the deformation and the change of the deformation, defects such as projections, depressions, scratches or the like can be identified as to their size and shape.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.