Surface inspection system for detecting flatness of planar sheet materials
US4255055A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 11, 1979 |
| Grant date | Mar 10, 1981 |
| Priority date | — |
| Expiry date | May 11, 1999 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B11/306
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An inspection system for detecting the flatness of planar glass sheets or other materials having reflective surfaces by observing areas of preselected size on the surfaces. The system includes a collimated beam of light directed toward the surface of the sheet material wherein the collimated beam is split into two pairs of beams superimposed one upon the other at right angles for indicating contour in two directions along perpendicularly oriented axes of the observed area. The indication of flatness is obtained by presetting the spacing between the beams of each pair of beams directed against sheet material and noting any change in the spacing occurring between the reflected beams of each pair of beams. A light beam detector, positioned in the path of each of the pair of reflected beams so as to intercept the reflected beams, detects any change in spacing occurring between the beams of each pair of reflected beams and generates a series of signals in response thereto. The signals from the light beam detectors are processed and integrated into a predetermined logic indicative of the contour of the observed area of the sheet surface for comparison to a like logic for a prescribed sur…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.