High speed scanning method and apparatus
US4498778A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 29, 1982 |
| Grant date | Feb 12, 1985 |
| Priority date | — |
| Expiry date | Sep 29, 2002 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B11/25
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method and apparatus for determining the spatial coordinates of a workpiece including: a precisely formed jig; a planar light source; an electronic imaging device adapted to view the intersection of the planar light with the jig and the workpiece; a video digitizer for sampling and digitizing output signals from the imaging device and in particular reference pulse signals representative of said intersections; digital logic circuitry for algebraically summing video samples to determine the centroid or geometric mean of the reference pulses; and a computer for calculating calibration parameters based on knowledge of the form of the jig and scans of the jig, and applying those calibration parameters to scans of the workpiece to calculate spatial coordinates of the workpiece. A method of determining the centroid of a sensed pulse signal including the steps of integrating the signal over a selected interval including the pulse by analog or digital means, integrating the result of the first integration in like manner and dividing result of the second integration by the result of the first integration.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.