Three-dimensional shape measurement apparatus
US4900144A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 25, 1988 |
| Grant date | Feb 13, 1990 |
| Priority date | — |
| Expiry date | Oct 25, 2008 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61B3/12
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A three-dimensional shape measurement apparatus uses a laser beam to illuminate an object. The light reflected from the object is processed to obtain information about the shape of the object in three dimensions. As the beam moves over contour features of the object, there is a corresponding displacement of the focal point of the light reflected back from the object which is calculated to convert it to depth-wise shape information. The apparatus includes a laser light source; deflectors for scanning the laser beam at a set frequency; an optical system for projecting the laser beam scanned by the optical deflectors at the object; detection slits arranged parallel to the direction in which the reflected light is scanned and facing the object along on an optical axis that is perpendicular to the direction of the scanning by the optical deflectors, the slits being placed a certain distance from a point that is optionally conjugate with the object; photosensors for detecting light passing through the detection slits; and a signal processor to eliminate the effect of the reflection characteristics of the object.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.