Topography measuring apparatus
US4902123A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 25, 1987 |
| Grant date | Feb 20, 1990 |
| Priority date | — |
| Expiry date | Nov 25, 2007 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61B3/152
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A contour measuring apparatus and method of using the apparatus is disclosed to measure the three-dimensional contour of a surface. A multi-point light source directs a plurality of light beams onto the surface to be measured. The light beams are reflected through a lens onto a photodetector to produce electro-optically measurable optical images. A structure is provided to determine the local radius of curvature of the surface at each desired point of incidence of individual light beams and the three-dimensional surface contour of the surface being measured. A calibration device is provided to reduce instrument errors of the apparatus. The calibration device includes a calibration surface with a known contour to be positioned in substitution of the surface being measured. The apparatus includes a structure to sequentially determine and store a memory of the location of the calibration surface and to compare the reflection of the light from the calibration surface as well as the surface being measured to determine the contour of the surface being measured.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.