Focusing system for a telecentric optical measuring machine
US10126540B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 21, 2016 |
| Grant date | Nov 13, 2018 |
| Priority date | — |
| Expiry date | May 16, 2037 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N25/61
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method of focusing a telecentric imaging system (30), particularly as a part of a measuring machine (10) includes measuring an image of a feature (25) of an object (24) through the telecentric imaging system (30) in a telecentric operating mode and measuring an image of the feature (25) of the object (24) through the telecentric imaging system (30) in a non-telecentric operating mode. A value is acquired characterizing a function by which the size of the imaged feature varies in the non-telecentric mode with the relative displacement of the object (24) through the depth of field (D). The measures of the image of the feature (25) of the object (24) in the telecentric and non-telecentric modes are related to each other and to the acquired value as an estimate of a relative displacement of the object (24) from the best focus position.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.