System and method for determining and controlling focal distance in a vision system camera
US8576390B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Jul 31, 2012 |
| Grant date | Nov 5, 2013 |
| Priority date | — |
| Expiry date | Jul 31, 2032 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N17/002
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
This invention provides a system and method for determining and controlling focal distance in a lens assembly of a vision system camera using an integral calibration assembly that provides the camera's image sensor with optical information that is relative to focal distance while enabling runtime images of a scene to be acquired along the image axis. The lens assembly includes a variable lens located along an optical axis that provides a variable focus setting. The calibration assembly generates a projected pattern of light that variably projects upon the camera sensor based upon the focus setting of the variable lens. That is, the appearance and/or position of the pattern varies based upon the focus setting of the variable lens. This enables a focus process to determine the current focal length of the lens assembly based upon predetermined calibration information stored in association with a vision system processor running the focus process.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.