Automatic focusing of every image point in an image
US4350884A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 19, 1980 |
| Grant date | Sep 21, 1982 |
| Priority date | — |
| Expiry date | Mar 19, 2000 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B7/36
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Every image point of an image of a sample formed by an optical objective, focussed by, for each image point, deriving a representation of the autocorrelation function of the brightness distribution of the image of that image point, deriving a representation of the average of the autocorrelation function of the brightness distribution of a plurality of image points in the region of that image point, deriving a representation constituting a function of the quotient formed by dividing the representation of the autocorrelation function for that image point by the representation of the average of the autocorrelation function, and varying the distance between the objective and the sample while iteratively performing the above steps of deriving for determining the distance at which the function of the quotient has a maximum value.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.