Automated focus adjustment using a varying light pattern
AssigneeGoogle Inc.
InventorsAlexander T. Starns, Wesley Grass
Life of this patent
Estimating the term…
Abstract
Systems and methods for automatically focusing an image capture device on a page of a document object. A predetermined light pattern is projected onto the page being imaged. The light pattern varies as a function of the separation of the page being imaged from the end page. The light pattern projected onto the page being imaged is sensed. Based on the sensed light pattern, the image capture device is focused on the page being imaged.
Claims20
A document-imaging device with automatic focus capability for capturing images of pages of document objects, the device comprising:
- one or more light pattern sources that project a predetermined light pattern onto a page of a document object being imaged, wherein the pages of the document object are separated by different thicknesses from an end page of the document object and the projected light pattern varies on the page as a function of the separation of the page from the end page;
- an optical sensor that senses the light pattern projected onto the page being imaged;
- and
- an automatic focus mechanism that focuses an image capture device on the page being imaged based on a variation in the sensed light pattern.
A method for automatically focusing an image capture device on a page of a document object, the method comprising:
- projecting a predetermined light pattern onto a page of a document object being imaged, wherein the pages of the document object are separated by different thicknesses from an end page of the document object and the projected light pattern varies on the page as a function of the separation of the page from the end page;
- sensing the light pattern projected onto the page being imaged;
- and
- automatically focusing an image capture device on the page being imaged based on a variation in the sensed light pattern.
Dependencies are inferred from the claim text.