Patent ID: 7602957

Claim:
An image-based check processing system for processing financial documents, the system comprising: a document transport path along which financial documents can be transported from an upstream end to a downstream end; a focus test pattern on a background surface which is disposed along one side of the document transport path; an imaging camera disposed along an opposite side of the document transport path and facing the focus test pattern and for (i) capturing an image of a financial document along the document transport path when the financial document is between the imaging camera and the focus test pattern, and (ii) capturing an image of the focus test pattern when no financial document is between the imaging camera and the focus test pattern; an energizeable first light source of a first electromagnetic frequency and for, when energized, illuminating a financial document moving past the imaging camera to allow the imaging camera to capture an image of the illuminated financial document; an energizeable second light source of a second electromagnetic frequency which is different from the first electromagnetic frequency and for, when energized, illuminating the focus test pattern to allow the imaging camera to capture an image of the illuminated focus test pattern; and a controller for (i) controlling the first light source to energize the first light source when a financial document in the document transport path is between the imaging camera and the focus test pattern so that the imaging camera can capture an image of the financial document while the financial document is illuminated with light of the first electromagnetic frequency from the first light source, and (ii) controlling the second light source to energize the second light source when a gap is between adjacent financial documents in the document transport path so that the imaging camera can capture an image of the focus test pattern while the focus test pattern is illuminated with light of the second electromagnetic frequency from the second light source.