A system for processing document to scan the documents to obtain optical image data representing the document is provided. The system (10) includes elements that reduce or eliminate the effects of debris that can create streaks in the scanned images. One element is a recess (174) in the lens (170) through which an imaging device (60) scans the document. Another element is a guide (80) having an opening (84) opposing the lens (70, 170) of the imaging device (60). The opening (84) reduces or eliminates light reflecting off the guide back to the imaging device so that the area around the document is scanned as black.