SCANNER DOCUMENT ABSENCE CODE SYSTEM
Original Publication Date: 1991-Oct-31
Included in the Prior Art Database: 2004-Apr-05
Xerox Disclosure Journal
A scanner document absence code system used in an electronic imaging system to detect documents left on a platen glass is disclosed. When manual handling of a document to be imaged is desired, the document is manually positioned in a special registration position on the platen glass. Over one corner of the manual registration position is a signal generating optical indicia. This optical indicia is a numbered bar code pattern on a stationary baffle, or other overlying surface, upstream of a document feeder transport, and preferably located at a start-of-scan area. An electronic imager maybe partially or entirely optically blocked from reading the bar code pattern by a document present in that manual registration position. Using a bar code reduces the probability of error in false detection when a document is not present.