7. Other Functions
Double Feed Detection Function
The scanner is equipped with a [Double Feed Detection] function that automatically detects when two or more documents are fed at the same time (double feed) while doing continuous scanning.
There are two methods for multiple feed detection as shown below, the detection method is selected by the “ISIS/TWAIN driver”.
Detecting Double Feed by Document Length
This detection method is effective when scanning a document on pages that are all the same size. The length of the first page scanned is used as a standard against which the rest of the pages are compared. If any page is 1.96" (50 mm) longer or shorter than the first page it is considered a double feed and scanning stops.
Detecting Double Feed with Ultrasonic Waves
This detection method is effective when scanning a document on pages that are different sizes. Ultrasonic waves are used to detect pages that are fed at the same time as well as the space between pages. Scanning stops if they are detected.
Note
•Ultrasonic double feed detection works when the documents overlap by 1.96" (50 mm) or more.
•If the documents are stuck together with static electricity, the ultrasonic double feed detection will not correctly detect them as a double feed.
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