To Acquire images from various sources (such as scanners, digital cameras, and others) first select the source in the Select Source dialog box.

The data source drivers list displays the Twain compatible drivers available in the system. To select a source, simply click it.

To set the multiple images acquiring mode, check the Acquire multiple images box.
When checked, you can acquire multiple images from the same acquiring device driver dialog box.
When cleared, the device driver dialog box is closed automatically once you have acquired image.
Make sure you close the dialog box of the acquiring device driver after acquiring multiple images.