What happens in scanning

1.	What happens in scanning
Answer» <p>Where the device is moved by hand, have evolved from text scanning "wands" to3D scannersused for industrial design, reverse engineering, test and measurement,orthotics, gaming and other applications. Mechanically driven scanners that move the document are typically used for large-format documents, where a flatbed design would be impractical.</p><p>Modern scanners typically use acharge-coupled device(CCD) or acontact image sensor(CIS) as the image sensor, whereasdrum scanners, developed earlier and still used for the highest possible image quality, use aphotomultipliertube (PMT) as the image sensor. Arotary scanner,used for high-speed document scanning, is a type of drum scanner that uses a CCD array instead of a photomultiplier. Non-contactplanetary scannersessentially photograph delicate books and documents. All these scanners produce two-dimensional images of subjects that are usually flat, but sometimes solid; 3D scanners produce information on the three-dimensional structure of solid objects.</p>

Discussion