The program receives image data from the scanner and performs a process called optical character recognition. OCR recognizes individual letters in the image and builds text from them automatically.
Once the computer has this information, you can edit, search and save it as if it were a word processing document. This is what distinguishes document scanning from simple image scanning -- the ability to extract text from document images. Chicago native John Papiewski has a physics degree and has been writing since He has contributed to "Foresight Update," a nanotechnology newsletter from the Foresight Institute.
What Are Handheld Scanners Used for? How Does a Flatbed Scanner Work? Share on Facebook. Description Document scanners come in different types. While a normal printer will apply ink to a medium in order to represent the scanned image, photocopiers use a method of dry electrostatic printing. Instead of ink, copy machines, including laser printers, use a dry, powdered material known as toner to create images.
Scanning photos requires much more sensitive technology than scanning regular documents. While there are all-purpose scanners that exist for photos and regular text documents, usually photo scanning is best left to a dedicated photo scanner.
Sometimes, photos scanned through a dedicated photo scanner can be cleaned up and color corrected before the file is even on your computer screen. While a flatbed scanner may be the most well-known, there are many other types of scanners suited to specific purposes.
In addition to the flatbed scanner, you can also find portable scanners and sheetfed scanners. The flatbed scanner is usually immobile and takes up a lot of space, but their low price makes them attractive to the average consumer. Since a scanner often works on a printer in tandem, many varieties of printers come with an attached scanning bed. If you need a scanner for basic copying or uploading functions, those that are equipped with a printer are the most cost-effective.
Portable scanners are exactly what they sound like: scanners you can easily transport in a suitcase or computer bag. Their scanning power is greatly diminished, however, as their size requirements permit only the most basic and necessary functions. Beyond their portability, many of these scanners are also captivating due to their additional features.
Some allow you to scan directly to your computer through a USB connection, while others have memory card slots that let you scan without your laptop.
Some newer models even offer Wi-Fi connectivity to store or preview scans on your phone or tablet. If your business necessitates a lot of travel and you need to have constant access to a scanner, this is an ideal model to consider. Sheetfed scanners are smaller than flatbeds, but not considered portable. Their popularity is due to the speed in which they can scan documents, as instead of placing one sheet on the surface at a time, this scanner allows for multiple pages to be simultaneously queued up.
In most scanners, the sensing medium is an electronic, light-sensing integrated circuit known as a charged coupled device CCD. Light-sensitive photosites arrayed along the CCD convert levels of brightness into electronic signals that are then processed into a digital image.
CCD is by far the most common light-sensing technology used in modern scanners.
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