Image scanner

The first image scanner developed for use with a computer was a drum scanner. It was built in 1957 at the US National Bureau of Standards by a team led by Russell A. Kirsch. The first image ever scanned on this machine was a 5 cm square photograph of Kirsch's then-three-month-old son, Walden. The black and white image had a resolution of 176 pixels on a side

In computing or computer, an image scanner is a device used to transfer images or text into a computer. There are special models for scanning photo negatives, or to scan books. In the computer, the signal from the scanner is transferred to a digital image. This image can then be edited, printed, etc. All scanners have special parts which are used to take a picture from an object. Charge-coupled device or Contact Image Sensor parts take the light from the object and change it into a digital signal. The digital signal is then transferred to the computer memory or is read in the scanner's processor. With some software it can be changed to a compressed digital image, like JPEG or PNG. Text written by hand can be changed to ASCII code by an OCR program.It is very important for computer

Types

The main types of scanner

• Desktop scanner (flatbed) This is probably the most popular type. An object to be scanned (picture, image, text sheet) is put on the glass. Under the glass, there is a moving Image Sensor.
• Hand scanner. The device is moved on the paper by hand. It was popular during the 1990s.
• Rotary scanner (Drum Scanner) used for fast scanning large numbers of sheets of paper.

Producers

• Canon
• HP
• Lexmark
• Mustek
• Plustek
• Other

Other pages

• PC camera
• Digital camera
• Digital photography

Images for kids

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  A flatbed scanner. Documents or images are placed face-down beneath the cover (shown closed here).

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  Pantelegraph
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  Caselli's pantelegraph mechanism

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  Belinograph BEP2V wirephoto machine by Edouard Bélin, 1930

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  Scanner unit with CIS. A: assembled, B: disassembled; 1: housing, 2: light conductor, 3: lenses, 4: chip with two RGB-LEDs, 5: CIS

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  DSLR camera and slide scanner

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  A hand scanner with its interface module.

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  Example of the Imaging Keyboard-Scanner

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  A photographic print being scanned into a computer at the photo desk of the Detroit News in the early 1990s.

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  Document scanner

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  Ministry of Culture, Sports and Tourism of the Republic of Korea issued a interpretation in June 2011 that it is a violation of Copyright Law to scan a book by a third party who is not a copyright holder or a book owner. Therefore, in South Korea, book owners visit 'Scan Room' to scan books by themselves.

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  sceyeX document camera.

See also

In Spanish: Escáner informático para niños