Intro to Scanners

A scanner works by creating a digital image. When you scan a document, you are making a picture of it. This digital image can be used in documents, websites, or printed individually.

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A scanner’s mechanism consists of a light source and a row of light sensors. As light is reflected from individual points on the page, it is received by the light sensors and translated to digital signals that corresponds to that point.

The resolution of scanners is similar to that of printers, approximately 300-600 dpi (dots per inch). Most modern scanners can produce black and white or color scans of anything placed on the glass plate.

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Some scanners even convert the picture they take into text. These scanners use a software known as OCR, Optical Character Recognition. It is not always perfect, so some misspelling happens, but the result is placed into a word document and is easy to correct.

Another type of scanner is the sheet scanner. Multiple pages can be fed into this scanner, one right after the other. It often looks like a printer.

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The last type of scanner is a hand held version. This is most often used to scan barcodes.

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