How Scanners Work

Scanners come in several different types. The one most commonly used is a flatbed scanner because it is most versatile and most common. Most scanners have a single pass method and split the image into three smaller versions. Each smaller version passes through a color filter (either RGB) and onto a discrete section of the CCD array. There are two kinds of array technology, CIS and CCD. The CCD array gives a better quality image. The CIS array is less expensive but does not provide the same quality.

Scanners vary in resolution and sharpness. Interpolation is a process that scanning software uses to increase the resolution of an image by creating extra pixels between the ones actually scanned.

The USB image transfer is a combination of good speed and ease of use. A computer needs a software called a driver to communicate with the scanner. A common language is TWAIN (Technology Without An Interesting Name), which most scanners understand. The TWAIN driver acts as interpreter between an application that supports the TWAIN standard. An example would be PhotoShop.