How does a scanner ?

How does a scanner ?

Scanner - a very useful invention of the twentieth century.During the huge circulation of various documents scanner is widely used in offices and at home.Generally referred to as a scanner device that allows you to transfer the information or images on the surface of, in digital format.The conversion process is called scanning information.This process is quite complicated.Probably, many became interested in how the scanner works.Let's try to understand this intricate mechanism in this article.

Technical principles of scanner

scanner optics consists of mirrors and lens.The light source sends light rays to the original that you want to get on a computer screen.After that, the light reflected, gets on the very same optics.This results in an electric signal which contains information about the activity at the point of color of the scanned image.Further, the color signal through a hardware interface to the computer on which the information is decrypted by a special program that works with the scanner.

information is completely displayed on the computer screen.To better understand how the scanner, you need to understand the mechanism of this device.The most important detail of the device can be called a reading head that moves up and down image.This head is a photodetector.Two types fotoprinimayuschey matrix.

  • One of them - the PDS matrix (Charge Coupled Device), which consists of a plurality of sensors that convert the light falling on them
  • Other - CDI-matrix (Contact Image Sensor).The CDI-scanners use LEDs, and to scan a color image is required to have three LEDs per pixel.

As the scanner passes

information now faced with scanning everything.For example, a supermarket cashier scan the bar code printed on the pack of the goods, and the screen displays the name of the price and the amount of the purchase.And yet I wonder how a barcode scanner, how he manages to convey such information to the screen.

barcode scanners are light-emitting diode, laser and image scanners.The LED devices emitting element is an LED.Read information from the CCD.laser devices are also used, which are more comfortable.

Imager - the peak of fashion.They are the most reliable, fast, high-quality and impact resistant.Also, they are able to assume any barcode.The information is put a bar code on the product, and at the direction of the light beam, it is read and converted on a computer screen or other device.The principle of operation of such scanners is the same as the conventional one.However, the complexity lies in the fact that is scanned is not the information itself, which is located on the original, and the encrypted information in special codes.