Just like computers have become a staple commodity, the many devices that enable them function are also following their way. Scanners today are like basics for the computer. Be it for office use or for home use, a scanner is a must have device. And they truly have all the reason to be on the list. Let us begin with understanding the scanner and then the types of it. A scanner can be termed as a device that enables the conversion of a picture or a graphic on a surface, into a digital code that can be understood by the computer memory, for it to display it on the screen.
The reason for using scanners or devices that can convert the picture in digital code is that, the computer does not read or understand the graphics in their original format. These have to be converted in a code that will be understood by the computer. The scanner converts the information to a digital code for the computer. The mechanism or technology that enables the scanner to do so is a software called Optical Character Recognition (OCR). There are different types of scanners available in the market. We are going to discuss flatbed scanners, and more on its working.
How do Flatbed Scanners Function
There are many flatbed scanners that you will find, but choosing the right one is important. Some of the best options will give you quicker and more efficient results. A flatbed scanner will typically have a glass window, that is the surface where the object to be scanned is placed. The graphic or object will be placed on top of the glass. All you will have to do is place the document carefully on the glass, the document should be placed with the section to be scanned facing down. Now close the cover of the scanner and press the button for scan. Now let us see what exactly takes place inside and how does the scanner operate.
- Along with the glass bed, the scanner has a source of light, which is in-built. Most commonly the light used is LED or fluorescent. This light is regulated by a voltage regulator or a similar device. This enables the light to spread evenly across the document.
- This light source then illuminates the document, this is when the actual encoding of the document takes place. The scanner contains a lens, mirror a filter and a CCD array, that are fixed on the top, called the scan head. This combined mechanism then rolls or moves over the entire document. The scan head takes help of a belt.
- The scan head is fixed to a bar that acts like a stabilizer. So the entire process takes place smoothly, without any wobble or deviation.
- An angled mirror then reflects the image of the document, on another mirror. After the image is reflected on this second mirror, it gets reflected again on the lens.
- This lens then projects the captured image on to the CCD array, through a filter.
This is how the encoding takes place and once in the CCD array, it gets decoded by the computer, which is when the document is reflected on the screen, exactly the way it is. Scanners have made digital life easy and have also helped in storing important papers and documents digitally. The working principle is pretty simple, and if you must have noticed, it takes only a few seconds to scan any sheet or document. So the next time you scan a document on a flatbed scanner, you know what's processing under the beam of light!