Image scanner, which is commonly referred to as “Computer scanner” or just “Scanner”, is an electronic device which scans images, text, etc and converts them into digital content. The digital content can be stored in various storage devices like hard disk, flash drive, etc. The first scanner was manufactured in 1957. Scanners generally use CCD (Charged Coupled Device) or CIS (Contact Image Sensor) as image sensors. There are various scanners available in the market – manufactured by reputed companies like HP, Epson, etc – with price range varying from $100 to $1500.
Types of scanners:
Flatbed scanners: These are the regular scanners which have become very popular in offices all over the world. They come with a flip – up cover to protect the glass plate on which the document to be scanned should be placed. This plate is illuminated using the light beneath it. The sensor and the light move across the document, there by scanning it and producing a digital image. Using flatbed scanners, you can occasionally scan books and DVD covers. But the disadvantage is that you can scan only one document at a time.
Sheetfed scanners: These are smaller when compared with flatbed scanners. To scan images you need to feed sheets in to the scanner through the slot which would be provided. Resolution is less when compared to flatbed scanners. This is ideal if you intend to use your scanner to scan only documents and if your usage is more. This scanner enables you to feed sheets in bunches.
Photo scanners: Photo scanners are ideal if you intend to scan high resolution images. You can also scan slides and images using these scanners. Companies are providing useful software programs along with photo scanners. Some models come with in built software which helps in cleaning old photographs. These are slightly more expensive than regular flatbed scanners.
Portable scanners: As the name indicates these scanners are easy to carry around. Some of these scanners even fit into your pocket. There is an application by name “Pocket Scanner” for the iPhone, which enables you to scan documents and to convert them into PDF files. These are ideal if you are into espionage.
Before purchasing a scanner it is important to spend some time in analysis of your requirements. Then you are more likely to make the right decision.