What is Scanner in Computer?- Types of the scanner
The scanner is a device used to convert paper documents into electronic files.
The printer and scanner are totally different from each other. The printer prints the in hardcopy while the scanner converts the printed text into softcopy. So there are many differences between printers and scanners according to their functionality.
When was the first scanner created?
The first scanners were invented in the 1860s, but the scanner we know today was created in 1957 by Russell Kirsch at the United States National Bureau of Standards. The first image scanned by this device was a black-and-white picture of Kirsch’s son, which measured only 5×5 cm and had a resolution of 176 x 176 pixels.
Types of scanner
There are two types of the Scanner
- Optical Scanner
- Optical Reader
An optical scanner is a device that uses light reflected off an object to create an image of the object. An optical scanner works by projecting a beam of light onto an object and then detecting the amount of light reflected back at different angles.
The scanner then converts these measurements into digital data that can be stored and manipulated using the software. There are many types of scanners including flatbed scanners, drum scanners, sheetfed scanners, and handheld scanners.
Data can be communicated in many ways. It can be displayed on a screen or printed out on paper. Additionally, it can be sent electronically via email or posted on a website. Finally, data can also be stored permanently for later use.
The standard resolution for scanners is 300 or 600 dpi. This resolution however does not guarantee a high-quality scan. In fact, it is quite the opposite. A high-resolution scan provides a sharper and brighter image and a smaller file size. Most professional scanners offer 1200 dpi or more.
An optical reader is a device that uses a light source to read characters, marks, and codes
Types of Optical Scanners
Different types of optical scanners are as follows:
Flatbed scanners are the most popular type of scanner. These scanners have a glass plate where the image is placed. The user then slides the document under the glass plate and presses it down on the document.
As the document passes over the glass plate, the scanner captures the image. Flatbed scanners are often used for copying documents and making copies of artwork.
Sheetfed scanners use a roll of paper instead of a glass plate. The user places the document on top of the roll of paper and rolls the paper back and forth across the scanner. The scanner reads the image as the paper moves past the sensor. Sheetfed scanners are often used for scanning business cards, receipts, and invoices.
A handheld scanner is a portable, digital input device. To use it, you must move it by hand over the document or surface you wish to scan. The images or text are then transferred onto your computer or another electronic device.
Handheld scanners are most often used for scanning short articles, single lines of data, or small amounts of text like web addresses, names, and phone numbers. Some models even come with trays to help you keep the scanner moving in a straight line.
A drum scanner is similar to a flatbed scanner except that instead of a glass platen, it has a rotating drum coated with a reflective material. The document is placed inside the drum and moved past the scanning head. As the drum rotates, the scanning head reads the information from the document.