Printers Vs Scanners

Printer is an output device that prints text or image on to a physical medium like paper whereas scanner is an input device that scans object so that the image will be displayed and used by the computer. In printing, data is moved from computer to printer. But, in scanning data is transferred from scanner to computer in digital form.

A printer is a peripheral device which is tagged on to a computer locally by means of printer cable or USB cable.But, there are also network printers having its own built-in network interface and thus serving for any computer in the network.Some printers include many functions other than printing like copying, scanning etc. and are called as multifunction printers or all-in-one printers. After giving print command, printing process takes place and at one full swoop, you can do some other work with your computer, as the jobs will be placed in a buffer and executed in order. This simultaneous processing of functions is named as spooling.

Printers are generally classified into two types namely impact and non-impact printers. In impact printers, there will be a contact between the paper and the printing mechanism. Dot-matrix printers, character printers, line printers, Daisy-wheel printers, thermal printers etc. come under this category. In dot-matrix, there will be series of pins which strike on the inked ribbon to produce image on the paper. In character printer, there will be series of bars having the characters on them, which then strike on the inked ribbon to generate characters on the paper. Daisy wheel printer makes use of a metal or plastic wheel and it can print characters alone. Calculators, fax machines include thermal printers. Line printers are always sooner. These impact printers are toppled by the spanking non-impact printers, wherein there won't be any direct contact between the paper and the mechanism. Inkjet and laser printers of this type revolutionized color printing. In inkjet, the head will have tiny nozzles which spurt out ink droplets to produce image on the paper.

Scanners are hardware appliances which analyze the text or image, then capture and process them so that the data converted into digital form will be procured and displayed by the computer. Scanner can convert different levels of analog voltage into digital form. Scanners incorporate optical character recognition software that captures text or image. CCD array, an array of tiny light sensitive diodes, is the focal component of scanner. These diodes or photosites amend photons into electrical charges. Each photosite is light-sensitive and turn out charges accordingly. Various filters, lenses are present in scanners. Scanner can be attached to a printer and you can make copies of the object you scanned. If it is attached to your pc via USB cable, you can have scanned images on your pc. Flatbed scanner is the simple and rife one. In sheet-fed scanner, the object to be scanned is moved, since the scan head is hard and fast. Handheld scanners need the user to move them to capture images. Drum scanners use photomultiplier tube technology to ensnare astonishingly large images and are used in publishing industries.

Mono-chrome printers produce images in one color and by and large it is black. Color printer produces colored images. Scanners normally open the door to RGB data from the array. The data will be processed and sent to computer. Banking on the scanning array characteristics, the color depth varies. The resolution is measured in pixels per inch.

Printers are omnipresent these days. They are used in offices, schools, colleges, hospitals, companies, shops etc. They are outstripped so much that it can be directly attached to digital cameras etc. 3D Scanners are used in industrial design, gaming, test and measurement, orthodontics etc. Planetary scanners are used to scan books, large documents etc. Scanners are also used in photography, bio-medical research etc.