In terms of technologies, printers tend to be narrowed down into one of two categories: inkjet and laser. There are other smaller subcategories such as Dot Matrix and Solid Ink, too.
The way in which printers work is quite simple. In short, printers work by converting digital images and text into physical copies. They do this using a driver or specialised software that has been designed to convert the file into a language that the printer can understand. The image or text is then recreated on to the page using a series of miniscule dots. The only real difference that separates the various types of machines available is the method in which the dots are transferred onto the page.
Inkjet printers each feature a print head containing thousands of tiny holes. These tiny openings drop microscopic droplets of ink onto the paper in the printer at a speed.
Inkjet machines use a liquid ink produced either by either a coloured dye or a liquid that contains solid pigments in suspension. As the print head moves horizontally in the machine, the paper passes through perpendicular to it. As the page passes through, the individual holes in the print head are activated (usually by heat electrical current depending on the manufacturer) and a small drop of ink is pushed out onto the page. This process if performed at high speed with thousands of droplets that form together to recreate the digital text or image that is being transferred onto the media. To the naked eye, the overall image looks to be solid because the dots are so tiny.
Laser and LED machines work in a similar way to inkjet in that the image is made up of lots of tiny dots, which, when viewed as a whole, appear to be a solid image. However, the method in which is adopted in creating those tiny dots is vastly different. So, where an inkjet uses liquid dots, a laser machine uses dots made up of toner – a fine powder of solid particles.
When compared with an inkjet machine, lasers are much more complex. These machines rely on many more stages during the process than inkjet. In simple terms, the basic process uses a light source (laser/LED), drum (mono) or multiple drums (colour) and toner.
In order to create an image on the page, the drum is first charged and then the laser or LED is shone onto the drum in the outline of the intended image. The toner itself is attracted to areas of the drum that have the charge knocked off and a series of rollers transfer the powder from the toner cartridge and presents it at the drum. The areas that are charged repel the toner and the area that is not attracts the toner particles which are pulled onto the drum and stick to the parts that make up the image. At the same time, the paper is also transported to meet the drum, which, in turn, transfers the image across to the page itself.
The paper is then passed through a fuser unit (hot roller) which applies heat and pressure to melt the toner particles so that they stick to the page and create a finished image.
Available only from Xerox, solid ink printers perform in a way that combines the printing methods of both inkjet and laser printers. Solid wax is melted and sprayed onto a large drum unit using a print head similar to that found on an inkjet printer. The image is created onto a large metallic roller that then transfers directly to the page. Once dry, you are left with an image made of a crayon-like substance. Solid ink printers are renowned for producing vibrant, colourful prints that really stand out.
And there you have it – a full simplified breakdown of how printers work. We hope that you’ve found it useful!