Dot matrix printers are the oldest in use today. They display the image on paper in the form of individual dots in a striking manner. This technology is outdated today, but is still used in cases where inexpensive mass printing in large volumes is required with low requirements for the quality of the resulting document.
Dot matrix printers appeared in 1964. Their movement was developed by engineers at Seiko Epson Corporation. In this type of computer printers for forming an image, there is a print head, which consists of a set of needles. This head is fixed on a carriage, the movement of which is set by the guides located across the sheet of the carrier. The needles that make up the head are driven by electromagnets. In a given sequence, the needles strike the paper through the ink ribbon. These ribbons are used in conventional typewriters and are supplied in cartridges. Thus, a bitmap is formed. The print speed of printers using this technology is measured in characters per second, or CPS. Dot matrix printers allow you to print on media of different thicknesses, for which they are equipped with a mechanism for adjusting the gap between the paper roll and the print head. The print resolution of a dot matrix printer, like the print speed, depends on the number of needles in the print head. The most common printers have 9 and 24-pin heads. 9-pin printers offer high-speed printing at low quality levels. Whereas 24-pin printers offer high print quality, but much slower speed. The print media for dot matrix printers is mainly roll or perforated fanfold paper. When using sheet paper, most models require manual threading. Some models are equipped with a cut-sheet automatic document feeder mechanism. Multi-color printing is also possible using dot matrix printers. Some models offer the option of using four-color CMYK ribbon. To change the color in such printers, a mechanism is provided that displaces the cartridge with the ribbon loaded in it relative to the print head. On a color dot matrix printer, you can get 7 colors. In this case, 4 primary colors are printed in one pass, and additional colors - in two. Multicolor dot matrix printing can produce printouts of colored text or simple graphics, but it is not suitable for producing colorful, realistic images. In some models, the possibility of full color printing is realized with the help of additional equipment. Due to the advent of color inkjet printers, which are characterized by much higher performance, dot matrix color printers are practically not used.
