Non-impact Dot matrix printers

Dot matrix charactesr are built by printing some dots which forms a letter, number or symbol. Dots are generated by two methods- impact print method and non impact print method. Here printing of characters occurs when one of the ASCII codes is signaled and controlled by the read only memory (ROM) chip. Non-impact Dot matrix printers cause a mark without directly touching the paper. But making carbon copies is impossible here. But this type of printer is extremely useful for printing single copies of computer output, for recording the output of printing calculators, video displays and for logging industrial data. There are 4 types of Non-impact Dot matrix printers. They are thermal, electro sensitive, electrostatic and ink jet.