Output Devices, ContinuedPrintersImpact printersDot matrixprintersPrinters provide a hard copy printout of data stored electronically inside thecomputer or from a disk. The two types of printers are impact printers andnonimpact printers.Impact printers operate in the same manner as do typewriters. They areeither front striking where a print hammer strikes a character against an inkedribbon and paper or hammer striking where print hammers strike a characteragainst paper first and then an inked ribbon. Impact printers print onecharacter at a time at speeds from 30 to 350 characters per second (CPS).Impact printers use standard single, multipart, and continuous-form paper.Dot matrix printers and daisy wheel printers are impact printers.A dot matrix printer creates a character with a series of tiny pins or wiresthat strike the ribbon or page and leave an image in dots. The resolution ofthe matrix is defined in terms of rows and columns of dots. A 7 by 9 matrixuses seven dots horizontally and nine dots vertically to create a character.Some dot matrix printers have a 36 by 24 matrix. The size of the matrixdetermines the quality of the printed character. Dot matrix printers are nearletter quality, faster than daisy wheel printers, and have speeds ranging from60 to 350 cps.Figure 3-9 shows the letter ‘L’ created by a dot matrix printer,Figure 3-9. —The letter “L” on a dotmatrix printer.Continued on next page3-20
Integrated Publishing, Inc. - A (SDVOSB) Service Disabled Veteran Owned Small Business
