DOT matrix1.The termDOT matrixrefers to the process of placingdotsto form an image; the quality of the image being determined by thedots per inch.2.Alternatively referred to as apin printer,Dot matrix printerswere first introduced byCentronicsin1970and is aprinterthat uses print heads to shoot ink or strike an ink ribbon to place hundreds to thousands of little dots to form text or images. Today, Dot matrix printers are rarely used or found because of the low quality print outs when compared toink jet printersandlaser printers.A type ofprinterthat producescharactersand illustrations by strikingpinsagainst an ink ribbon to print closely spaceddotsin the appropriate shape. Dot-matrix printers are relatively expensive and do not produce high-qualityoutput. However, they can print to multi-page forms (that is, carbon copies), something laser and ink-jet printers cannot do.Dot-matrix printers vary in two important characteristics: speed:Given incharacters per second(cps),the speed can vary from about 50 to over 500 cps. Most dot-matrix printers offer different speeds depending on the quality of print desired. print quality:Determined by the number of pins (the mechanisms that print the dots), it can vary from 9 to 24. The best dot-matrix printers (24 pins) can produce near letter-quality type, although you can still see a difference if you look closely.In addition to these characteristics, you should also consider the noise factor. Compared tolaserandink-jet printers, dot-matrix printers are notorious for making a racket.PrinterAprinteris anexternalhardwaredevice responsible for taking computer data and generating ahard copyof that data. Printers are one of the most used peripherals on computers and are commonly used to print text, images, and photos. The picture is theLexmarkZ605Inkjet printerand an example of a computer printer.Laser printerFirst developed atXerox PARCbyGary Starkweatherand released in1971, alaser printeris a printer that utilizes laser technology to print images on the paper. Laser printers are often used in corporate, school, and other environments that require print jobs to be completed quickly and in large quantities. The picture is an example of what a laser printer may look like. This picture is of theLexmarkC782n laser printer and as can be seen much larger than an ink jet printer found in most homes. Finally, below is a chart of the steps a laser printer takes to print.Laser printer printing stepsCleaningRemoves prior image information and toner from thedrum.ConditioningApplies a uniform negative charge to thedrum.WritingLight source such as lasers,LED, or LCS (Liquid Crystal Shutter) write to areas on the drum discharging the negative potential where it hits.DevelopingThe toner is ionized with a negative charge and is attracted to the areas previously written (discharged) on the drum.TransferThe toner of the drum is transferred to the paper by either a positively ionized field (created by a transfer corona wire) or by a transfer roller in newer printers. The toner is not yet permanently set on the paper and requires the last stage.FusingHeat and pressure are applied to the paper and toner. The toner melts and then is pressed to the paper like doing an iron-on transfer to a T-shirt.Thermal printer1.Athermal impact printerorelectrothermal printeris a printer that uses heated pins to "burn" images onto heat-sensitive paper. These printers are commonly used in calculators and fax machines; and although they are inexpensive and print relatively fast, they produce low resolution print jobs.2.Athermal printer,thermal transfer printer, orthermal wax-transfer printeris a high quality printer invented byJack Kilbythat commonly utilizes a thermal wax ribbon that melts a colored wax onto the paper creating near photo-realistic images.Related pagesThermal printer1.Athermal impact printerorelectrothermal printeris a printer that uses heated pins to "burn" images onto heat-sensitive paper. These printers are commonly used in calculators and fax machines; and although they are inexpensive and print relatively fast, they produce low resolution print jobs.2.Athermal printer,thermal transfer printer, orthermal wax-transfer printeris a high quality printer invented byJack Kilbythat commonly utilizes a thermal wax ribbon that melts a colored wax onto the paper creating near photo-realistic images.

Computer printer help and supportLED PrinterSimilar to alaser printer,LED printersare non-impact but use a light-emitting diode instead of a laser in the printhead. LED printers were originally developed byCasioand function by focusing light across the entire length of the drum, thus creating areas that are less charged, which attracts toner. The printer then transfers the toner from the drum to the paper and applies intense heat to fuse the toner to the paper.There are many advantages to owning and LED printer vs. the conventional laser printer, including higher efficiency and reliability, due to their having fewer parts and no moving parts in the printhead.