CS 30 Introduction to Information Technology: PRINTER: Dot Matrix Printer

Wednesday, August 5, 2009

PRINTER: Dot Matrix Printer

Image source: http://www.epson.co.nz/img/products/lq300plusII_600.jpg

A DOT MATRIX PRINTER, also known as an impact matrix printer, works similar to a ribbon typewriter where pressure is applied to an ink source, an ink-soaked cloth ribbon in this case, onto the paper to leave an imprint. The ink transfers to the paper as a dot which combines to form recognizable characters. [1]

Image source: http://www.tech2u.com.au/training/tech2u/introcomp/images/printer02.gif

This technology was invented by Zerillo, Samuel D. (Nashua, NH) and patented in March 25, 1980 the technology under this abstract:

A printer having at least one reciprocally mounted printing member controlled to impact against a printing surface by selective energization of an associated printing driving member. The forward end of the member is guided by a bearing. Ink from a supply source is directed to the printing member near the forward end of the printing member whereby the ink is drawn into the region between the guide hole in the printing member guide bearing and the periphery of the printing member to be moved to the region in front of the forward tip of the printing member whereby activation of the driving member abruptly moves the printing member in the forward printing direction causing the ink deposited upon the tip of the printing member to be urged toward and against the ink receiving medium to transfer the ink to the ink receiving medium. A group of printing members may be used to print in this manner to collectively form characters, symbols, and even graphic patterns. [2]

Image source: http://content.answers.com/main/content/img/CDE/DOTMTRX.GIF

The dots are produced by a tiny metal rod, also called a "wire" or "pin", which is pushed by a tiny electromagnet or solenoid, either directly or through small levers called pawls. The moving portion of the printer is called the print head.

Because of the expiration of Hewlette-Packard’s patents on the inkjet, which was superior to the dot matrix printer, the dot matrix printer was surpassed in usage.

Image source: http://www.noiseaddicts.com/wp-content/uploads/2009/06/dot-matrix-printer.jpg

Currently, Some companies, such as WeP Peripherals, Epson, Okidata, Olivetti, Lexmark, TallyGenicom, as well as OKI Printing Solutions [3] still produce the older models of printers although it is more expensive.

Image source: http://itblogs.in/files/media/dot-matrix-printer.GIF

Because of the pressure applied to the paper, this style of printing can create carbon copies with the use of carbon paper or carbonless copies which is similar to the receipt paper that leaves a mark on the paper when scratched. Most other printers do not make use of pressure to print and not leave a mark if printed with carbon paper. In addition to this, they have one of the lowest printing cost per page.

Unfortunately, the mechanical nature of this type of printer makes it relatively noisier than others. Also, this type of printer can only print low-resolution graphics and have limited quality. The loading of the paper is also time-consuming for low quantities. [1]

The dot matrix printer is used for printing with limited quality and for low cost. It also has the additional function of making carbon copies and carbonless copies. It has very little future prospects other than as a cost effective alternative to printing, but as soon-to-be obsolete piece of equipment because of its mechanical nature, it can always be a paperweight, scrap or antique decoration.