Choose a Printer: Impact Printers

What impact printers are good for

In this section, we'll discuss three types of printers: line matrix, serial dot matrix, and band printers, all of which are frequently lumped together as "impact" printers. While there are many similarities among these technologies, there are as many differences.

Band printers

Band printers impact the paper the same way typewriters do - with fully formed embossed characters like you'd find on the ball of an old Selectric typewriter. This approach prohibits band printers from printing graphical output or varying the size of a printed character. As a result, the use of band printers has decreased dramatically. Since band printers just aren't used that much anymore.

Line matrix printers

While line matrix and serial dot matrix printers both form characters by impact printing of dots, they too, have very little else in common. Line matrix printers print the dot arrays for their characters by moving the paper vertically past a hammerbank, which shuttles back and forth horizontally across a small space. Since the hammers in the bank cover the full line width, the shuttle motion makes one row of dots in each character array to be printed on the line. As the paper moves upward, the print head progressively builds these rows of dots from top to bottom of the characters. When all the rows have been formed, the cycle is complete and a full line of characters has been printed. Then the paper moves down to the next line and the array-forming cycle is repeated.

Serial dot matrix printers

In contrast, serial dot matrix printers use a moveable print head, which has an array of pins. The print head moves horizontally across the paper and prints characters - one at a time - to complete the line. Then the paper advances and characters are again printed horizontally across the page. Because of their design differences, line matrix printers are much faster than serial dot matrix printers, and their print mechanisms are far more reliable. Both line matrix and serial dot matrix printers produce dots that are larger than those produced by laser and thermal technologies, dot spacing being in the range of 100 to 200 dpi.

Line matrix printers are cost effective

The visual quality of line matrix text and graphical output is, as you would expect, not as crisply defined as laser or thermal output. However, on a cost per page basis, line matrix printers are a much less expensive way to print a page. For many applications, the quality of line matrix printing meets all the requirements. With their wide carriage capabilities, line matrix printers are highly versatile - printing MIS reports, labels, shipping tickets, invoices, production tags, just about anything.

Print multi-part forms with dot matrix printers and line printers

Naturally dot matrix printers and line printers (both considered "impact printers") are the only game in town when it comes to printing multi-part forms. The non-impact technologies, such as laser and thermal, cannot make multiple copies in one pass. Line matrix printers use inexpensive ribbons and are great for long, unattended print runs. These printers are highly robust and print comfortably at high speeds for long periods of time.

Impact printers well suited for industrial applications

They are commonly used in industrial applications and last for many years. They are well-suited to printing in harsh environments, like factories and loading docks. Line matrix printers are superior in handling complex forms and they can print on a very broad range of materials.

Dot matrix printer or line matrix printer

The serial dot matrix printer's advantage is that it provides useful, low volume impact printing. While serial matrix printer purchase prices are usually lower than line matrix printers, they are not nearly as reliable, have lower duty cycles, and their ribbons are more expensive.

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