For a device that often gets taken for granted (when was the last time you were excited to get a new printer, like you’re excited when you buy a new smartphone or HDTV?), the computer printer has a fairly interesting history, and similar to the computer mouse, the technology behind it has always been more advanced and complex than you would think.
The first computer printer to be invented is thought to be the printer that Charles Babbage originally planned to be included with his difference engine, a primitive computer (Wikipedia calls it an “automatic mechanical calculator designed to tabulate polynomial functions”) that Babbage designed in the mid-1800s, though a working model of it was never actually built until more than 150 years later in the year 2000.
Another early predecessor to the computer printer was a telegraph machine, the Syphon Recorder, invented by Lord Kelvin in 1858. This machine converted telegraph signals into a squiggly line written in ink (kind of like an earthquake seismometer). Each different letter created a unique shape on the line, so that a telegraph operator could interpret and convey the message, even if the operator wasn’t sitting at the machine at the time when the message was originally transmitted.
General purpose electrical computers were first developed in the 1940s, 1950s, and 1960s. The printers for these computers were mainly electronic typewriters or computer-specific printers called line printers, which work in a similar way to typewriters, in that they press ink onto a piece a paper using a combination of an ink ribbon and raised metal type. With line printers, the paper lays on top of a metal cylinder covered in raised type, with the ink ribbon between the paper and the cylinder.
Line printers work in a similar way to typewriters, in that they press ink onto a piece a paper using a combination of an ink ribbon and raised metal type. With line printers, the paper lays on top of a metal cylinder covered in raised type, with the ink ribbon between the paper and the cylinder.
To imprint a character, a hammer (not a hammer you buy at the hardware store, but a small, blunt, mechanically-driven piece of metal) on the other side of the piece of paper strikes the piece of paper onto the appropriate raised type (usually, the cylinder will have dozens of rows on it, and each row will repeat the same character for the entire length of the row, and the cylinder will automatically spin to put the correct character into place for the hammer to strike) and onto the appropriate place on the line of paper.
Dot matrix printers were the next type of computer printer to develop after line printers. Dot matrix printers are similar to line printers in that they are both “impact” printers that produce text on a piece of paper by forcefully pushing ink onto the paper with a blunt metal part. Dot matrix printers, however, do not use hammers or raised type; instead, they generate text by pushing small (blunt) pins onto an ink ribbon that is laid over the paper.
Because they didn’t use raised type, dot matrix printers could print images and support any font. The text that they produced was also cleaner and bolder than that of line printers, though at a cost of speed (Dot matrix printers can print up to 1,000 characters per minute, and line printers can printer up to 1,200 lines per minute)
Dot matrix printers were the computer printer of choice for most businesses and consumers from the 1970s until well into the 1990s.
The first functional versions of two types of non-impact computer printers, laser printers, were manufactured in the 1970s.
Ink jet printers were developed simultaneously by the R&D departments at multiple companies, including Canon and HP. The first consumer-oriented version of an ink jet printer, the HP DeskJet, wasn’t released until 1988, and cost $1,000 at the time. Ink jet printers work by releasing tiny droplets of liquid ink using heat or electricity, from cartridges that cost more than their weight in gold. These days, most computer printers owned by consumers are ink jet printers, they are cheap to buy and cheap to run if you use them infrequently.
The laser printer, meanwhile, was developed by Gary Starkweather in 1971 at (where else) the Xerox Palo Alto Research Center, or Xerox PARC. The laser printer works by projecting a laser onto a light-sensitive cylinder, where the document to be printed is “drawn.” The piece of paper is then guided under the cylinder, and the cylinder releases toner (powdered ink) onto the paper (releasing it in the pattern designated by the laser) as it slides through.
These days most computer printers used by businesses are laser printers. Laser printers tend to be more expensive than ink jet printers, but they also tend to print large quantities of copies faster than ink jets and produce higher quality prints.
The dot matrix printer still lives on at some businesses, however, since they are the default printing device of many old cash registers, and because some businesses (like car dealerships and physicians’ offices) still need an impact printer for their multi-copy, carbon paper documents.
Looking ahead, many expect the computer printer to become more of a niche device, like the fax machine, because most documents these days are sent and viewed electronically.
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