Computer Printer Evolution
Since English inventor Charles Babbage created the first mechanical computer printer in 1849 – which was used to print the results of calculations from his Difference Engine – a multitude of technologies have been developed off the back of it, all chasing the ideal of the perfect print.
While further mechanical printers were designed and manufactured throughout the late-i9th and early-20th centuries, the transition from purely mechanical to mechanical-electrical systems did not arise until the early-Fifties. It was at this point that the first high-speed, non-fluid printer was made by Remington Rand for use with the UNI VAC computer – the first to be commercially produced in the USA.
This was almost immediately followed by two new printing mechanisms – dot matrix and dye sublimation – entering the mainstream market. Dot-matrix printers work by impacting sheets of paper with tiny metal rods, with an inked ribbon sandwiched between the two.
Each rod is driven forward by a tiny electromagnet (or solenoid) and, along with the horizontal/vertical movement of a print head, allowed characters to be generated out of a series of impacted dots. Dye-sublimation printers, on the other hand, work by transferring dyes held in coloured cellophane ribbons onto a material through controlled heating. The term sublimation is used as during the printing process the held dye transitions between a solid state to a gas without passing through a liquid stage.
While dot-matrix and dye-sublimation printers are still used today, they are much more limited. This is due to the invention of both laser and inkjet printers, which offer faster and higher-fidelity results – the former first entering the market in 1977. Laser printers, such as the Xerox 9700 – which was the first to be commercially available, work by a process called xerography, which was originally demonstrated by American inventor Chester Carlson in 1938. Xerography is a dry printing technique (ie chemicals are not used) where a negative image is formed of the desired print via the use of resinous powder (toner) on an electrically charged drum. The powder sticks to the charged regions of the drum and is then transferred to paper by roller heating, fusing the carbonpolymer powder to the surface.
Inkjet printers, meanwhile – which today are the most common form of consumer computer printer – were taken up on a mass-market scale back in 1988; the HP Deskjet was the market standard. Inkjets work by propelling ink contained within a cartridge through a print head – commonly also installed in the cartridge – onto a sheet of paper. There are two main types of technology used in modern inkjet printers: continuous (CIJ) and drop-on-demand (DOD). As the names suggest, continuous inkjets deposit ink from a cartridge in a constant stream – albeit broken into droplets at regular intervals, while drop-on-demand inkjets use electrical pulses to pressure-squeeze individual ink droplets out of a print head nozzle onto the paper.
1959 – Xerox 914 – The first automatic office copier that can replicate material on plain paper is launched. The unit weighs 294 kilograms (648 pounds), measures over a metre (3.3 feet) in all dimensions and can produce just one copy per 26 seconds
1977 – Xerox 9700 – Xerox launches the first commercial xerographic laser printer. The 9700 could operate at two pages per second and had raster font selection and form generation capabilities. It becomes an industry standard.
1980 – Epson MX-80 – A ground breaking dot-matrix printer, the MX-80 is the first to combine affordability with print quality in a home setting. Despite its low dot density (60dpi horizontal, 72dpi vertical) it sparks worldwide interest in impact printing.
1984 – HP LaserJet – The first desktop laser printer, the LaserJet is introduced for USD 3,500. Its print cartridge outputs eight pages of text and/or graphics per minute. It’s also one of the first printers to be near silent when in operation.
1988 – HP DeskJet – The first mass-market inkjet arrives. At USD 1,000, it is the least expensive non-impact printer on the market. Key to its uptake is its cheap, disposable print head included in each ink cartridge.
1994 – Epson Stylus Color – Epson releases the Stylus Color, the first to bring 720dpi hi-res (for the time) printing to the desktop environment. It has revolutionary Micro Piezo inkjet tech, where piezoelectric actuators are built in to the print nozzles. Below is the 777 model in the series.
2011 – Kodak HERO – Kodak launches its HERO range of all-in-one printers. Key to their rapid adoption is both their integration of cloud computing features – such as Google Cloud Print – and also their steep reduction in ink cartridge costs.