Inkjet v Laser

What people are interested in is the quality of the image on the page and from this point of view inkjets can generally outperform laser printers. The quality of an image is partly how fine the lines can be and partly the range of colours.

Inkjets can produce finer dots on the page - down to a resolution of 9,600 dots per inch using very fine nozzles. The inkjet droplet is self-contained because of the surface tension in the liquid ink. Inkjets might give some control of drop size helping to produce a wider colour gamut. All laser printers and many inkjets use four colours but because the inkjet head is a relatively cheap component there is nothing to stop manufacturers adding red, green, orange and even white and gloss printheads to achieve particular looks. One problem is that the ink is wet and to prevent bleeding of the image due to runny ink a really good looking picture needs special inkjet paper. There were problems with dyes fading in sunlight. Most manufacturers now promise pictures will be fade free for many years if they are printed on their own brand of paper and kept under glass. Ordinary office documents usually don't need special paper but inkjet printout smears if it gets wet or even when handled with damp hands.

Laser printers struggle to give an engine resolution beyond 1200 dpi. The image is made from small particles of toner moved by electrostatic fields and if the fields are made very small they will tend to overlap. Image resolution might seem a limitation but the human eye struggles to resolve anything as small as 1/50th of a millimetre. Most professional printing is at 300dpi. It doesn't seem practical to make a laser with multiple colours - red, green, orange and grey toners are unknown at present.

Printers use their actual resolution and a combination of greyscale and a dither pattern to achieve their apparent resolution. This gives printer makers the opportunity to claim their machines have "FastRes 1200" and "ImageRet 3600" which look like resolutions but are surrogates meaning print quality. Recent colour laser printers give pictures as good as those in glossy magazines.

Laser printer pictures look good on ordinary office copier paper. The paper may yellow over time, using inkjet paper might avoid this. Laser toner colourant is fairly stable although as with many plastics the reds tend to fade if they are left in bright sunlight without a glass cover.

Print speed is often important. Laser printers tend to be faster than inkjets. Once the laser printer is in motion the mechanism will normally proceed at its rated speed in pages per minute. Most inkjets scan their heads back and forth across the page and whilst they might achieve 20-30 pages per minute in draft speed they usually slow down to 3-5 page per minute when asked for a good quality image. Some recent inkjets like the HP Edgeline series (CM8060) achieve high speeds using a big pagewidth head with more than 10,000 nozzles. That probably stretches the limits of reliability for office and home use.

Laser printers tend to score well on reliability. The laser mechanism is complicated but most of the processes are shafts and rollers turning in a continual action. There is a lot to go wrong in a laser printer but it doesn't go wrong much. The majority of laser printer faults can be cleared by cleaning the machine and replacing one or two parts. Larger office laser printers are usually made to be repairable and spares are available.

Inkjets have a reliability issue. The problem is not so much the printer as the users. People expect a printer to burst into life when it is wanted after the printer has sat unused for months. Too often one or more of the heads will have dried out. Most printers offer a range of purge routines that attempt to recover the heads but this can be expensive in ink, tedious to deal with and too often unsuccessful. If you won't be using a printer often then either buy a cheap inkjet with disposable cartridges and a spare - or go for a laser printer.

Both inkjet and laser mechanisms have long antecedents but essentially emerged as new products in the mid 1980s. Laser printers were adopted by Apple to match the new graphical capabilities of their "Mac" product line. HP introduced a laser printer to provide quick, high quality output for office word processing. Both used a Canon engine. HP and Canon also introduced inkjet printers offering graphical capabilities at a low price. It's worth noting that until that time HP was largely a large laboratory instrument maker with an interest in computers and over the next few years they sold a million laser printers and changed business direction.