Specifications

■ Multicolor layering. HP inkjet printers use two forms of a process referred to as Photo REt:
• Photo REtII. It places 16 dots of ink in various colors into a single dot; conventional inkjet
printers can place only 8 colors into a single dot.
• Photo REtIII. It is used on most current HP inkjet printer models and uses a five-picoliter
droplet and 29 colors of ink in a single dot to print as many as 3,500 color combinations
per dot using 136 nozzles per each of the three colors in the color cartridge.
■ Reduced ink volume. Even though some inkjet printers of 1997–98 featured print resolutions
comparable to today’s inkjet printers, current models often provide better-looking print quality
because they use less ink per droplet, which is measured in picoliters. The Epson Stylus Photo
870, for example, has the same 1,440×720dpi print resolution as the earlier Epson Stylus Photo
EX, but the Photo 870 uses only 4 picoliters of ink per droplet, compared with the Photo EX’s
11 picoliters per droplet. Other models from Lexmark, Epson, Canon, and Hewlett-Packard have
ink volumes ranging from 7 picoliters to as low as 3 picoliters per droplet, creating pages that
can dry more quickly as well as display finer print details than older printers. An equivalent
amount of ink also lasts longer and brings the cost per page down for newer printers when
compared with older printers that use more ink per printed page.
■ Improved printer-control software. Getting the best results with inkjet printers can be confusing
because of the wide variety of options for paper type, image type, and print resolutions.
Enhanced printer drivers supplied with the newest inkjet printers provide better control with
less possibility of error in printing. Rather than selecting from a variety of print resolutions and
paper types, these printer drivers often provide a few preselected combinations, as well as pro-
vide customization for users with special needs.
Inkjet Limitations
The latest inkjet printers can provide features once found only on laser printers:
■ Full-duplex printing (printing on both sides of the paper) is available with the Hewlett-Packard DeskJet
970Cxi and HP PhotoSmart P1100.
■ Rated black-ink text print speeds exceeding 10ppm, and as high as 13ppm are available from the best
printer models from HP, Epson, Canon, and Lexmark. Although actual real-world performance is far
less, today’s inkjet printers are definitely a lot faster than their predecessors.
These features make inkjet printers, with their combination of black-and-white and color print capa-
bilities, better choices than ever before for more and more SOHO and corporate office users. However,
the biggest problem remains the need for specially coated or designed papers and transparency stocks
to avoid smearing and achieve the high-quality results the printers are designed to produce.
Special inkjet papers can prevent this problem, but they are more expensive and offer far less variety
than the laser printer papers on the market.
Inkjet printers also must use special transparency stock with a roughened (sandpaper-like) surface to
promote proper ink drying. The extra cost of special paper and other print media, along with the rela-
tively high cost and limited print life of inkjet cartridges, makes them a high cost-per-page type of
printing. Figure 7 illustrates Canon’s four-layer paper, which is ideal for inkjet printing.