Printers Types

The main printer categories are: - laser printers, ink-jets, dot-matrix, multifunctional, etc. Normally home computer users will use ink-jets as they are relatively cheap but superior in quality to dot-matrix. Laser printers are more expensive and more commonly found in the offices.

Ink-jets(bubble-jets) printers spray ionized tiny drops of ink onto a page to create an image. Almost all ink-jets offer a color option as a standard, in varying degrees of resolution. Ink-jet printers are capable of producing high quality print which almost matches the quality of a laser printer. A standard ink-jet printer has a resolution of 300 dots per inch, although newer models have improved on that. As a rule color link-jet printers can also be used as a regular black and white printer.

Laser printers operate by shining a laser beam to produce an image on a drum. The drum is then rolled through toner, and the electrically charged portions of the drum pick up ink. Finally, using a combination of heat and pressure, the ink on the drum is transferred onto the page. Laser printers produce output at a great speed and with a very high resolution. In terms of speed and image quality they are preferred by experts. Color laser printers use the same toner-based printing process as black and white laser printers, except that they combine four different toner colors. Color laser printers can also be used as a regular black and white laser printer.

LED/LCD printers are types of electro photographic printers that are identical to laser printers in most ways. Both LCD (liquid crystal display) and LED (light-emitting diode) printers use a light source instead of a laser to create an image on a drum. In most contexts, " laser printer" covers LCD and LED printers as well. The print process is almost identical, but LED printers use Light Emitting Diodes to charge the drum, and the other uses Liquid Crystals. These printers produce a very high quality text and graphics print out.

Impact (Dot-matrix) printers use a set of closely spaced pins to print letters or other characters on a page. These printers actually impact the page to print a character, much like a typewriter. Dot-matrix printers vary in terms of speed and the number of pins they have. They can run at a speed anywhere between 50 and 500 cps (characters per second). The number of pins, which can vary between 9 to 24, determines the quality of the print job. Dot matrix printers are commonly used for printing invoices, purchase orders, shipping forms, labels, and other multi-part forms.

Solid Ink printers are page printers that use solid wax ink sticks in a " phase-change" process. Solid-ink printers offer better color consistency than do most technologies, with little variation caused by changes in temperature, humidity, or type of paper. Solid ink machines have better reliability, because they have fewer components in comparison, for example with color laser printers.

Plotters are large-scale printers that are very accurate at reproducing line drawings. They are commonly used for technical drawings.

Digital Photo printers Many middle range printers are now able to print photo quality images. Photo print heads allow a greater resolution to be achieved to improve photo image quality. Photo ink jet printers expand their range by adding additional ink colors, usually light cyan and light magenta.

Network printer is a printer that provides output capabilities to all network users.

Multifunction printers: combine top-quality color ink-jet or laser printing with faxing, color copying and color scanning telephoning - all in one space-saving machine.

EZ CD/DVD Printers: provide a low cost way to create professional printed CD-Rs and DVD-Rs. Instead of writing on the CD or applying labels, you can print directly on the CD surface. With high speed capabilities, a full color image can be printed directly on the top surface of your CDs in less than 1 minute.

3D Printers. The ZPrinter 310 System creates physical models directly from computer-aided design system (“CAD”) and other digital data in hours instead of days. The printer is fast, versatile and simple, allowing engineers to produce a range of concept models and functional test parts quickly and inexpensively. The system is ideal for an office environment or educational institution, providing product developers easy access to a 3D Printer.

The Controller: The page description language

The primary printer languages these days are Hewlett Packard's Printer Command Language (PCL) and Adobe's Postscript. Both of these languages describe the page in vector form -- that is, as mathematical values of geometric shapes, rather than as a series of dots (a bitmap image). The printer itself takes the vector images and converts them into a bitmap page. With this system, the printer can receive elaborate, complex pages, featuring any sort of font or image. Also, since the printer creates the bitmap image itself, it can use its maximum printer resolution.

Some printers use a graphical device interface (GDI) format instead of a standard PCL. In this system, the host computer creates the dot array itself, so the controller doesn't have to process anything -- it just sends the dot instructions on to the laser.

But in most laser printers, the controller must organize all of the data it receives from the host computer. This includes all of the commands that tell the printer what to do -- what paper to use, how to format the page, how to handle the font, etc. For the controller to work with this data, it has to get it in the right order.