-: Printer :-
A printer is an output device that produces text and graphics on
paper.
Types of
printer Printers
There Have 2 Types Of Printer
1)
Impact printer
2)
Non-impact
printer
Impact printer produces text and images when tiny wire pins on
print head strike the ink ribbon by physically contacting the paper. Non-impact
printer produces text and graphics on paper without actually striking the
paper.
Printers can also be categorized based on the print method or
print technology. The most popular ones are inkjet
printer*, *laser printer*, *dot-matrix printer and *thermal printer*. Among these,
only dot-matrix printer is impact printer and the others are non-impact
printers.
Some printers are named because they are designed for specific
functions, such as photo
printers*, *portable printers and all-in-one / *multifunction printers*. Photo
printers and portable printers usually use inkjet print method whereas
multifunction printers may use inkjet or laser print method
Inkjet printers and laser printers are the most popular printer
types for home and business use. Dot matrix printer was popular in 70's and
80's but has been gradually replaced by inkjet printers for home use. However,
they are still being used to print multi-part forms and carbon copies for some
businesses. The use of thermal printers is limited to ATM, cash registers and
point-of-sales terminals. Some label printers and portable printers also use
thermal printing.
Due to the popularity of digital camera, laptop and SoHo office
(small office / home office), the demand for photo printers, portable printers
and multifunction printers has also increased substantially in recent years.
h1. Inkjet Printers Inkjet printers are non-impact printers which
print text and images by spraying tiny droplets of liquid ink onto paper. They
are the most popular printers for home use.
Currently, most inkjet printers use either thermal inkjet or
piezoelectric inkjet technology. Thermal inkjet printer uses heating element to
heat liquid ink to form vapor bubble, which forces the ink droplets onto the
paper through the nozzle. Most inkjet manufacturers use this technology in
consumer inkjet printers.
Piezoelectric inkjet technology is used on all Epson printers and
industrial inkjet printers. Instead of using heating element, these printers
use a piezoelectric crystal in each nozzle. The piezoelectric crystal changes
shape and size based on the electric current received, and forces tiny droplets
of ink onto the paper from the nozzle.
Thermal inkjet printers use aqueous ink which is a mixture of
water, glycol and dyes. These inks are inexpensive but they can only be used on
paper or specially coated materials. Piezoelectric inkjet printers allow the
use of a wider range of inks, such as solvent inks, UV-curable inks, dye
sublimation inks, and can print text and graphics on different uncoated
materials.
The inkjet head design is also divided into two main groups:
fixed-head and disposable head. Fixed-head is built into the printer and should
last for the whole life of the printer. It produces more accurate output than
cheap disposable head. The ink cartridges for fixed head printers are also
cheaper as the print head does not need to be replaced. However, if the head is
damaged, the entire printer has to be replaced.
Disposable head is included in replacement ink cartridge. It is
replaced each time an ink cartridge runs out of ink. This increases the cost of
ink cartridges and also limits the use of high quality print head in these
cartridges. However, a damaged print head is not a problem as one can easily
replace it with a new ink cartridge.
Some printer manufacturers use disposable ink and disposable print
head separately. The print head can last much longer than cheap disposable head
and is suitable for high volume printing. However, it can also be replaced
easily if the head is clogged or damaged.
Although inkjet printers are generally used in home and small
businesses, some manufacturers, such as Hewlett Packard, have produced high end
inkjet printers for industrial use. These professional inkjet printers are
usually used to print advertising graphics or technical drawings.
Advantages of inkjet printers:
1) Low cost
2) High quality of output, capable of printing fine and smooth
details
3) Capable of printing in vivid color, good for printing pictures
4) Easy to use
5) Reasonably fast
6) Quieter than dot matrix printer
7) No warm up time
Disadvantages of inkjet printers:
1) Print head is less durable, prone to clogging and damage
2) Expensive replacement ink cartridges
3) Not good for high volume printing
4) Printing speed is not as fast as laser printers
5) Ink bleeding, ink carried sideways causing blurred effects on
some papers
6) Aqueous ink is sensitive to water, even a small drop of water
can cause blurring
7) Cannot use highlighter marker on inkjet printouts
Many consumer inkjet printers are selling at very low price (under
$100) these days. It is the printer manufacturer's marketing strategy to reduce
the price of the printers but dramatically mark up the price of replacement
cartridges. However, consumers still have the options to buy cheap compatible
and remanufactured inkjet cartridges or ink refill kits to cut down printing
cost.
h1. Laser Printers Laser printers are non-impact printers which
can print text and images in high speed and high quality resolution, ranging
from 600 to 1200 dpi.
Unlike inkjet printers, laser printer use toner (black or colored
powder) instead of liquid inks. A laser printer consists of these major
components: drum cartridge, rotating mirror, toner cartridge and roller. The
drum cartridge rotates as the paper is fed through. The mirror deflects laser
beam across the surface of the drum. Laser beam creates charge that causes the
toner to stick to the drum. As the drum rotates and presses on paper, toner is
transferred from the drum to paper, creating images. Rollers then use heat and
pressure to fuse toner to paper. Colored laser printers add colored toner in
three additional passes.
Advantages of laser printers:
1) High resolution
2) High print speed
3) No smearing
4) Low cost per page (compared to inkjet printers)
5) Printout is not sensitive to water
6) Good for high volume printing
Disadvantages of laser printers:
1) More expensive than inkjet printers
2) Except for high end machines, laser printers are less capable
of printing vivid colors and high quality images such as photos.
3) The cost of toner replacement and drum replacement is high
4) Bulkier than inkjet printers
5) Warm up time needed
h2. Dot-matrix printer Dot-matrix printer is an impact printer
that produces text and graphics when tiny wire pins on the print head strike
the ink ribbon. The print head runs back and forth on the paper like a
typewriter. When the ink ribbon presses on the paper, it creates dots that form
text and images. Higher number of pins means that the printer prints more dots
per character, thus resulting in higher print quality.
Dot-matrix printers were very popular and the most common type of
printer for personal computer in 70's to 80's. However, their use was gradually
replaced by inkjet printers in 90's. As of today, dot matrix printers are only
used in some point-of-sales terminals, or businesses where printing of carbon
copy multi-part forms or data logging are needed.
Advantages of dot matrix printer:
1) Can print on multi-part forms or carbon copies
2) Low printing cost per page
3) Can be used on continuous form paper, useful for data logging
4) Reliable, durable
Disadvantages of dot matrix printer:
1) Noisy
2) Limited print quality
3) Low printing speed
4) Limited color printing
h2. Thermal printers Thermal printers use two types of printing
technologies: direct thermal and thermal
transfer printing.
Traditional thermal printers use direct thermal method by pushing
electrically heated pins against heat-sensitive paper (thermal paper). The
coating on the thermal paper turns black in the areas where it is heated,
producing characters or images. Direct thermal printers have no ink, toner or
ribbon. These printers are durable, easy to use and cost less to print than
other printers. However, the thermal paper is sensitive to heat, light, water,
and abrasion and the text and images may fade over time.
In thermal transfer printing, a thermal print head applies heat to
a heat-sensitive ribbon, which melts ink onto paper and a wide range of
materials to form text and images. The printouts can be extremely durable and
can be stored over long period of time
Thermal printers are often used in cash registers, ATM and
point-of-sales terminals. Direct thermal printing was used in some older fax
machines before the 21^st^ century. However, these old models are now replaced
by new machines which use laser and inkjet printing. Thermal printing is still
considered as the best technology for bar code printing because it produces
accurate, high quality images with exact bar widths. Some portable printers and
most label printers still use thermal printing method.
Thermal printer is not the same as thermal inkjet printer. The
latter uses inkjet print technology by heating liquid ink to form vapor bubble,
which forces the ink droplet onto the paper from the nozzle.
h1. Specialty Printers h2. Photo printer Photo printers are color
printers that produce photo lab quality pictures on photo paper. They can also
be used to print documents. These printers have a very high number of nozzles
and can print very fine droplets for improved image quality.
Some photo printers also have media card readers. They can print
4" x 6" photos directly from the media card of digital cameras
without a computer in between.
Theoretically, most inkjet printers and high end laser printers
are capable of printing high quality pictures. Sometimes, these printers are
marketed as "photo printers". However, a dedicated photo printer is
designed to print photos effectively and economically. Apart from a higher
number of nozzles and very fine droplets, these printers also use additional
cartridges, such as photo cyan, light magenta and light black. These additional
color cartridges allow the printing of more vivid and realistic photos and the
result is better than ordinary inkjet and laser printers.
h2. Portable printer Portable printers are small, lightweight
inkjet or thermal printers that allow computer users to print from laptop
computers when traveling. They are easy to carry, convenient to use but
generally more expensive than normal inkjet printers due to the compact design.
Their printing speed is also lower than normal printers. Some portable printers
are designed to print photos immediately from digital cameras and are known as
portable photo printers.
h2. MultiFunction / All-in-One Printers Multifunction printer
(MFP) is also known as all-in-one printer or multifunction device (MFD). It is
a machine that includes several functionalities including printer, scanner,
copier and fax.
Multifunction printer is very popular in SoHo (small office / home
office) offices. It can use either inkjet or laser print method. Some multifunction
printers also have media card readers, allowing printing of pictures directly
from digital cameras without using a computer.
Advantages of multifunction printers:
1) Low cost - it is often cheaper to buy a multifunction printer
than individual components (fax machine, scanner, printer, copier) separately
2) Take up less room
Disadvantages of multifunction printers:
1) If one component is broken, the entire machine has to be
replaced
2) Failure in any component will affect other functions
3) The print quality and speed may be lower than some stand alone
components
