(3) Keyboard. The printer keyboard looks like a typewriter, but is linked to
the computer and this permits communication with the system to enter data or
instructions. It can print 300 characters per minute for letter-quality printing.
(4) The print wheel printer. This type of printer prints a line at a time. It
contains 120 print wheels, one for each of 120 print characters on a line. Each wheel,
in turn, has 48 characters. Each wheel rotates to the desired characters, when all
wheels are in the right position, a hammer drives the paper against the wheels, so that
the entire line is printed at once. This type of printer is relatively slow, with a rate of 150
lines per minute.
e. Non-impact Printers. Non-impact printers are faster and more reliable since
they involve fewer mechanical moving parts. They also offer a wider choice of type
faces and better speed-to-price ratios. While they cannot make carbon copies, they can
make multiple printings of a page in less time than it takes an impact printer to make
one multicarbon page.
(a) Capabilities. Top-quality laser printers print an unlimited variety of
letters, designs, and pictures with almost typeset quality (known as letter-quality). They
use a laser beam to write on a rotating drum that attracts toner, much like a copier.
Laser printers have helped cause a revolution in desk top publishing that has made
newsletters attractive and business reports striking. These printers can produce several
fonts on the same page, and have a speed of 21,000 lines per minute. Laser printers
are often used to print books because of their high quality and versatility. Most people
can't distinguish laser printer output from printed text, although there is a big difference
in resolution (the number of dots per inch). Laser printers run at 300 dots per inch,
while typesetters reach 1200. Low-priced laser printers use the same technology, but
handle fewer fonts and cannot do fancy graphics. They offer more capabilities and
better quality than the popular dot matrix printers that have dominated the market up to
laser: a device capable of producing a narrow beam of high intensity that can
laser printer: a non-impact printer that uses laser beams and
electrophotographic technology to form high-quality images.
(b) Cost. Laser printers produce the nicest results at high speeds. But
up to now, they have been very expensive, starting at 00 and rising to ,000.
Most home and business users try to stay in the 00 to 00 range. As better laser
printers begin to drop in price, more people will buy them. At this writing, a printer that
produces four pages a minute with a list price of
,495 will soon sell for just under