<s>
Dot	B-General_Concept
matrix	I-General_Concept
printing	O
,	O
sometimes	O
called	O
impact	O
matrix	O
printing	O
,	O
is	O
a	O
computer	O
printing	O
process	O
in	O
which	O
ink	O
is	O
applied	O
to	O
a	O
surface	O
using	O
a	O
relatively	O
low-resolution	O
dot	B-General_Concept
matrix	I-General_Concept
for	O
layout	O
.	O
</s>
<s>
Dot	B-General_Concept
matrix	I-General_Concept
printers	O
typically	O
use	O
a	O
print	O
head	O
that	O
moves	O
back	O
and	O
forth	O
or	O
in	O
an	O
up-and-down	O
motion	O
on	O
the	O
page	O
and	O
prints	O
by	O
impact	O
,	O
striking	O
an	O
ink-soaked	O
cloth	O
ribbon	O
against	O
the	O
paper	O
,	O
much	O
like	O
the	O
print	O
mechanism	O
on	O
a	O
typewriter	O
or	O
line	O
printer	O
.	O
</s>
<s>
However	O
,	O
a	O
dot	B-General_Concept
matrix	I-General_Concept
printer	O
is	O
able	O
to	O
print	O
arbitrary	O
patterns	O
and	O
not	O
just	O
specific	O
characters	O
.	O
</s>
<s>
The	O
perceived	O
quality	O
of	O
dot	B-General_Concept
matrix	I-General_Concept
printers	O
depends	O
on	O
the	O
vertical	O
and	O
horizontal	O
resolution	O
and	O
the	O
ability	O
of	O
the	O
printer	O
to	O
overlap	O
adjacent	O
dots	O
.	O
</s>
<s>
Dot	B-General_Concept
matrix	I-General_Concept
printing	O
is	O
typically	O
distinguished	O
from	O
non-impact	O
methods	O
,	O
such	O
as	O
inkjet	O
,	O
thermal	O
,	O
or	O
laser	O
printing	O
,	O
though	O
they	O
too	O
may	O
use	O
a	O
bitmap	O
to	O
represent	O
the	O
printed	O
work	O
.	O
</s>
<s>
Between	O
1952	O
and	O
1954	O
Fritz	O
Karl	O
Preikschat	O
filed	O
five	O
patent	O
applications	O
for	O
his	O
teletype	O
writer	O
7	O
stylus	O
35	O
dot	B-General_Concept
matrix	I-General_Concept
aka	O
PKT	O
printer	O
,	O
a	O
dot	B-General_Concept
matrix	I-General_Concept
teletypewriter	O
built	O
between	O
1954	O
and	O
1956	O
in	O
Germany	O
.	O
</s>
<s>
Like	O
the	O
earlier	O
Hellschreiber	O
,	O
it	O
still	O
used	O
electromechanical	O
means	O
of	O
coding	O
and	O
decoding	O
,	O
but	O
it	O
used	O
a	O
start-stop	O
method	O
(	O
asynchronous	O
transmission	O
)	O
rather	O
than	O
synchronous	B-Protocol
transmission	I-Protocol
for	O
communication	O
.	O
</s>
<s>
An	O
improved	O
transistorized	O
design	O
became	O
the	O
basis	O
for	O
a	O
portable	O
dot	B-General_Concept
matrix	I-General_Concept
facsimile	O
machine	O
,	O
which	O
was	O
prototyped	O
and	O
evaluated	O
for	O
military	O
use	O
by	O
Boeing	O
around	O
1966	O
–	O
1967	O
.	O
</s>
<s>
IBM	O
marketed	O
its	O
first	O
dot	B-General_Concept
matrix	I-General_Concept
printer	O
in	O
1957	O
,	O
the	O
same	O
year	O
that	O
the	O
dye-sublimation	O
printer	O
entered	O
the	O
market	O
.	O
</s>
<s>
In	O
1968	O
,	O
the	O
Japanese	O
manufacturer	O
OKI	O
introduced	O
its	O
first	O
serial	O
impact	O
dot	B-General_Concept
matrix	I-General_Concept
printer	O
(	O
SIDM	O
)	O
,	O
the	O
OKI	O
Wiredot	O
.	O
</s>
<s>
In	O
1970	O
Digital	O
Equipment	O
Corporation	O
(	O
DEC	O
)	O
introduced	O
an	O
impact	O
dot	B-General_Concept
matrix	I-General_Concept
printer	O
,	O
the	O
LA30	O
,	O
as	O
did	O
Centronics	O
(	O
then	O
of	O
Hudson	O
,	O
New	O
Hampshire	O
)	O
:	O
the	O
Centronics	O
101	O
.	O
</s>
<s>
In	O
the	O
process	O
,	O
they	O
designed	O
the	O
parallel	B-Device
electrical	I-Device
interface	I-Device
that	O
was	O
to	O
become	O
standard	O
on	O
most	O
printers	O
until	O
it	O
began	O
to	O
be	O
replaced	O
by	O
the	O
Universal	B-Protocol
Serial	I-Protocol
Bus	I-Protocol
(	O
USB	B-Protocol
)	O
in	O
the	O
late	O
1990s	O
.	O
</s>
<s>
In	O
the	O
1970s	O
and	O
1980s	O
,	O
dot	B-General_Concept
matrix	I-General_Concept
printers	O
were	O
generally	O
considered	O
the	O
best	O
combination	O
of	O
expense	O
and	O
versatility	O
,	O
and	O
until	O
the	O
1990s	O
they	O
were	O
by	O
far	O
the	O
most	O
common	O
form	O
of	O
printer	O
used	O
with	O
personal	B-Device
and	O
home	O
computers	O
.	O
</s>
<s>
Dot	B-General_Concept
matrix	I-General_Concept
printing	O
uses	O
a	O
print	O
head	O
that	O
moves	O
back-and-forth	O
,	O
or	O
in	O
an	O
up-and-down	O
motion	O
,	O
on	O
the	O
page	O
and	O
prints	O
by	O
impact	O
,	O
striking	O
an	O
ink-soaked	O
cloth	O
ribbon	O
against	O
the	O
paper	O
,	O
much	O
like	O
the	O
print	O
mechanism	O
on	O
a	O
typewriter	O
.	O
</s>
<s>
However	O
,	O
unlike	O
a	O
typewriter	O
or	O
daisy	O
wheel	O
printer	O
,	O
letters	O
are	O
drawn	O
out	O
of	O
a	O
dot	B-General_Concept
matrix	I-General_Concept
,	O
and	O
thus	O
,	O
varied	O
fonts	O
and	O
arbitrary	O
graphics	O
can	O
be	O
produced	O
.	O
</s>
<s>
Each	O
dot	O
is	O
produced	O
by	O
a	O
tiny	O
metal	O
rod	O
,	O
also	O
called	O
a	O
"	O
wire	O
"	O
or	O
"	O
pin	O
"	O
,	O
which	O
is	O
driven	O
forward	O
by	O
the	O
power	O
of	O
a	O
tiny	O
electromagnet	O
or	O
solenoid	B-Algorithm
,	O
either	O
directly	O
or	O
through	O
small	O
levers	O
(	O
pawls	O
)	O
.	O
</s>
<s>
The	O
plate	O
may	O
be	O
made	O
of	O
hard	O
plastic	O
or	O
an	O
artificial	O
jewel	O
such	O
as	O
sapphire	B-Application
or	O
ruby	B-Language
.	O
</s>
<s>
Actual	O
position	O
can	O
be	O
found	O
out	O
either	O
by	O
dead	O
count	O
using	O
a	O
stepper	B-Algorithm
motor	I-Algorithm
,	O
rotary	B-Algorithm
encoder	I-Algorithm
attached	O
to	O
one	O
wheel	O
or	O
a	O
transparent	O
plastic	O
band	O
with	O
markings	O
that	O
is	O
read	O
by	O
an	O
optical	O
sensor	O
on	O
the	O
printer	O
head	O
(	O
common	O
on	O
inkjets	O
)	O
.	O
</s>
<s>
Because	O
the	O
printing	O
involves	O
mechanical	O
pressure	O
,	O
dot	B-General_Concept
matrix	I-General_Concept
printers	O
can	O
create	O
carbon	O
copies	O
and	O
carbonless	O
copies	O
.	O
</s>
<s>
Although	O
nearly	O
all	O
inkjet	O
,	O
thermal	O
,	O
and	O
laser	O
printers	O
also	O
print	O
closely	O
spaced	O
dots	O
rather	O
than	O
continuous	O
lines	O
or	O
characters	O
,	O
it	O
is	O
not	O
customary	O
to	O
call	O
them	O
dot	B-General_Concept
matrix	I-General_Concept
printers	O
.	O
</s>
<s>
Dot	B-General_Concept
matrix	I-General_Concept
printers	O
have	O
one	O
of	O
the	O
lowest	O
printing	O
costs	O
per	O
page	O
.	O
</s>
<s>
Dot	B-General_Concept
matrix	I-General_Concept
printers	O
create	O
noise	O
when	O
the	O
pins	O
or	O
typeface	O
strike	O
the	O
ribbon	O
to	O
the	O
paper	O
,	O
and	O
sound-damping	O
enclosures	O
may	O
have	O
to	O
be	O
used	O
in	O
quiet	O
environments	O
.	O
</s>
<s>
The	O
common	O
serial	O
dot	B-General_Concept
matrix	I-General_Concept
printers	O
use	O
a	O
horizontally	O
moving	O
print	O
head	O
.	O
</s>
<s>
The	O
printing	O
speed	O
of	O
serial	O
dot	B-General_Concept
matrix	I-General_Concept
printers	O
with	O
moving	O
heads	O
varies	O
from	O
30	O
to	O
1550	O
characters	O
per	O
second	O
(	O
cps	O
)	O
.	O
</s>
<s>
In	O
a	O
considerably	O
different	O
configuration	O
,	O
so	O
called	O
line	O
dot	B-General_Concept
matrix	I-General_Concept
printers	O
use	O
a	O
fixed	O
print	O
head	O
almost	O
as	O
wide	O
as	O
the	O
paper	O
path	O
utilizing	O
a	O
horizontal	O
line	O
of	O
thousands	O
of	O
pins	O
for	O
printing	O
.	O
</s>
<s>
A	O
variation	O
on	O
the	O
dot	B-General_Concept
matrix	I-General_Concept
printer	O
was	O
the	O
cross	O
hammer	O
dot	O
printer	O
,	O
patented	O
by	O
Seikosha	O
in	O
1982	O
.	O
</s>
