Download Implementing Multi-Touch screen for real

2. Theoretical background
and
bulky
technology
only
available
for
a
few.
The
real
breakthrough
that
made
the
technology
available
to
the
consumer
market
(large‐scale)
was
when
the
Iphone
was
released
in
2007.
This
changed
the
paradigm
on
how
a
user
interface
(UI)
should
be
designed
and
how
to
navigate
through
menus
etc.[5]
Most
people
are
probably
not
aware
of
the
fact
that
the
history
of
touch‐sensitive
control
actually
pre‐dates
the
age
of
the
PC
[6].
The
Iphone
that
some
might
think
of
as
the
first
real
Multi‐touch
device
was
actually
the
result
of
many
years
advancements
within
the
field
of
touch
devices
and
definitely
not
the
first
product
[1].
The
first
single‐touch
none
pressure
sensitive
screens
were
developed
as
early
as
the
late
1960's
and
by
1971
researchers
had
discovered
a
number
of
different
techniques
for
touch
screens.
Figure
1
shows
the
terminal,
a
16x16
array,
to
the
PLATO
IV
computer
assisted
education
system,
released
in
1972,
which
is
one
of
the
first
touch
systems
to
be
generally
known.
Similar
systems
like
the
PLATO
IV
are
infact
used
today
in
cashpoints,
ticketing
machines,
medical
instrumentation
etc.
[1]
Figure
1:
The
Plato
IV
terminal
with
its
touch‐sensitive
screen
[1].
The
University
of
Toronto's
Input
Reasearch
Group
developed
the
first
human‐input
Multi‐touch
technology
that
dates
back
to
1982
(Macintosh
released
its
first
computer
in
1984)
and
the
now
so
common
and
well
known
pinch
gesture
(see
table
1,
in
section
5.1.2,
for
description)
dates
back
to
1983
[6].
This
first
system
was
not
like
todays
Multi‐touch
screens
where
you
click
on
the
actual
object,
but
a
pad
with
a
frosted
glass
that
had
a
camera
behind
it.
The
camera
detected
the
fingers
pressed
on
the
screen
as
black
dots
on
an
otherwise
white
background
[6].
The
system
was
also
said
to
be
somewhat
pressure
sensitive
since
the
size
of
the
dot
depended
on
how
hard
the
person
was
pressing
on
the
glass.
The
system
was
used
for
simple
image
processing
like
drawing
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