<s>
Developed	O
by	O
Mitsubitshi	O
Electric	O
Research	O
Laboratories	O
,	O
a	O
privacy-enhanced	B-Device
computer	I-Device
display	I-Device
allows	O
information	O
that	O
must	O
remain	O
private	O
to	O
be	O
viewed	O
on	O
computer	B-Device
displays	I-Device
located	O
in	O
public	O
areas	O
(	O
i.e.	O
</s>
<s>
banks	O
,	O
hospitals	O
and	O
pharmacies	O
)	O
by	O
employing	O
the	O
use	O
of	O
both	O
ferroelectric	O
shutter	B-Algorithm
glasses	I-Algorithm
and	O
a	O
unique	O
device	B-Application
driver	I-Application
.	O
</s>
<s>
Prior	O
to	O
the	O
invention	O
of	O
privacy-enhanced	B-Device
computer	I-Device
display	I-Device
by	O
the	O
Mitsubitshi	O
Electric	O
Research	O
Laboratories	O
,	O
several	O
static	O
systems	O
that	O
serve	O
a	O
similar	O
purpose	O
were	O
established	O
.	O
</s>
<s>
Static	O
system	O
is	O
a	O
preventive	O
tool	O
that	O
protects	O
the	O
public	O
computer	B-Device
display	I-Device
without	O
any	O
dynamic	O
alterations	O
to	O
the	O
video	O
stream	O
itself	O
.	O
</s>
<s>
Such	O
polarizer	O
is	O
removed	O
when	O
the	O
computer	B-Device
display	I-Device
is	O
in	O
"	O
secure	O
use	O
"	O
.	O
</s>
<s>
Privacy-enhanced	B-Device
computer	I-Device
display	I-Device
technology	O
utilizes	O
a	O
public	O
display	O
image	O
(	O
denoted	O
Pij	O
for	O
the	O
pixel	O
value	O
at	O
location	O
i	O
,	O
j	O
in	O
the	O
public	O
image	O
)	O
,	O
a	O
secret	O
display	O
image	O
(	O
Sij	O
,	O
similarly	O
denoted	O
for	O
pixel	O
value	O
at	O
pixel	O
location	O
i	O
,	O
j	O
)	O
,	O
a	O
proprietary	O
device	B-Application
driver	I-Application
,	O
a	O
CRT	B-Device
capable	O
of	O
rapid	O
refresh	O
rates	O
(	O
up	O
to	O
120Hz	O
)	O
and	O
a	O
set	O
of	O
synchronized	O
ferroelectric	O
shutter	B-Algorithm
glasses	I-Algorithm
.	O
</s>
<s>
The	O
device	B-Application
driver	I-Application
causes	O
the	O
computer	B-Device
monitor	I-Device
to	O
alternately	O
display	O
the	O
pixelwise	O
difference	O
(	O
Pij	O
–	O
Sij	O
)	O
and	O
the	O
unaltered	O
secret	O
image	O
(	O
Sij	O
)	O
.	O
</s>
<s>
When	O
viewed	O
directly	O
without	O
the	O
shutter	B-Algorithm
glasses	I-Algorithm
,	O
the	O
human	O
eye	O
's	O
persistence	O
of	O
vision	O
blurs	O
the	O
two	O
images	O
into	O
[( 	O
Pij	O
–	O
Sij	O
+	O
Sij	O
)	O
/	O
2 ]	O
,	O
which	O
reduces	O
to	O
(	O
Pij	O
/	O
2	O
)	O
,	O
which	O
is	O
the	O
public	O
image	O
,	O
effectively	O
preventing	O
an	O
unintended	O
recipient	O
from	O
viewing	O
the	O
secret	O
image	O
.	O
</s>
<s>
Unfortunately	O
,	O
the	O
contrast	O
ratio	O
of	O
the	O
public	O
image	O
is	O
only	O
1/2	O
the	O
available	O
contrast	O
ratio	O
of	O
the	O
CRT	B-Device
when	O
driven	O
with	O
only	O
a	O
public	O
image	O
.	O
</s>
<s>
A	O
final	O
issue	O
is	O
the	O
decline	O
of	O
the	O
CRT	B-Device
and	O
the	O
rise	O
of	O
the	O
LCD	O
in	O
display	O
technology	O
,	O
because	O
nearly	O
all	O
LCDs	O
are	O
too	O
slow	O
to	O
support	O
the	O
120Hz	O
or	O
faster	O
refresh	O
rate	O
needed	O
for	O
this	O
privacy	O
enhancement	O
to	O
work	O
.	O
</s>
<s>
Meanwhile	O
,	O
lenticular	O
monitor	O
filters	O
have	O
diminished	O
the	O
need	O
for	O
the	O
shutterglass	B-Algorithm
technology	O
.	O
</s>
