<s>
Three-dimensional	B-Algorithm
face	I-Algorithm
recognition	I-Algorithm
(	O
3D	B-Algorithm
face	I-Algorithm
recognition	I-Algorithm
)	O
is	O
a	O
modality	O
of	O
facial	O
recognition	O
methods	O
in	O
which	O
the	O
three-dimensional	O
geometry	O
of	O
the	O
human	O
face	O
is	O
used	O
.	O
</s>
<s>
It	O
has	O
been	O
shown	O
that	O
3D	B-Algorithm
face	I-Algorithm
recognition	I-Algorithm
methods	O
can	O
achieve	O
significantly	O
higher	O
accuracy	O
than	O
their	O
2D	O
counterparts	O
,	O
rivaling	O
fingerprint	O
recognition	O
.	O
</s>
<s>
3D	B-Algorithm
face	I-Algorithm
recognition	I-Algorithm
has	O
the	O
potential	O
to	O
achieve	O
better	O
accuracy	O
than	O
its	O
2D	O
counterpart	O
by	O
measuring	O
geometry	O
of	O
rigid	O
features	O
on	O
the	O
face	O
.	O
</s>
<s>
Additionally	O
,	O
most	O
3D	B-Algorithm
scanners	I-Algorithm
acquire	O
both	O
a	O
3D	O
mesh	O
and	O
the	O
corresponding	O
texture	O
.	O
</s>
<s>
The	O
main	O
technological	O
limitation	O
of	O
3D	B-Algorithm
face	I-Algorithm
recognition	I-Algorithm
methods	O
is	O
the	O
acquisition	O
of	O
3D	O
image	O
,	O
which	O
usually	O
requires	O
a	O
range	B-Algorithm
camera	I-Algorithm
.	O
</s>
<s>
(	O
See	O
3D	B-Algorithm
data	I-Algorithm
acquisition	I-Algorithm
and	I-Algorithm
object	I-Algorithm
reconstruction	I-Algorithm
.	O
)	O
</s>
<s>
This	O
is	O
also	O
a	O
reason	O
why	O
3D	B-Algorithm
face	I-Algorithm
recognition	I-Algorithm
methods	O
have	O
emerged	O
significantly	O
later	O
(	O
in	O
the	O
late	O
1980s	O
)	O
than	O
2D	O
methods	O
.	O
</s>
<s>
3D	B-Algorithm
face	I-Algorithm
recognition	I-Algorithm
is	O
still	O
an	O
active	O
research	O
field	O
,	O
though	O
several	O
vendors	O
offer	O
commercial	O
solutions	O
.	O
</s>
