<s>
A	O
hypercentric	B-General_Concept
or	O
pericentric	B-General_Concept
lens	I-General_Concept
is	O
a	O
lens	O
system	O
where	O
the	O
entrance	O
pupil	O
is	O
located	O
in	O
front	O
of	O
the	O
lens	O
,	O
in	O
the	O
space	O
where	O
an	O
object	O
could	O
be	O
located	O
.	O
</s>
<s>
The	O
geometry	O
of	O
a	O
hypercentric	B-General_Concept
lens	I-General_Concept
can	O
be	O
visualized	O
by	O
imagining	O
a	O
point	O
source	O
of	O
light	O
at	O
the	O
center	O
of	O
the	O
entrance	O
pupil	O
sending	O
rays	O
in	O
all	O
directions	O
.	O
</s>
<s>
This	O
inversion	O
of	O
normal	O
perspectivity	B-Application
can	O
be	O
useful	O
for	O
machine	B-General_Concept
vision	I-General_Concept
.	O
</s>
<s>
Imagine	O
a	O
six-sided	O
die	B-Language
sitting	O
on	O
a	O
conveyor	O
belt	O
being	O
imaged	O
by	O
a	O
hypercentric	B-General_Concept
lens	I-General_Concept
system	O
directly	O
above	O
,	O
whose	O
entrance	O
pupil	O
is	O
below	O
the	O
conveyor	O
belt	O
.	O
</s>
<s>
The	O
image	O
of	O
the	O
die	B-Language
would	O
contain	O
the	O
top	O
and	O
all	O
four	O
sides	O
at	O
once	O
,	O
because	O
the	O
bottom	O
of	O
the	O
die	B-Language
appears	O
larger	O
than	O
the	O
top	O
.	O
</s>
