<s>
A	O
hogel	B-Algorithm
(	O
a	O
portmanteau	O
of	O
the	O
words	O
holographic	B-Algorithm
and	O
element	O
)	O
is	O
a	O
part	O
of	O
a	O
light-field	O
hologram	B-Algorithm
,	O
in	O
particular	O
a	O
computer-generated	B-Algorithm
one	O
.	O
</s>
<s>
It	O
is	O
considered	O
a	O
small	O
holographic	B-Algorithm
optical	O
element	O
or	O
HOE	O
and	O
that	O
its	O
total	O
effect	O
to	O
that	O
of	O
a	O
standard	O
hologram	B-Algorithm
only	O
that	O
the	O
resolution	O
is	O
lower	O
and	O
it	O
involves	O
a	O
pixelated	O
structure	O
.	O
</s>
<s>
An	O
array	O
of	O
these	O
elements	O
form	O
the	O
complete	O
image	O
of	O
a	O
holographic	B-Algorithm
recording	O
,	O
which	O
is	O
typically	O
displayed	O
in	O
3D	O
free-viewing	O
device	O
.	O
</s>
<s>
In	O
contrast	O
to	O
2D	O
pixels	B-Algorithm
,	O
hogels	B-Algorithm
contain	O
the	O
direction	O
and	O
intensity	O
of	O
light	O
rays	O
from	O
many	O
perspectives	O
and	O
is	O
in	O
essence	O
what	O
is	O
referred	O
to	O
as	O
a	O
micro-image	O
in	O
plenoptic	O
imaging	O
terms	O
.	O
</s>
<s>
Synthetic	O
hogels	B-Algorithm
are	O
typically	O
rendered	O
through	O
double-frustum	O
,	O
oblique	O
slice	O
&	O
dice	O
or	O
polygonal/voxel	O
ray-tracing/ray	O
-casting	O
.	O
</s>
<s>
Research	O
into	O
efficient	O
generation	O
and	O
compression	O
of	O
hogels	B-Algorithm
may	O
allow	O
holographic	B-Algorithm
displays	O
to	O
become	O
more	O
widely	O
available	O
.	O
</s>
<s>
An	O
array	O
of	O
hogels	B-Algorithm
can	O
be	O
used	O
to	O
reconstruct	O
a	O
light-field	O
by	O
emitting	O
light	O
through	O
a	O
microlens	O
array	O
or	O
by	O
reflective/transmissive	O
photo-polymer	O
holograms	B-Algorithm
.	O
</s>
<s>
The	O
use	O
of	O
hogels	B-Algorithm
eliminates	O
the	O
limitation	O
on	O
the	O
number	O
and	O
size	O
of	O
pixels	B-Algorithm
as	O
well	O
as	O
the	O
size	O
of	O
the	O
lenses	O
that	O
constitute	O
the	O
lens	O
array	O
because	O
the	O
holograms	B-Algorithm
are	O
no	O
longer	O
physical	O
entities	O
.	O
</s>
<s>
Recorded	O
information	O
in	O
a	O
hogel	B-Algorithm
is	O
through	O
the	O
object	O
beam	O
.	O
</s>
<s>
The	O
term	O
"	O
hogel	B-Algorithm
"	O
was	O
coined	O
by	O
Mark	O
Lucente	O
who	O
first	O
used	O
it	O
in	O
his	O
1994	O
MIT	O
Doctoral	O
Thesis	O
Dissertation	O
.	O
</s>
<s>
More	O
recent	O
examples	O
include	O
a	O
paper	O
presented	O
at	O
the	O
SMPTE	O
2nd	O
Annual	O
International	O
Conference	O
on	O
Stereoscopic	B-Algorithm
3D	I-Algorithm
for	O
Media	O
and	O
Entertainment	O
entitled	O
"	O
The	O
First	O
20	O
Years	O
of	O
Holographic	B-Algorithm
Video	O
–	O
and	O
the	O
Next	O
20	O
"	O
,	O
or	O
in	O
these	O
recent	O
book	O
chapters	O
:	O
"	O
Electronic	O
Holography	B-Algorithm
--	O
20	O
Years	O
of	O
Interactive	O
Spatial	O
Imaging	O
"	O
in	O
Handbook	O
of	O
Visual	O
Display	O
Technology	O
,	O
and	O
"	O
Computational	O
Display	O
Holography	B-Algorithm
"	O
in	O
Holographic	B-Algorithm
Imaging	O
.	O
</s>
