<s>
The	O
paper	B-Device
disc	I-Device
is	O
a	O
digital	O
disc	O
format	O
.	O
</s>
<s>
The	O
basic	O
structure	O
of	O
Sony	O
's	O
paper	B-Device
disc	I-Device
is	O
similar	O
to	O
that	O
of	O
a	O
Blu-ray	O
Disc	O
in	O
that	O
the	O
recording	O
layer	O
on	O
which	O
the	O
data	O
is	O
stored	O
lies	O
under	O
a	O
0.1	O
millimeter	O
protective	O
layer	O
and	O
on	O
top	O
of	O
a	O
1.1	O
millimeter	O
substrate	O
.	O
</s>
<s>
In	O
a	O
Blu-ray	O
Disc	O
,	O
this	O
substrate	O
is	O
made	O
of	O
polycarbonate	O
plastic	O
,	O
which	O
is	O
replaced	O
with	O
paper	O
in	O
a	O
paper	B-Device
disc	I-Device
.	O
</s>
