<s>
The	O
double-density	B-Device
compact	I-Device
disc	I-Device
(	O
DDCD	B-Device
)	O
is	O
an	O
optical	B-Device
disc	I-Device
technology	O
developed	O
by	O
Sony	O
using	O
the	O
same	O
laser	O
wavelength	O
as	O
a	O
compact	O
disc	O
,	O
namely	O
780	O
nm	O
.	O
</s>
<s>
The	O
format	O
is	O
defined	O
by	O
the	O
Purple	B-Device
Book	I-Device
standard	O
document	O
.	O
</s>
<s>
Unlike	O
the	O
compact-disc	O
technology	O
it	O
is	O
based	O
on	O
,	O
DDCD	B-Device
was	O
designed	O
exclusively	O
for	O
data	O
,	O
with	O
no	O
audio	O
capabilities	O
.	O
</s>
<s>
For	O
a	O
12	O
cm	O
disc	O
,	O
it	O
doubles	O
the	O
original	O
650	O
MB	O
to	O
1.3	O
GB	O
capacity	O
of	O
a	O
CD	O
on	O
recordable	O
(	O
DDCD-R	O
)	O
and	O
rewritable	O
(	O
DDCD-RW	B-Device
)	O
discs	O
by	O
narrowing	O
the	O
track	O
pitch	O
from	O
1.6	O
to	O
1.1	O
micrometers	O
,	O
and	O
shortening	O
the	O
minimum	O
pit	O
length	O
from	O
0.833	O
to	O
0.623	O
micrometers	O
.	O
</s>
<s>
The	O
DDCD	B-Device
was	O
also	O
available	O
in	O
read-only	O
format	O
(	O
DDCD-ROM	O
)	O
.	O
</s>
<s>
The	O
only	O
DDCD	B-Device
recorder	O
introduced	O
was	O
the	O
Sony	O
CRX200E	O
.	O
</s>
<s>
A	O
similar	O
technology	O
,	O
however	O
,	O
was	O
used	O
in	O
the	O
GD-ROM	B-Device
discs	O
primarily	O
used	O
for	O
Sega	B-Operating_System
Dreamcast	I-Operating_System
software	O
.	O
</s>
<s>
DVD	O
offered	O
a	O
significantly	O
higher	O
capacity	O
-	O
nearly	O
four	O
times	O
more	O
than	O
DDCD-R	O
with	O
4.7	O
GB	O
on	O
single	O
layer	O
discs	O
and	O
six	O
and	O
a	O
half	O
times	O
more	O
with	O
8.5	O
GB	O
on	O
double	O
layer	O
discs	O
and	O
would	O
drop	O
significantly	O
in	O
cost	O
in	O
the	O
years	O
after	O
DDCD	B-Device
's	O
launch	O
.	O
</s>
<s>
The	O
DDCD	B-Device
technology	O
was	O
marked	O
as	O
'	O
legacy	O
 '	O
in	O
the	O
2006-edition	O
of	O
the	O
SCSI	O
Multimedia	O
Commands	O
set	O
(	O
MMC	O
)	O
.	O
</s>
<s>
DDCD	B-Device
was	O
part	O
of	O
a	O
wave	O
of	O
technologies	O
aimed	O
at	O
enhancing	O
the	O
compact	O
disc	O
,	O
none	O
of	O
which	O
managed	O
to	O
gain	O
much	O
market	O
share	O
.	O
</s>
<s>
MultiLevel	B-Device
Recording	I-Device
(	O
ML	O
)	O
,	O
developed	O
in	O
1992	O
by	O
Optex	O
Corporation	O
,	O
was	O
a	O
proposed	O
technology	O
that	O
never	O
saw	O
the	O
light	O
of	O
the	O
day	O
.	O
</s>
<s>
In	O
September	O
2002	O
,	O
Sanyo	O
announced	O
it	O
had	O
achieved	O
the	O
same	O
result	O
as	O
DDCD	B-Device
using	O
standard	O
CD-Rs	O
with	O
its	O
HD-Burn	O
technology	O
.	O
</s>
<s>
Like	O
DDCD	B-Device
,	O
the	O
result	O
was	O
achieved	O
by	O
burning	O
smaller	O
pits	O
.	O
</s>
