<s>
5D	B-Device
optical	I-Device
data	I-Device
storage	I-Device
(	O
also	O
branded	O
as	O
Superman	B-Device
memory	I-Device
crystal	I-Device
,	O
a	O
reference	O
to	O
the	O
Kryptonian	O
memory	O
crystals	O
from	O
the	O
Superman	B-Application
franchise	O
)	O
is	O
an	O
experimental	O
nanostructured	O
glass	O
for	O
permanently	O
recording	O
digital	O
data	O
using	O
a	O
femtosecond	O
laser	O
writing	O
process	O
.	O
</s>
<s>
Hitachi	O
and	O
Microsoft	O
have	O
researched	O
glass-based	O
optical	O
storage	O
techniques	O
,	O
the	O
latter	O
under	O
the	O
name	O
Project	B-Device
Silica	I-Device
.	O
</s>
