<s>
A	O
fiber	B-Device
disk	I-Device
laser	I-Device
is	O
a	O
fiber	B-Device
laser	I-Device
with	O
transverse	O
delivery	O
of	O
the	O
pump	O
light	O
.	O
</s>
<s>
They	O
are	O
characterized	O
by	O
the	O
pump	O
beam	O
not	O
being	O
parallel	O
to	O
the	O
active	O
core	O
of	O
the	O
optical	B-Architecture
fiber	I-Architecture
(	O
as	O
in	O
a	O
double-clad	B-Device
fiber	I-Device
)	O
,	O
but	O
directed	O
to	O
the	O
coil	O
of	O
the	O
fiber	O
at	O
an	O
angle	O
(	O
usually	O
,	O
between	O
10	O
and	O
40	O
degrees	O
)	O
.	O
</s>
<s>
Fiber	B-Device
disk	I-Device
lasers	I-Device
should	O
not	O
be	O
confused	O
with	O
the	O
LaserDiscs	O
(	O
disk-shaped	O
devices	O
for	O
storage	O
and	O
reading	O
of	O
information	O
with	O
laser	O
beam	O
)	O
nor	O
the	O
disk	O
laser	O
or	O
"	O
active	O
mirror	O
"	O
,	O
which	O
is	O
a	O
laser	O
with	O
a	O
thin	O
active	O
layer	O
where	O
the	O
heat	O
sink	O
is	O
realized	O
in	O
a	O
direction	O
opposite	O
to	O
that	O
of	O
propagation	O
of	O
the	O
output	O
beam	O
.	O
</s>
<s>
Several	O
realizations	O
of	O
fiber	B-Device
disk	I-Device
lasers	I-Device
were	O
reported	O
.	O
</s>
<s>
The	O
fiber	B-Device
disk	I-Device
laser	I-Device
is	O
so	O
named	O
because	O
the	O
fiber	O
is	O
tightly	O
coiled	O
.	O
</s>
<s>
Fiber	B-Device
disk	I-Device
lasers	I-Device
are	O
used	O
for	O
cutting	O
of	O
metal	O
(	O
up	O
to	O
few	O
mm	O
thick	O
)	O
,	O
welding	O
and	O
folding	O
.	O
</s>
<s>
When	O
the	O
increase	O
of	O
the	O
length	O
of	O
the	O
fiber	O
becomes	O
limited	O
by	O
stimulated	O
scattering	O
,	O
additional	O
power	O
scaling	O
can	O
be	O
achieved	O
by	O
combining	O
several	O
fiber	B-Device
disk	I-Device
lasers	I-Device
into	O
a	O
stack	O
.	O
</s>
<s>
The	O
spiral-coiled	O
configuration	O
is	O
not	O
the	O
only	O
possible	O
arrangement	O
;	O
any	O
other	O
scheme	O
of	O
stacking	O
of	O
optical	B-Architecture
fibers	I-Architecture
with	O
lateral	O
delivery	O
of	O
pump	O
can	O
also	O
be	O
called	O
a	O
fiber	B-Device
disk	I-Device
laser	I-Device
,	O
even	O
if	O
the	O
resulting	O
shape	O
of	O
the	O
device	O
is	O
not	O
circular	O
.	O
</s>
<s>
The	O
term	O
fiber	B-Device
disk	I-Device
laser	I-Device
applies	O
to	O
the	O
concept	O
of	O
lateral	O
delivery	O
of	O
pump	O
to	O
the	O
active	O
optical	B-Architecture
fiber	I-Architecture
rather	O
than	O
specifically	O
to	O
a	O
disk-shaped	O
device	O
.	O
</s>
<s>
The	O
optimal	O
shape	O
of	O
the	O
fiber	B-Device
disk	I-Device
laser	I-Device
may	O
depend	O
on	O
the	O
properties	O
of	O
the	O
beam	O
of	O
pump	O
available	O
,	O
as	O
well	O
as	O
on	O
the	O
specific	O
application	O
.	O
</s>
