The laser met specifications, but experiments are continuing to understand why
the plasma physics did not cooperate.
Industrial fiber lasers are now used
in some laser-weapon demonstrations.
Output from six indus-
trial fiber lasers feed into
a single beam director in
the Navy Laser Weapon
System (LaWS), de-
ployed on the USS Ponce
in the Persian Gulf in the
summer of 2014, where
it successfully detonated
targets (see Fig. 4).
Fiber lasers now lead
industrial laser sales, our
January 2015 market re-
view reported. Fibers ac-
count for $960 million
of the $2.62 billion in
2014 industrial laser
sales, ahead of carbon
dioxide with sales of
$874 million and bulk solid-state with
sales of $444 million (including both di-
ode and lamp-pumped). Back in 2004, fiber lasers were a distant fifth, accounting
for only $56 million of total $1.467 billion, with CO2 the leader at $597 million.
The future of solid-
Fiber lasers also hold the
record for output power, a 100 kW CW laser that IPG delivered
to Osaka University for
materials-working research. “In theory, if
you have enough money
you can get all the power you want from fiber
lasers,” says Bill Shiner,
now VP for industrial la-
sers at IPG. The 100 k W
beam comes from a 300
µm core, he says, so a 500 µm core might
generate a 200 k W beam.
Wall-plug efficiency continues to im-
prove. It has reached 45%, and in time
Shiner expects all fiber lasers to reach
that level. The combination of high power and efficiency will open new applications. “3D manufacturing in metals
would not happen without singlemode
fiber lasers,” he says (see Fig. 5).
“Fiber is phenomenal as a platform,”
says Bill Krupke, a former Livermore la-
ser researcher who consults on laser de-
velopment. Fiber lasers are so efficient
they can pump nonlinear optical sys-
tems or new solid-state infrared sources.
“People are starting to request kilowatt-
class green lasers,” he says. At wave-
lengths below 400 nm, he adds, “what’s
going to dominate going forward is the
emergence of new pump sources.”
Krupke also is fascinated by the po-
tential of nanolasers, which are still in
the early stages. He mentions “core-shell”
spherical devices in which an inner light
emitter excites a thin-film shell doped
with rare earths. Such devices might ac-
tivate individual neurons, or deliver light
precisely to cells for sensing applications.
More will doubtless follow and
bring us new generations of solid-state
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FIGURE 5. High-performance
bicycle hub components are
fabricated in batches in a powder-bed LAM process, as shown on
the February 2014 cover.