Further information on the Ultrafast Optics Laboratory at www.sites.bu.edu/ufolab

1. Single mode: a single path of light
Cores are doped with rare earth ions such
as erbium or ytterbium [3]
Normal Population Inverted Population
Source: Laserfocusworld.com
Source: Ciscohite.wordpress.com
Source: orc.soton.ac.uk
Source: alphys.physics.ox.ac.ukk
Fiberoptic101.blogspot.com
Introduction
Objective: Build a fiber laser
With
the
advent
of
a
technologically
advanced
age
rose
the
fiber
op6c
world.
Fiber
op6cs
and
lasers
have
found
applica6ons
in
photonics,
where
lasers
have
recently
been
applied
in
photothermal
imaging.
These
imaging
systems
are
being
op6mized
through
the
use
of
fiber
lasers
as
opposed
to
conven6onal
lasers.
Fibers
lasers
are
preferable
due
to
their
high
efficiency
and
compact
design.
Generally
the
gain
fiber
is
spliced
using
specific
cleavers
and
then
fused
to
other
aspects
of
the
fiber
op6c
setup
to
create
oscilla6on
from
construc6ve
interference
in
a
resonance
cavity.
I
learned
how
to
strip,
cleave,
and
splice
these
fibers,
and
to
how
to
plot
and
analyze
data.
I
became
familiar
with
Matlab,
eventually
wri6ng
a
program
that
ploCed
and
analyzed
the
laser’s
op6cal
spectrum,
characterizing
the
laser’s
central
wavelength
and
bandwidth.
I
then
used
wavelength
division-­‐mul6plexing
to
build
a
laser.
I
measured
the
output
power
and
ploCed
the
op6cal
spectrum
through
Matlab.
Abstract
Characterization and Construction of a Fiber Optic Laser
Janani Chinnam [1,2], Hui Liu [2], Michelle Sander [2]
Stoney Creek High School, 575 E. Tienken Rd., Rochester Hills, MI 48306 [1]; Department of Electrical and Computer
Engineering, The Boston University Photonics Center, 8 Saint Mary’s St., Boston, MA 02215 [2]
Methods / Materials
Results
Conclusion
References
Acknowledgments
Fiber
probe
lasers
have
many
applica6ons,
one
of
which
is
integra6on
into
photothermal
microspectroscopy
setups
for
chemical
and
biological
samples.
[4]
Set-up:
1
2
3
4
Strip outer
cladding off
fibers
Clean and
cleave fibers
Splice fibers
with minimal
losses
Splice APC to
FBG, PC to gain,
and gain to FBG
(Fiber Bragg
Grating)
If necessary,
examine fibers
with microscope
and clean/polish
[3] Hecht, Jeff. Understanding Lasers: An Entry-level Guide.
New York: IEEE, 1994. Print.
[4] M. Y. Sander, "Compact Femtosecond Lasers and
Applications in Photothermal Spectroscopy," in Imaging and
Applied Optics 2014, OSA Technical Digest (online) (Optical
Society of America, 2014), paper LM4D.1.
Special thanks to,
The Boston University Research Internship in Science and
Engineering Summer Term Program
The Ultrafast Optics Laboratory located in the Boston
University Photonics Center
Michelle Sander, Hui Liu, Atcha Totachawattana, James
Bezuk, and Ahmet Akosman for their guidance.
FBG
Output
Coupler
Output 1
Erbium Fiber (Gain)
Wavelength
Division
Multiplexer
977 nm
SMF
Laser Cavity
Output 2
Splicing Losses
APC to FBG: 0.09 dB
PC to Gain: 0.09 dB
Gain to FBG: 0.28 dB
FBG Bandwidth: 0.348 nm
Center Wavelength: 1560.168 nm
Current While Lasing; 200 milliamps
Advantages
of
a
fiber
laser
as
opposed
to
a
tradi6onal
laser:
• Compact
• Highly
efficient
• Easy
to
transport
• Adaptable
• High
photon
conversion
efficiency
• Easy
to
integrate
• Light
weight
• Flexible
• Rugged
• Small
• Inexpensive
Optical
Spectrum
before lasing
begins
Optical
Spectrum
during lasing
[4]
[4]
Source: Americomtech.com
Abblg.com Thorlabs.com