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Abstract: |
Infrared-transmissive hollow waveguides (HWGs)
are enjoying a resurgence resulting from emerging applications
in a variety of sensor and power delivery systems. These HWGs
consist of glass or polymer tubes with highly reflective
metallic and dielectric coatings deposited on the inside
surface. They are normally fabricated for transmission from
transmit from 2 to 12 µm but they have also been made for the
transmission of visible and THz radiation. Losses in the IR
regime are less than 1 dB/m and lengths as long as 10 m have
been made. The most successful structure has been the Ag/AgI
coated hollow silica waveguides which are now being used to
transmit broadband spectral information for thermal imaging and
spectroscopy as well as for IR laser surgery. A brief history of
the development of these unique structures will be given
followed by a more detailed description of the optical
properties of the HWGs. A variety of applications will be
described including those involving laser power delivery in
surgery, thermal imaging, and spectroscopy.
In
addition to the technical presentation on hollow waveguides, I
will also briefly describe my year working as a scientist at the
Department of State. While there is generally a paucity of
scientists at State, I found that scientists can play a key role
assisting our foreign policy makers on science related issues.
My year at State was spent as the science advisor for the
control of dual-use, high technology items which the US controls
either though the Department of Commerce or Defense (ITAR). I
will review my year at State including examples of what types of
technologies are controlled along with my work on visa related
issues. During my year I have seen first hand the importance of
science in the development of a sound foreign policy. Clearly
there is an important role for a scientist at State yet I have
learned that even though the science may be straightforward the
path to achieving the final export controls is often filled with
diplomatic potholes.
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Bio: |
Dr.
Harrington has over thirty-five years of research experience in
the area of optical properties of solids. Since 1977 he has
worked on all aspects of infrared fibers including fabrication,
characterization, and applications. He is generally recognized
as one of the world's leading experts in this continually
evolving field. His current research interests include the
development of fiber optics for use in the delivery of laser
power in surgical and industrial applications and for use as
chemical and thermal fiber sensors. Specifically, these new
fibers include hollow glass waveguides and solid core,
single-crystal sapphire fibers for the delivery of CO2,
Er:YAG, and FEL
laser radiation and for spectroscopic and thermometric
applications aimed at the identification of chemical species and
the measurement of low and high (>1500 C) temperature
radiation. He is the inventor of hollow glass waveguides, which
today are being used as CO2 laser delivery systems in
gynecology, arthroscopy, and dentistry. His book, Infrared
Fibers and Their Applications, SPIE Press, January, 2004
provides a comprehensive overview of IR fiber optics and an
entry point for those wishing to learn more about this growing
field.
Dr.
Harrington has spent many years in service to the optical
community primarily through his professional association with
SPIE, The International Society for Optical Engineering and
through his work as a science advisor to the US Department of
State. As member of SPIE’s leadership and in 2002 as President
of SPIE he traveled extensively promoting optics research and
education. He has met with many leaders in the US, Europe, and
the far East to help arrange professional society meetings that
promote not only many technical areas involving the broad field
of optics but also to encourage many students to participate in
professional conferences. Through his chairmanship of the US
Advisory Committee of the International Commission on Optics (USAC/ICO),
he has been very involved in working with a team of dedicated
optics professionals to promote optics and photonics on a
national level. During the 2005-2006, Dr. Harrington was a
Jefferson Science Fellow at the US Department of State. He
worked as a science advisor within the Bureau of International
Security and Nonproliferation, Office of Conventional Arms and
Threat Reduction (ISN/SATR) where he assisted in the
establishment of controls for dual-use high technology goods.
Specifically, his work with State, the Departments of Defense,
Commerce, and the 40 nations making up the Wassenaar Arrangement
helped establish controls for lasers and for low-light level
sensors and cameras. His interests include control of dual-use
technology, non-immigrant visas, and the application of non-life
science and engineering solutions to improve the standard of
living in less developed countries.
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