Development of fiber optic probes and a dual wavelength laser system for medical applications
Author
Uzcengiz Şimşek, Elif
Advisor
Ortaç, Bülend
Date
2016-01Publisher
Bilkent University
Language
English
Type
ThesisItem Usage Stats
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Abstract
Optical fibers have been widely used in the past several decades due to their
characteristics, such as laser energy transmission, low optical loss and different
beam shape. These features make them advantegous for different applications
in a number of fields such as telecommunication, imaging, laser cavity systems
and medical applications. Fiber optic probes were developed to use optical fiber
systems in medicine since they are
exible, small in diameter, easy to use and
they transmit the laser energy through the target tissue of the body without any
additional optical alignment. The tip geometry of the fiber optic probes can be
changed so that the laser radiation is emitted with different shapes. Flat-ended,
side-firing, radial, double radial and diffusing fiber optic probes, having different
beam shapes, were developed by using mechanical polishing and also, CO2 laser
polishing technique was demonstrated for fining radial fiber tips for the first time
throughout this study. The probes were analyzed in terms of ray tracing, Zemax
modelling, fabrication and light de
ection. As a result, the spatial distribution
of the fabricated probes were optimized. Different beam shapes originating from
each fiber optic probe can serve for specific purposes. One of them is to use the
diffusing probe as a cladding light stripper (CLS) in the fiber laser cavity since
it improves the beam quality of the fiber laser. On the other hand, endovenous
laser ablation (EVLA) is one of the operations that
at, radial and double radial
probes are preferred for ablating the varicose vein re
ux, which is a common
disease seen in 25% of women and 15% of men in the USA. A dual-wavelength
medical laser system (980nm-1470nm), operating both at continuous wave (cw)
and pulsed wave (pw), was also developed and characterized in terms of spectrum,
power and pulse duration. A whole medical laser system consisting of the
home-made radial fiber optic probe and the dual-wavelength medical laser system was assembled. In conclusion, design, development and characterization of the
fiber optic probes having different beam shapes were performed and two different
applications, namely CLS and a dual-wavelength medical laser system, were
presented.
Keywords
Fiber optic probesCladding light strippers
Dual wavelength medical laser system
Endovenous laser ablation (EVLA)