The object of this work (featuring the study of alignment of lines in
space) is to produce a novel system for automatic production of
optoelectronic components. It begins by reviewing the different
components associated with optical fibre transmission and examines
the existing laser-fibre coupling methods. The manual alignment
technique adopted by STC to align a laser beam with a monomode
optical fibre is then presented.
The various interpretations of alignment are explored. The results
obtained from the analysis determine the type of manipulator required
for laser to optical fibre coupling. The central axis of a divergent
beam emitted by a semi-conductor laser diode is manipulated for
alignment with the axis of the fibre. Such an alignment places
stringent displacement tolerance and accuracy demands on the
To construct a manipulator, actuators need to be coupled together.
The coWling methods are studied and presented. Prior to this study,
commercially available actuators are surveyed leading to the
selecticin of the Oriel Encoder Mike actuator. This actuator exhibits
some inherent control problems but meets the laser-fibre coupling
accuracy demands. Various types of couplings are also examined based
on the expansion of the Kelvin coupling for the construction of a
four degree of freedom manipulator. A computational algorithm
analogous to that used to solve two plane balancing problems is
sucessfully tested on this manipulator for alignment of a
conventional He-Ne laser beam with the centres of two transparent
screens. This algorithm requires linearity for its success. For this
reason and for purposes of completeness, spatial displacement
characteristics of the manipulator are analysed and confirmed
This work ends with the ocnstruction. and testing of a program based
on a hill climbing technique for the control of a three degree of
freedom (Oriel Encoder Mike) manipulator to align a laser beam
emitted by a semi-conductor laser diode with a monomode optical fibre.
A Doctoral Thesis. Submitted in partial fulfillment of the requirements for the award of Doctor of Philosophy of Loughborough University.