Manuel Francisco da Costa Vitor - Estudo Geral - Universidade de ...

Abstract
The central aspect of the present work in this dissertation consists of an
upgrade to the ocular fluorometer PAF (Photodiode Array Fluorometer). The
structure of its development is based on three main under divisions.
At first it is presented the technique, ocular fluorometry, its clinical
purpose and the goals of the work (Chap. 1).
On a second approach – of denser content - the technical aspects of the
optimized device, the PAF, are explained with some detail. Special attention is
drawn on the process of evolution of the system in relation to its first version,
description of the data acquisition system with its main components – hardware,
the three image sensors used (NMOS SSPDA 128 pixels and 256 pixels; FFT-
CCD detector) and the optical system with the improvements related. Software,
as part of the system PAF, is still described in this phase of the work. Using
MATLAB, the existent graphical user interface was improved and new menus
were created, to support the sensors calibration and for statistical treatment of
data acquired by the system. Operational simplicity and economy of time in the
calibration process were the great profits. The MPLAB was the program chosen
to do the improvements in the microcontroller project, in order to make it
compatible with all sensors used (referring to CCD, the source code was made
from zero). OSLO was the tool chosen to simulate the PAF lens system that
served as support to the implementation of a deviator (an aluminium structure)
for correction of the angular position of the sensors (Chap. 2).
The third main point of this study is the discussion on the results,
specifically: linearity, reproducibility and low level of detection tests for the
SSPDA sensors; the practical study of the angular position using the angular
deviator; tests in patients (Chap. 3).
The conclusion and future work are the last two chapters and they reflect,
respectively, the measure of achievement of the goals proposed and the
projection of the possible evolutions of the PAF fluorometer in order to a future
real clinical application, with high degree of portability and reliability (Chap. 4
and Chap. 5).
Keywords: Ocular Fluorometry; PAF.
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