sborník

Gunter Weiss
In the following some own experiences shall be represented by two
diploma theses: The first one of F. HENSCHEL deals with Computer Vision
and Linear Mappings. In cooperation with a software firm the theme was to
reconstruct an object from planar freehand sketches, see figure 3 and 4. The
professional software already had some modules for central projection, and
they had to be used also in the thesis, in spite of sketches not being exact
central projections and in spite of the principle point not being the centre of
the box, in which the object is embedded. So even one could easily improve
the algorithms by applying some geometrical knowledge, the firm rather
wants to implement an approximation algorithm than to accept the better
solution.
Figure 4: Inexact reference points
The second diploma thesis deals with material science and elementary
geometry. A rotating crystalline probe reflects a laser beam onto a screen.
Reflection happens, when the ray forms a special angle with the grid planes
of the crystal. The traces of the reflected rays on the screen are conic
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