Abstract

This study evaluated the capability of conoscopic holography (CH) to digitise and geometrically analyse PLA surfaces of different colours and thicknesses, manufactured using FFF.

The results show a clear influence of the material colour on the quality of the digitisation. The blue specimens provided the best results, allowing all points to be captured and yielding height measurements very close to the nominal values, regardless of the number of layers. The red and white specimens exhibited lower signal quality, although they allowed the surfaces to be reconstructed with a high proportion of captured points and produced dimensional results similar to those obtained for the blue specimens.

In contrast, the black specimens produced the poorest results, due to the low proportion of captured points and the larger discrepancies in the measurements obtained.

Overall, it can be concluded that CH technology is suitable for the digitisation and geometric analysis of PLA parts manufactured using FFF, provided that the material has sufficient reflectivity and does not excessively absorb the laser light. These results provide a basis for future studies aimed at extending the application of this technology to other materials, colours and geometries.