Abstract: In the field of determining the three-dimensional profile of a surface, a system and a method for determining such a three-dimensional profile use a plenoptic camera and a structured lighting system. The method includes: acquiring a sequence of plenoptic images, each formed by a set of pixels each associated with a light intensity of an imaged surface element, and including a plurality of sub-images of the surface from different viewing angles, projecting onto the surface a sequence of structured images synchronised with the sequence of plenoptic images illuminating each imaged surface element by a succession of light intensities different from the successions of light intensities which illuminate the other imaged surface elements, constructing, for each pixel of the plenoptic image, an intensity vector representing the succession of light intensities, and pairing each pixel of a sub-image with a pixel of another sub-image depending on a similarity of the intensity vectors.

Abstract: A method for inspecting the surface finish of a cast part made of single-crystal metal, the surface of the part potentially containing defects resulting from an inhomogeneity of orientation of at least a crystal lattice of the single-crystal metal, the method including acquiring, using an image-acquiring device, a series of images of the cast part illuminated by a polarized and collimated illuminating device, then analysing the series of images by an image-processing device, each image of the series of images being taken at a different polarization angle.

Abstract: In the field of determining the three-dimensional profile of a surface, a system and a method for determining such a three-dimensional profile use a plenoptic camera and a structured lighting system. The method includes: acquiring a sequence of plenoptic images, each formed by a set of pixels each associated with a light intensity of an imaged surface element, and including a plurality of sub-images of the surface from different viewing angles, projecting onto the surface a sequence of structured images synchronised with the sequence of plenoptic images illumating each imaged surface element by a succession of light intensities different from the successions of light intensities which illuminate the other imaged surface elements, constructing, for each pixel of the plenoptic image, an intensity vector representing the succession of light intensities, and pairing each pixel of a sub-image with a pixel of another sub-image depending on a similarity of the intensity vectors.

Abstract: Articles of jewelry with gems set in precious metal are cast by a modified lost wax method whereby each gem is retained in position in the investment mold after removal of the wax enabling the setting of the gem to be simultaneous with the casting of the precious metal. The wax model of the article of jewelry is molded with undercut grooves in the sidewall of the gem seat located to engage portions of the girdle of the gem for retention thereof in set position in the finished article. The wax for the model is formulated to provide resiliency to permit the gem to be snapped into position in the wax model prior to embedding the model with the gem set therein in investment material in the conventional flask. Curing time is reduced to approximately one half the conventional fourteen hours by precise control of predetermined time and temperature which also prevents marring of the gems during the curing of the investment and the casting of the precious metal.