Abstract: This installation includes a support for the object, a panel having a fringe pattern alternating pale and dark lines, the pattern having a first series of parallel fringes extending in a first direction and at a first pitch, and a second series of parallel fringes extending in a second direction perpendicular to the first direction and at a second pitch, illuminating means arranged to illuminate the fringe pattern, at least one imaging capturing means to capture an image of the pattern reflected or transmitted by the surface of the object, and where at least one of the support, the panel and the capturing means is mobile between a plurality of positions, the movement between two successive positions of each chosen element being designed so as to produce a predetermined phase shift between two images of the pattern reflected or transmitted by said surface.

Abstract: This device for inspecting surfaces by deflectometry comprises: a display device (2) designed to generate, on its face called the front face, a pattern of alternate light and dark fringes; at least one sensor (3) designed to acquire the image reflected by the surface to be inspected (5) positioned on the front face of the display device and at the periphery of the latter; and a reflecting means positioned in relation to the surface to be inspected (5) so as to direct the image reflected by the surface to be inspected (5) toward the sensor (3), the display device being oriented in relation to the surface to be inspected at an angle such that the display device is viewed by the sensor at normal incidence.

Abstract: A process for scanning a surface of a substrate, which process takes at least one reflected image of at least one test pattern on the surface and extracts by digital processing local phases in two directions. Variations in local slopes are calculated by digital processing from the local phases to deduce therefrom variations in curvature or variations in altitude of the surface.

Abstract: The object of the invention is a process for scanning a surface of a substrate (2), which process consists in taking at least one reflected image of at least one test pattern (1) on the said surface and extracting by digital processing local phases in two directions, characterized in that variations in local slopes are calculated by digital processing from the local phases in order to deduce therefrom variations in curvature or variations in altitude of the said surface.

Abstract: A system for measuring optical wavelengths of the kind sometimes referred to as a lambdameter. The invention applies to systems based on equipment of the interferometer type having an offset in time (FIG. 1) or in space (FIG. 4) enabling a reference optical wavelength to be compared with unknown optical wavelengths to be determined without any mechanical displacement of optical parts being needed during measurement. Original methods of calculation of the algorithmic type adapted to detecting phase associated with the least squares method are used for processing information. The measurement uncertainty of such a novel lambdameter is very small.