Abstract: A method wherein the levels of a plurality of points on the surface of a moving rolled strip are determined in relation to a horizontal reference plane by optical triangulation and planarity, or flatness, indices of the strip are deduced therefrom. The position of at least one of the side edges of the strip is detected with respect to a predetermined fixed reference in a cross-section of the strip containing at least plurality of points. The real, or true, position of the point with respect to the fixed reference is deduced and the orientation of the emitted beam and of the re-transmitted, or reflected, beam used in the triangulation is modified to compensate for the real, or true, position of the point.

Abstract: The surface and/or subsurface defects of the surface to be treated are detected, preferably over the entire said surface. The defects are eliminated by scarfing with a torch and/or by milling, following which the treated surface is inspected and cleaned. The detection, elimination, inspection, and cleaning devices are maneuvered by means of programmable robots or automatons controlled by a computer. The process may be applied on-line to hot, moving products (e.g., rolled or continuous cast products).

Abstract: Optical beams from lasers are directed towards the middle and edges of a hot rolled steel sheet by fixed mirrors and rotatable mirrors which allow for different sheet widths. The points of incidence of the beams are observed by photodiode cameras whose receiving axes are orientated by fixed mirrors and rotatable mirrors so that the points remain in the respective fields of observation of the cameras. The levels of the points are obtained by triangulation and are used in the calculation of the planarity of the sheet.

Abstract: A telemetric optical-radiation laser transmitter 5 outside an aperture 2 sends a beam to a point 14 scanned over the charge surface 1, via a rotating assembly 7 of deflectors, one deflector 11 oscillating with a periodicity related to the rotation of the assembly. A telemetric receiver 19, sensitive to the radiation from the transmitter 5 in a selected wavelength range, receives radiation re-transmitted from the point 14 through an aperture 3. A thermometric receiver 6 receives thermal radiation from the point 14 along a path coinciding with the path of the transmitted optical radiation.

Abstract: An assembly of light path deflectors is arranged so that radiation is transmitted along a folded optical path to an observation or measuring instrument (e.g. a pyrometer) from a point on a surface in an enclosure such as a blast furnace. The point is scanned along a scanning path (preferably spiral) which is uniformly distributed about the intersection of the surface with the sighting axis of the instrument, by simultaneously rotating the assembly and rotating at least one of the deflectors.

Abstract: To determine a dimension of an article, a beam is directed at the article by means of a first mobile deflector so as to scan the part of the profile of the article comprising the dimension to be measured. Rays reflected by the article are orientated in the direction of at least one receiver by means of a second mobile deflector. The deflectors are angularly moved at different speeds. The positions occupied by two points related with the dimension are determined. The dimension is calculated with respect to these points.

Abstract: To determine a dimension of an object, two emitted beams whose axes define a known angle are directed by means of a deflector onto points of the object related to the dimension to be determined so that when one beam falls on the first of two points defining the dimension the other beam falls on the second point. Light rays reflected by the two points are received as two beams by means of a receiver. The angle of incidence of the emitted beam is measured with respect to a direction. The angles made respectively by the axes of the two received beams with the axes of the emitted beams are measured. The dimension is calculated from the angles.

Abstract: The profile of a surface of an object is determined by scanning the line of intersection of this surface and a given plane transverse to the object. A radiation transmitter provides a transmitting beam, and a radiation receiver provides a receiving beam. Deflection means causes scanning movement of one or both of the beams so that a zone of intersection of the beams scans along a predetermined line and a detector in the receiver receives radiation transmitted from a source in the transmitter and reflected by the surface of the object. The deviation of the actual line of intersection from the predetermined line is determined from data supplied by the detector at a plurality of positions along the line of intersection.