Abstract: The invention relates to a periscope installation sighting head, particuly for a submarine, located at the upper end of a periscope mast and including at least one optical sighting unit off-set laterally with respect to the axis of the mast. To stabilize, in azimuth and in elevation, the image provided by the sighting unit when the mast is animated by a swinging movement, the sighting unit is positioned on a mobile support with two gyrostabilized axles and a trajectory correction device as a parallel-sided plate is interposed in the path of the signals delivered by said unit and is slaved to the azimuth of the unit so that the signals are transmitted to the mast substantially along the optical axis of the latter.

Abstract: A periscopic installation with multi sighting heads for submarines comprig: two mobile masts (1,2) carrying sighting heads (3;4) and permanently situated outside the hull (7) of the submarine whatever their position (raised or lowered); a sealing protecting structure (8) surrounding the masts; two through means (11,12) passing sealingly through the hull (7) and adapted to provide through the hull, transmission of the signals supplied by the sighting heads; two means (13,14) for receiving said signals situated inside the hull and connected respectively to the through means; a single observation post (10) situated inside the hull for observing the signals at (18); and switching means (16) inserted between the observation post and the receiving means and adapted to selectively connect the observation post with one of the receiving means.

Abstract: A machine for measuring the dimensions of a workpiece, comprising a base te for receiving the workpiece and a mechanical structure carrying a feeler for movement along three orthogonal axes at right angles by means providing for direct measuring of the amounts of movement of the feeler along the axes. Optical deviation measurement means determine the errors due to deformation of the components, lost motion as well as pitch, yaw and/or roll of the movable components. The corrections to be applied to the data delivered by the measuring means are computed and may be made automatically for the display to be free of errors.

Abstract: A device for reading out the position of a movable member comprising a sc carried by that member and having equidistant coded references. Each reference is different from the others. A stationary optical system forms the image of a portion of the scale on a fixed detector. The detector comprises a linear matrix of photo detectors regularly distributed at predetermined intervals and associated with electronic means which identifies the coded reference whose image is formed on the matrix and reads out the serial number of the photo element on which the leading edge of the coded reference is formed.