Abstract: The sensor comprises a structured light source (5, 6, 7) which is adjustable so as to interchange the positions of contrasting areas of the pattern it provides, a detector (1) which comprises an array of detector elements having dimensions matched to the pattern produced by the light source, an optical system (2, 8) for projecting a primary image of the light source pattern onto an object (3) that is to be sensed and for forming a secondary image on the detector (1) of the primary image thus formed on the object (3), positioning means (4) for moving at least part (2) of the optical system so as to vary the focussing of the primary image on the object (3) and processing means (12) for analyzing signals produced by the detector (1) in conjunction with information on the adjustment of the optical system (2, 8). The optical arrangement is `confocal` so that, when the primary image is in focus on the object (3), the secondary image on the detector (1) is also in focus.

Abstract: The device comprises a structure (1) supporting a light beam source (2), a beam guide and a camera assembly (3), the light beam source (2) being arranged to direct an outgoing beam of light (I) into the beam guide which projects the outgoing beam (P) onto a target surface to sweep the beam around an endless path (E) on the target surface, scans synchronously around the endless path (E) to receive light returning from the portion of the path (E) illuminated by the outgoing beam (P), and directs the returning light (P) onto a light sensor (12) provided in the camera assembly (3); the beam guide comprising a rotatable wedge prism (5) arranged such that the outgoing beam (2) is transmitted through relatively inclined surfaces (9, 10) of a projecting element of the prism (5) as it is rotated to direct the beam (P) to sweep around the endless path (E) and the light returning from the portion of the path illuminated by the beam (P) is received through relatively inclined surfaces (9, 10) of a receiving element of th

Abstract: A fan beam of light from a source (L) is directed across the edge of a car body window frame section (10) with an external reflective corner (11) and an internal reflective corner (12). The corners reflect sharp spots of light (S1) and (S2) respectively into a detector (D) which produces an output waveform (FIG. 2) in which sharp pulses (P1, P2) correspond to the spots of light. It is easy to discriminate against other pulses (P3) arising from stray reflections, e.g. the multiple reflection (13, R3). The positions of the pulses (P1 and P2) enable the positions of the corners to be calculated. Two detectors and/or or two light sources may be used to increase the amount of data available so as to allow a complete solution for the coordinates of the centers of curvature (C1, C2) of the corners relative to the detectors and the radii of curvature of the corners.

Abstract: Apparatus to control the automatic placing of material along a junction between surfaces with reference to the form and position of the junction including a tool controllably movable to deposit material progressively along the junction in response to a control signal, an imager linked to the movement of the tool to produce an image of the surfaces and junction, a system to extract from the image that portion unambiguously defining the junction form and position, an arrangement responsive to this image portion to derive the control signal to control the tool to move in a required manner along the junction to deposit material.

Abstract: Apparatus to control the automatic placing of material along a junction between surfaces with reference to the form and position of the junction including means controllably movable to deposit material progressively along the junction in response to a control signal, means linked to the movement of the means to deposit material to produce an image of the surfaces and junction, filter means to remove from the image information resulting from illumination at other than a specific wavelength with a tapped delay line to provide a specific impulse response, means to extract from the image that portion unambiguously defining the junction form and position, means responsive to said image portion to derive said control signal to control the means to deposit material to move in a required manner along said junction to deposit material.