Method and device for inspecting containers moved on a rectilinear path

A device for inspecting containers moved in a conveying plane with a rectilinear path, this inspection device comprising:

• a first inspection station comprising:
• a first light source along a first side of the path, comprising an emitting surface having a plane of symmetry perpendicular to the path and extending, on the one hand, in height in a vertical direction normal to the conveying plane and, on the other hand, over a total angular width following a concave curve, the emitting surface being composed of a plurality of elementary light sources controlled so as to define at least three illumination zones having at least one first identical illumination configuration;
• at least three image sensors with total observation fields and disposed with optical axes in different directions along a second side of the path opposite the first side, in order to each have, during an image acquisition of a container present in its total observation field, an observation direction passing through the optical centre and the central axis of the container, the observation directions for the image sensors being different and adjusted to recover the light coming from an associated illumination zone;
• a second inspection station located downstream of the first inspection station in the direction of movement of the containers, this second inspection station comprising:
• a second light source along the second side of the path, comprising an emitting surface having a plane of symmetry perpendicular to the path and extending, on the one hand, in height in a vertical direction normal to the conveying plane and, on the other hand, over a total angular width following a concave curve, the emitting surface being composed of a plurality of elementary light sources controlled so as to define at least three illumination zones having at least one first identical illumination configuration;
• at least three image sensors with total observation fields and disposed with optical axes in different directions along the first side of the path, in order to each have, during an image acquisition of a container present in its total observation field, an observation direction passing through the optical centre and the central axis of the container, the observation directions for the image sensors being adjusted to recover the light coming from an associated illumination zone, the observation directions for the image sensors of the second inspection station being mutually different straight lines and different from the observation directions of the image sensors of the first inspection station;
• and a control system of the light sources and the image sensors configured so that when a container in movement is successively located substantially centred on an observation direction of each of the image sensors, in order for each of said image sensors to acquire at least one image of the container illuminated by the associated illumination zone controlled to be switched on successively during the acquisition, having at least the first illumination configuration, the elementary light sources of the illumination zones being controlled in such a way that:
• the at least three illumination zones of each inspection station associated with the image sensors have identical angular widths;
• the at least three illumination zones of each inspection station associated with the image sensors extend with a symmetric angular width relative to the corresponding observation direction;
• and at least two angularly neighbouring illumination zones of each inspection station, have a common illumination portion considering that said two illumination zones are not simultaneously illuminated.