Patent ID: 8285026

Claim:
An inspection system for inspecting irregular objects in a stream of products based on forming a scan line by means of at least one light source, directing light along the scan line, and measuring scattered light or directly reemitted light obtained from objects in the illuminated product stream; the inspection system comprising: means for scanning the stream of products along the scan line, the scanning means comprising a focusing means for concentrating the light in at least one dimension; a detecting means configured to detect light beams reemitted by the product stream upon scanning, which detection means produces an electrical signal proportional to the detected light beams; the detecting means comprising a focusing means defining an image plane for forming a spatial image of the stream of products along the scan line, the focusing means being configured to focus the image in at least one dimension and being oriented towards the scan line such that points on the scan line form a projected scan line along a direction x p in the image plane, and the detecting means further comprising a spatial filtering means operating in the image plane, the spatial filtering means being configured to filter the image in substantially only the direction perpendicular to the direction of the projected scan line such that a field of view of the detecting means is delimited to predominantly directly reemitted light or predominantly scattered light.