OPTICAL SYSTEM

Medicinal-capsule inspection apparatus. Successive capsules spun on their axis in an inspection position are illuminated by intense light originating at a single lamp filament and reflected onto the capsule from a mirror in the form of a narrow band cut from an ellipsoid and positioned so that the filament is adjacent to one focus and the capsule adjacent to the other focus. The mirror wraps around the capsule endwise and produces on the capsule, as seen by a side-viewing lens and two end-viewing lenses, a narrow well-defined and continuous glare line area which is unique in that it curves over the ends substantially to the axis. The lenses project images of the capsule in side and end elevation. Masks at the image planes block the glare light from acceptable capsules, but contain apertures in selected relation to the image glare light areas, which pass light specularly reflected from defects in selected observation areas on the spinning capsules. Such light acts on light sensors behind the apertures to generate electrical control signals which provide inspection output information.