Abstract: The present invention relates generally to a method for optical sorting and more particularly, but not by way of limitation, to an apparatus and method for sorting individual objects such as, for example, beans, grains, fruit and the like such that contaminated objects can be separated from non-contaminated objects. The objects are pre-stimulated with a source emitting UV light and are sorted based on the signal emitted by the objects, in particular for sorting Fungus-contaminated objects.

Abstract: An optical sorter for beans and grains, including a detector providing a signal pulse for each of the sampled objects, and a signal processor for receiving and amplifying the pulse. The signal processor measures the amplitude of the amplifier pulse and compares the amplitude value to a predetermined standard value. The pulses are counted up to a predetermined count, and the number of pulses having an amplitude value above the predetermined standard value out of the total number of counted pulses, is counted. The counted number of pulses having an amplitude above the standard value is compared to a preselected number, and the gain of the signal processor is adjusted with a negative feedback signal to adjust toward the preselected number, the counted number of pulses in the next count having an amplitude value at the predetermined standard value.

Abstract: Apparatus for optically sorting small light objects such as beans and/or grains on the basis of size and color. A feeding mechanism separates the objects one from another and delivers them in a free falling condition to an optical analysis means where each object is uniformly illuminated. The analysis is based on the amount and spectrum of reflected light which is conveyed to a pair of light transducers having different response characteristics. The electrical signals developed by the transducers are simultaneously analyzed for absolute values to determine object size and relative value of the integrated signals to determine object coloring.An annular analysis head is employed with the objects being analyzed falling through the central opening. The head is comprised of a pair of annular rings with a predetermined gap between the rings located at the central opening. Plural fiber light conducting rods are uniformly spaced about the circumference of the gap so as to collect light reflected from the object.