Abstract: An automatic optoelectronic inspection device is located at a position downstream from a cigarette making machine and upstream from cigarette packaging machinery, and cigarettes are conveyed in groups to the inspection device where each group is inspected. The inspection device includes a plurality of photodetectors arranged so that there is a one-to-one correspondence between the position of a photodetector and the position occupied by each cigarette in a normally formed group. Each photodetector includes a light-emitting source for illuminating the end portion of a cigarette and a photoelectric transducer for sensing light reflected from the end portion of a cigarette in registration with the photodetector. The power to the light-emitting sources is controlled in such a way that the intensity of the light emanating from each light-emitting source is modulated at a high frequency.