OPTICAL MEASURING APPARATUS

摘要

PROBLEM TO BE SOLVED: To provide an optical measuring apparatus which can be made compact and whose costs can be reduced. SOLUTION: A photodetector 5 is arranged and installed in such a way that its optical axis J2 is at right angles to the longitudinal direction of a conveyor 10. A projector 4 is arranged in such a way that its optical axis J1 crosses the optical axis J2 of the photodetector 5 nearly in the center in the width direction of the conveyor 10 and that an angle D which is formed by the optical axis J1 of the projector 4 and by the optical axis J2 of the photodetector 5 is at more than 15 deg. to 20 deg.. A sidewall 9 and a sidewall 9 are erected and installed along the conveyor 10 on both sides of the conveyor 10. Openings in a required diameter are formed in a part facing the projector 4 and the photodetector 5 at the sidewalls 9, 9 and in a part facing a light source 31 and a photosensor 32 at the sidewalls 9, 9 so as to pass a light beam. A low light reflection plate 8 is attached to a part in which light from the projector 4 can be reflected on the sidewall 9 on the side of the photodetector 5 and in the part excluding the openings.