DETECTOR FOR FLAW OF GLASS BOTTLE

摘要

PURPOSE:To eliminate the disturbance owing to deterioration, etc. of a light source lamp and to make signal processing sure and easy by providing a standard scattering plate which is irradiated with the light from a light projector, providing a photodetector for correction on a photodetector side and correcting a flaw detection signal or a reference value for comparison with the output of the photodetector for correction. CONSTITUTION:A standard scattering plate 18 is beforehand estimated of the percentage quantity beta of the scattered light with respect to the quantity of the incident light and is so disposed that said plate is irradiated with a part of the parallel luminous flux from a light projector 3 and that the light scattered by said plate is introduced into a photodetector 4. The photodetector 4 is provided with a slit 19 and a photodetector 20 as a photodetector for correction to be introduced therein with the light scattered from the plate 18 in addition to a slit 12 and a photodetector 13 for flaw measurement. The electrical signal output of the photodetector 20 passes through an amplifier circuit 21 and is made into the input Vc for a setting circuit 22 for percentage quantity of scattered light. The circuit 22 calculates the output Vo(=VcXbeta). The output Vo multiplied by a reference value X for comparison in a correction circuit 23 for the reference for comparison as a corrected value Vs(VoXX) which is used as the reference value for comparison in a comparing decision circuit 15. Said value is compared with Vm which is the detection output from the photodetector 13 side.