Optical inspection unit for quality control - has TV camera scanning tested and reference objects for correcting video signal

摘要

Elimination of incorrect inspection of objects is ensured by comparing light intensity reflected from a reference unit with that due to the tested object. TheTV camera (3) takes the image of the reference object (1) using a white paper (5) for the calibration. The viewing field of the camera is illuminated by light source (2). The signal dereived from the reflection from the calibration paper (5) is fed to a circuit (4) which ensures the correction of the video signal from the camera. The corrected video signal is then discriminated against the video signal derived from the tested object by the comparator (43) for deciding whether a match exists between the tested object and the reference object. The method provides reliable inspection irrespective of ambient conditions.