Patent ID: 8164746

Claim:
An optical inspection method for determining the presence of defects on the surface (s) of the collar ( 3 ) of a transparent or translucent container ( 4 ), the method including the following steps: illuminating at least the surface of the collar (s) of the container ( 4 ) by means of an illuminating system, forming an image of said collar surface, and analyzing the image so as to determine the presence of a defect on the surface of the collar, characterized in that: illumination is performed by means of at least one illuminating system ( 11 , 20 ) providing any point of a surface encompassing the surface (s) of the collar ( 3 ), with quasi-constant illumination according to the totality or part or the incidences included in at least one portion of the 2π steradian solid angle, blocking is performed of at least one portion of the light rays illuminating outside the surface (s) of the collar ( 3 ) and capable of causing stray reflections in the image of the collar.