The invention refers to an optical inspection system for an inspection of an object in form of a leaded IC component, wherein the object is positioned in an overlapping relationship with an aperture of a datum and illuminated by a lateral diffuse light source, thereby projecting contour images of the object and of a reference contour of the reference edge through the aperture in several projection directions. An optical side prism and a center prism is provided to receive the projection light under two different incident angles thus defining two different projection paths so that a three dimensional image can be captured by analyzing the light of these two projection paths coming from one object point. The side prism and the center prism are designed and arranged such that the projection paths of the first and second projections have the same optical length between the lead-including contour of the object and an imaging plane of the system.
