Patent ID: 7576769

Claim:
A method of inspecting a positional deviation in a predetermined XY-plane of a top position of a convex surface of a protruding portion formed on a flat member and a deepest position of a concave surface constituting a back surface of the convex surface, the method comprising: applying light to the concave surface from below a portion assumed to be a center of the concave surface of the protruding portion in a direction toward the predetermined XY-plane and photographing an image obtained through reflection of the light; obtaining coordinates in the predetermined XY-plane of the deepest position of the concave surface based on the image; photographing the convex surface of the protruding portion by a front camera having an image taking optical axis parallel to the predetermined XY-plane and directed toward the flat member; obtaining coordinates in the predetermined XY-plane of the top position of the convex surface based on an image obtained by the front camera; photographing the convex surface of the protruding portion by a side camera having an image taking optical axis parallel to the predetermined XY-plane, directed toward the flat member, and different from the image taking optical axis of the front camera; obtaining coordinates in the predetermined XY-plane of the top position of the convex surface based on an image obtained by the side camera; and comparing the coordinates in the predetermined XY-plane of the deepest position of the concave surface with the coordinates in the predetermined XY-plane of the top position of the convex surface.