Patent ID: 6445518
Filing Date: 2002-09-03
Classification: H05K

Abstract:
Apparatus for providing first and second backlit images of a semiconductor device edge and leads extending therefrom, said images representative of first and second viewing angles corresponding to first and second different optical axes as measured in a plane perpendicular to said device edge, comprising:at least one illuminator providing diffuse backlight illumination of said device edge and leads along said first and second optical axes; a triangular prism having a first optical surface facing said device edge and intersecting said first and second optical axes, a second optical surface forming an acute angle with said first optical axes, and a third optical surface, said first and second surfaces being at selected angles to said first and second optical axes to cause a first image of said device edge and leads along said first optical axis to be reflected by said second optical surface and emerge from said third optical surface in direction corresponding to a third optical axis and to cause a second image of said device edge and said leads along said second optical axis to be reflected by said second optical surface and said first optical surface and emerge from said third optical surface in a direction corresponding to said third optical axis; and a camera arranged to capture said first and second images along said third optical axis.