Patent ID: 7573129

Claim:
A circuit module comprised of: first and second leaded packaged integrated circuits in stacked disposition with the first leaded package being disposed above the second leaded package, each of which first and second leaded packaged integrated circuits having a body emergent from which are leads that each have a shoulder and foot, the shoulders each having a head; a first interposer for electrical connection between the first and second leaded packaged integrated circuits, the first interposer having a dark portion and a light portion defined on a lower planar surface of the interposer and delineable with an imaginary line K, with the light portion being more reflective of light than is the dark portion and the first interposer having an external section and an internal section disposed on different sides of a line L defined by termini of a plurality of the feet of the leads of the first leaded packaged integrated circuit, the external section of the first interposer being further from the first packaged integrated circuit than is the internal section, and imaginary line K being closer to the body of the second packaged integrated circuit than is line L, wherein the dark portion extends through the line L.