Patent attributes
An optical prism that includes an interlock structure that precisely couples to a complementary structure of a refractive lens. For precision, the interlock structure may be formed at the same time and using the same technique as the optical surface of the prism. The interlock structure provides high accuracy when assembling a folded lens system by precisely aligning the object side optical surface of the lens with the image side optical surface of the prism so that the optical axis is centered in the lens. The prism may have refractive power. A portion of the object side surface may be coated with an opaque material to provide an aperture stop at that surface.