Patent ID: 7862207

Claim:
A telecentric on-axis darkfield (TOAD) lighting device comprising: a plurality of elongated illumination sources arranged on a planar surface, each of the plurality of elongated illumination sources comprising a first dimension and a second dimension within a plane parallel to the planar surface, wherein the first dimension is longer than the second dimension, and wherein the plurality of elongated illumination sources are arranged in: a first circular array of the elongated illumination sources, wherein the first dimension of each elongated illumination source in the first circular array is arranged radially within the plane with respect to a center point, the first circular array located at a first radius from the center point; and a second circular array of the elongated illumination sources, wherein the first dimension of each elongated illumination source in the second circular array is arranged tangentially within the plane with respect to the center point, the second circular array located at a second radius from the center point.