Abstract: The individual outputs of a large laser diode array are combined using an optical transformer of diffractive optics. To allow for the tolerances in the laser array and combining optics required for mass production, the system further includes corrector optics. The corrector optics includes individual lens elements which are fabricated to provide specific correction of faults in the individual lasers and associated combining optics resulting from manufacturing tolerances. The preferred corrector lenses include diffractive lenses fabricated by laser milling.