An image forming apparatus is capable of forming a clear image by using laser beams projected from a plurality of laser light sources. The collet is configured to suck a surface of a semiconductor chip. For each identified class a sketch table containing a plurality of parallel hash tables is created. The two bearings are secured on the baseplate and the mounting board, respectively. The method includes applying a pigmented material proximate the retroreflective layer, the pigmented material preferably forming a plurality of parallel stripes oriented substantially in at least one of the web direction and a direction orthogonal to the web direction. The mechanical connection required for producing the electrical contacts between the semiconductor chip and the supporting substrate ensues only temporarily.