Chemical imaging by a computer screen aided scanning light pulse technique

A scanning light pulse technique (SLPT) for the generation of selective chemical images is demonstrated, using a broadly available programmable light source provided by a standard cathode-rays tube computer screen, which supplies two-dimensional micropositioning and intensity modulation. The concept is tested with a metal-oxide-semiconductor capacitor with catalytic gates of platinum and palladium spatially distributed in transversal directions, which produce distinctive response patterns upon hydrogen or ammonia exposures. The nonlaterally resolved images formed by the weighted contribution of the chemically sensitive areas of the gate, subsequently highlighted by the exciting light along its scanning path, retains the ability of SLPT to generate distinctive chemical images. (C) 2002 American Institute of Physics.