Abstract: Emitters and detectors are positioned in proximity to a display screen. Emitters emit energy beams that are diverged across the surface of the display screen. Emitters may be activated/deactivated in sequence, rapid enough to substantially ensure that several energy beams are interrupted by a touch of the display screen. Detectors receive energy beams over a range of angles and generate detection signals upon detecting energy beams. Detection maps are generated based on detection signals. Detection maps indicate which detector should receive an energy beam from which emitter at any point in time. Detections maps are compared to determine that energy beams have been interrupted by a touch. Based on the interrupted energy beams, the location of the touch on the display screen may be determined. The invention serves to reduce the number of emitters and detectors required in a touch panel display system and/or increase the sensitivity and accuracy thereof.