A touch panel that has a front surface, a rear surface, a plurality of edges and an interior volume. An energy source is positioned in proximity to a first edge of the touch panel and is configured to emit energy that is propagated within the interior volume of the touch panel. A diffusing reflector is positioned in proximity to the front surface of the touch panel for diffusively reflecting at least a portion of the energy that escapes from the interior volume. At least one detector is positioned in proximity to the first edge of the touch panel and is configured to detect intensity levels of the energy that is diffusively reflected across the front surface of the touch panel. Preferably, two detectors are spaced apart from each other in proximity to the first edge of the touch panel, to allow calculation of touch locations using simple triangulation techniques.