An apparatus for detecting a pointer includes a waveguide and a touch
surface over the waveguide on which pointer contacts are to be made. At
least one reflecting device extends along a first side of the waveguide
and touch surface. The reflecting device defines an optical path between
the interior of the waveguide and the region of interest above the touch
surface. At least one imaging device looks across the touch surface and
into the waveguide. The imaging device captures images of the region of
interest and within the waveguide including reflections from the
reflecting device.