The invention, in accordance with one aspect, is an optical assembly including
a substrate, a light emitting device mounted over a major surface of the substrate
and having a back face, at least one channel formed in the substrate near the back
face of the light emitting device, and at least one photodetector optically coupled
to the light emitted from the back face. The channel includes at least one surface
adapted to receive a portion of the back face light and reflect it away from the
photodetector so that the photodetector receives primarily direct light from the
back face.
