Patent ID: 6970620

Claim:
A waveguide for at least one of radiating and receiving electromagnetic radiation, said waveguide comprising a central axis, a circumferential surface which is concentric to said axis and is transmissive only to radiation which impinges said surface at angles greater than a critical angle of total reflection in the waveguide, a distal end defining a proximal direction extending axially away from said distal end, said circumferential surface extending to said distal end, said distal end having a concave spherical surface, and a spherical scatter body fitted into said concave spherical surface, said scatter body having scatter elements arranged at said distal end at least one of on and in said scatter body so that at least one of the following transpires: radiation transmitted by the waveguide toward the distal end is scattered by the scatter elements at least in part in a direction with a proximal component and exits the circumferential surface, and radiation entering the circumferential surface of the waveguide in a direction with a distal component is transmitted by the waveguide at least in part in the proximal direction.