Patent attributes
An optical transducer for determining the presence or absence of liquid or the like in a reservoir includes a housing with a hollow interior and an optical probe that extends through the housing. The optical probe has a central axis, a proximal end positioned in the hollow interior and a distal end positioned outside of the housing. The distal end has first and second measurement surfaces that intersect at a transverse edge. The transverse edge extends at an acute angle with respect to the central axis. A light source is arranged for projecting radiant energy into the optical probe toward the distal end. A photosensor is arranged for detecting radiant energy reflected from the distal end to thereby detect the presence and absence of liquid on the optical probe.
