. . . "For example, the passageway may be slanted so as to allow light to pass therethrough at an angle A of about 65 degrees (or more or less, such as plus or minus about 5 degrees or thereabouts) relative to the generally vertical plane of the planar back plate portion and reflective element (i.e., about 25 degrees outboard from a line extending perpendicularly from the plane of the planar back plate p" .