PERIMETER WITH NON SPHERICAL BOWL

摘要

A perimeter is disclosed in which the projection surface of the bowl includes a hemispherical (H) section bounded by a cylindrical perimeter (C) to impart to the interior projection surface of the instrument a "bullet shaped" profile (S). The perimeter of preferred dimension includes a reduced diameter hemisphere occupying the central 45 DEG of solid angle from the fixated patient's eye (E). The cylindrical perimeter is joined to the hemisphere and is generated about a cylindrical axis commencing at the spherical center of the hemisphere and extending outward normally from the hemisphere to the point of patient eye placement. The diameter of the cylinder matches and forms a projection continuum with the radius of the hemisphere.