Glass-bending apparatus and method

A sag-bending glass mold comprising:

• a rectangular perimeter comprising first and second longitudinal members extending in a first direction and first and second lateral members extending in a second direction, the first and second directions substantially perpendicular to each other, each of the first and second longitudinal members coupled to each of the first and second lateral members;
• a plurality of lateral ribs extending substantially parallel to the second direction, a first of the plurality of lateral ribs coupled to the first longitudinal member and a second of the plurality of lateral ribs coupled to the second longitudinal member;
• a plurality of longitudinal ribs extending substantially parallel to the first direction, a first of the plurality of longitudinal ribs coupled to the first lateral member and a second of the plurality of longitudinal ribs coupled to the second lateral member, each of the plurality of longitudinal ribs coupled to at least one of the plurality of lateral ribs, each of the longitudinal ribs having an upper surface that is curved about the second direction;
• and
• a capping surface disposed on the upper surface of each of the first and second longitudinal members and each of the first and second lateral members, the capping surface on the first and second longitudinal members having a flattened upper surface or a curved upper surface that is curved about the first direction, wherein the capping surface has a coefficient of thermal conduction of at most 100 W/(m·K) and a coefficient of volumetric thermal expansion of at most 10×(10−6/K),
• wherein the capping surface is adapted to shape a sheet of glass such that, when heated, the sheet of glass sags towards and is shaped by the curved upper surface of the capping surface.