High-impact, transparent, distortion-free polymeric sheet and windshield

A high-impact, transparent windshield comprising:

• a base sheet of transparent polycarbonate material having a glass transition temperature and a melt temperature, the base sheet being a windshield comprising a first portion and a second portion;
• wherein the first portion has a shape created by a non-contact forming operation occurring at a temperature above the glass transition temperature and below the melt temperature of the transparent polycarbonate material;
• and
• wherein the second portion is a peripheral portion, said second portion has a non-planar shape as its outermost edge created by a contact forming operation occurring at a temperature above the glass transition temperature and below the melt temperature of the polycarbonate material, said second portion non-planar outermost edge having a non-planar contour;
• and
• wherein when said sheet rests on a plane, said second non-planar portion contour is spaced away from said plane such that portions of the periphery including said second non-planar portion contour are raised above and not in contact with said plane.

A high-impact, transparent windshield comprising:

• a base sheet of transparent polycarbonate material having a glass transition temperature and a melt temperature, the base sheet being a contoured non-planar windshield comprising a first portion and a second portion;
• wherein the first portion has a shape created by a non-contact forming operation occurring at a temperature above the glass transition temperature and below the melt temperature of the transparent polycarbonate material;
• wherein the second portion has a shape created by a contact forming operation occurring at a temperature above the glass transition temperature and below the melt temperature of the polycarbonate material;
• said second peripheral portion has an outermost edge defined by a pair of opposing surfaces and a terminal end surface connecting the pair of opposing surfaces at the outermost edge, and said opposing surfaces are on a non-perpendicular angle with respect to said end surface;
• and
• wherein when said sheet rests on a plane, said second non-planar portion contour is spaced away from said plane such that portions of the periphery including said second non-planar portion contour are raised above and not in contact with said plane.