Abstract: A transparent armor laminate system is described that utilizes a glass-ceramic material as the strike-face material, one or a plurality of intermediate layers, and a backing material. This laminate system offers improved performance with reduced weight over conventional all-glass or all-glass-ceramic transparent armor systems. The glass-ceramic material consists of a glass phase and a crystalline phase, the crystalline phase being selected from a group consisting of beta-quartz, mullite and combinations thereof.

Abstract: This disclosure teaches the use of low density, “open”-structure glasses as backing glasses, behind glass-ceramic strike-faces, in transparent armor composite windows. These low density “open-structure’ glasses are sometimes referred to as “anomalous” glasses. For transparent armor applications both silica, including fused silica, and borosilicate glasses can be used as backing glass. These backing glasses provide improved ballistics performance over that of standard commercial soda lime backing glass. These glasses should be used either in their as-formed state (e.g. float surfaces) or should be finished using a process designed for minimizing sub-surface damage.

Abstract: The invention is directed to transparent glass-ceramic materials for use in transparent armor systems. Applications include armor systems for ground vehicles and aircraft as well as personal protective equipment. The glass-ceramic materials according to the invention exhibit a ballistic limit vs. areal density line slope of 1.0 or greater, preferably 1.1 or greater and more preferably 1.2 or greater. The crystalline phase of the glass ceramic materials may include ?-quartz, spinel, spinel solid solutions, mullite and phases known in the art to be transparent.

Abstract: A transparent armor laminate system includes a plurality of sub-stacks separated by an interlayer. The sub-stacks include a plurality of layers including a glass ceramic front strike-face layer, a backing layer comprising a spall-resistant material, and at least one glass layer laminated between the strike-face and backing layers. The interlayer isolates cracks between sub-stacks, and may include an isolating material such as a polymer, gas, or liquid. The laminate system offers improved performance with reduced weight over conventional all-glass or all-glass-ceramic transparent armors.

Abstract: The present invention describes an article that is substantially free of optical distortion and a method for eliminating or substantially reducing the need for conventional polishing of transparent objects. The article comprises a laminate of an optically distorting transparent object bonded with an adhesive to at least one transparent object that has a distortion-free surface. The indices of refraction of the adhesive and the objects are preferably within 0.2. The method includes adhesively bonding an optically distorting transparent object to one or more transparent objects having distortion-free surfaces so that the distortion-free surface is exposed.