Abstract: The present invention is directed at a family of glasses capable of absorbing UV radiation and filtering yellow light in the visible region of the spectrum, the family of glasses having a composition consisting essentially, in terms of weight percent on the oxide basis, of: 55-95.7% SiO2, 0-28% B2O3, 0.5-18% Al2O3, 0-4% SrO, 0-13% BaO, 0-13% CaO, 0-8% MgO, 0-7.5% Na2O, 0-9.5% K2O, 0-1.5% Li2O, 0-1.5% Sb2O3, 0.4-4.5% Nd2O3, and 0.1-1% CeO2. Glasses of the present invention are capable of employment as envelopes for tungsten-halogen lamps and other high temperature light sources, as well as sealed-beam incandescent headlights.

Abstract: A polishing application uses alkali, colloidal silica for polishing silicate-based glasses. Preferably, the silica solutions are adjusted to a pH of or above 10. The polished silicate-based glass surfaces have surface finishes consistently below 2 Å Ra. The unique method first polishes a surface of the substrate with an aqueous solution of at least one metal oxide abrasive and further polishes the surface of the substrate with an alkali aqueous solution of colloidal silica. Preferably, to the final smoothness of 2 Å Ra or less.

Abstract: This article is a glass substrate having a coating thereon. The coating strongly absorbs certain ultraviolet radiation. The preferred coating absorbs ultraviolet radiation at wavelengths ranging from 230 up to at least 280 nm while providing high transmission throughout a region of visible wavelengths. The preferred coating consisting essentially of three layers, wherein the first layer adjacent the substrate is a mixture of SiO2 and TiO2; the second layer is TiO2 and the third layer farthest from the substrate is SiO2.

Abstract: A glass-ceramic which is substantially and desirably totally transparent, and which contains a willemite predominant crystal phase within the ternary Mg2SiO4—Zn2SiO4—Li4SiO4 system. The glass-ceramic is formed from precursor glasses having the following compositions, in weight percent on an oxide basis, of 25-60 SiO2, 4-20 Al2O3, 20-55 ZnO, 0-12 MgO, 0-18 K2O, 0-12 Na2O, 0-30 GeO2, with the condition that &Sgr;K2O+Na2O≧5. The glass-ceramic may be doped with up to 1 wt. % Cr2O3 to impart optical activity thereto.

Abstract: A glass-ceramic which is substantially and desirably totally transparent, and which contains a predominant crystal phase of forsterite. The glass-ceramic is formed from precursor glasses having the following compositions, in weight percent on an oxide basis: SiO2 30-60; Al2O3 10-25; MgO 13-30; K2O 8-20; TiO2 0-10; and GeO2 0-25. The glass-ceramic may be doped with up to 1 wt. % chromium oxide to impart optical activity thereto.

Abstract: A gain medium for use in optical amplifiers or laser oscillators is disclosed. The gain medium includes a transition-metal doped glass-ceramic material having a crystal phase and a glass phase. The crystal phase is formed in situ in the glass phase, with the transition metal ions preferentially partitioning into the crystals from the glass phase. The crystals so formed have a size of less than 50 nm, and the transition metal ions within them are capable of lasing at a wavelength within the range of about 900 to 3000 nm. Also disclosed are amplifier and laser oscillator configurations, where the glass-ceramic gain medium is applied in a variety of configurations. Also disclosed is a method of amplifying a signal of light wherein the glass-ceramic gain medium is pumped with light energy so as to excite the transition metal ions, and the signal of light is transmitted through the gain medium while the transition metal ions are excited, whereby the signal of light is amplified.

Abstract: Method of patterning or forming color gradients and/or designs on a glass surface are disclosed. Patterns are formed by depositing a film of metal on at least one surface of the glass; forming a layer of photoresist over the metal; exposing the article to light through a mask which contains a desired pattern; developing the piece to remove the exposed photoresist to reveal the underlying metal; removing the underlying metal to reveal the underlying glass; and removing the unexposed photoresist to reveal the underlying metal. To form color gradients or color patterns, the glass article is further treated in hydrogen at a temperature in the range of 300-600.degree. C. to effect the desired surface coloration.

Abstract: The invention relates to a strong UV absorbing glass consisting essentially of, expressed in cation percent, 15-30% SiO.sub.2, 50-60% B.sub.2 O.sub.3, 2-5% Al.sub.2 O.sub.3, 0-6% Li.sub.2 O, 0-3.0% Na.sub.2 O, 14-20% K.sub.2 O, 0.5-1.0% CuO, 0.4-0.7% SnO.sub.2, 0.5-1.5% Cl, and 0.7-1.5% Br. An essentially haze-free version of the glass is disclosed. A UV absorbing coating material made by suspending ground particles of the inventive glass in a suitable matrix is also disclosed.