The invention relates to a method for treating a silicate-type glass comprising alkali and alkaline-earth metal oxides or d.sup.10 or IIIA metal oxides, said method comprising at least the following steps: (a) incorporation of nitrogen into the surface of the glass; and (b) thermal poling treatment of the material obtained in (a), under a chemically inert controlled atmosphere. The invention also relates to the material produced by said method.

An apparatus for continuous electro-thermal poling of glass or glass ceramic material, includes a lower support conveying and contacting electrode structure, an upper contacting electrode structure positioned above the lower support structure, and one or more DC bias voltage sources connected to one or both of the upper contacting structure and the lower support structure. A process for continuous electro-thermal poling of glass or glass ceramic sheets or substrates includes heating the sheet or substrate, feeding the sheet or substrate continuously or continually, while applying a DC voltage bias, and cooling the sheet or substrate to within 0-30° C. of ambient temperature.

A device for inducing by thermal poling a spatially controlled refractive index gradient inside at least one amorphous inorganic material to be treated, includes a structured electrode arranged on the surface or in proximity to the surface of the material to be treated; and at least one dielectric material. The structured electrode includes at least one conductive zone and at least one non-conductive zone and it is confined between the amorphous inorganic material to be treated and the dielectric material.

A glass article includes a first surface, a second surface which is opposite the first surface, a first compressive region which extends to a first compression depth in a thickness direction from the first surface, a second compressive region which extends to a second compression depth from the second surface, and a tensile region which is disposed between the first compressive region and the second compressive region. A stress profile of the first compressive region includes a first point and a first inflection point, the first inflection point is located between the first point and the first surface, a depth from the first surface to the first point is 45 to 55% of the first compression depth from the first surface, stress at the first point is greater than 50% of compressive stress of the first surface, and a thickness of the glass article is 0.01 to 0.05 mm.

An apparatus for continuous electro-thermal poling of glass or glass ceramic material, includes a lower support conveying and contacting electrode structure, an upper contacting electrode structure positioned above the lower support structure, and one or more DC bias voltage sources connected to one or both of the upper contacting structure and the lower support structure. A process for continuous electro-thermal poling of glass or glass ceramic sheets or substrates includes heating the sheet or substrate, feeding the sheet or substrate continuously or continually, while applying a DC voltage bias, and cooling the sheet or substrate to within 0-30 C. of ambient temperature.

Methods of manufacturing a glass-based article comprise: after mechanical polishing of a glass-based substrate, treating at least one surface of the glass-based substrate for protection of the at least one surface from contamination and/or for removal of contaminants from the at least one surface by a treatment other than ultrasonic cleaning; and exposing the glass-based substrate to an ion exchange treatment after the treating step to form the glass-based article. The treating step includes: exposing the at least one surface to a high pH soaking for removal of contaminants; deionizing the at least one surface for removal of contaminants; and/or applying a temporary coating to the at least one surface for protection of the at least one surface from contamination, and removing the temporary coating prior to the ion exchange treatment step. The ion exchange treatment may comprise a molten salt bath having an increased pH and temperature.

A thermo-electric method for texturing a glass surface including, for example, simultaneously heating a glass substrate to a temperature less than its glass transition temperature and applying a bias across the glass substrate using a template electrode. The applied bias at the processing temperature induces localized ion migration within the glass, which results in the formation in the glass surface of a negative topographical image of the pattern formed in the electrode.

Embodiments of a glass substrate including an alkali-containing bulk and an alkali-depleted surface layer, including a substantially homogenous composition are disclosed. In some embodiments, the alkali-depleted surface layer includes about 0.5 atomic % alkali or less. The alkali-depleted surface layer may be substantially free of hydrogen and/or crystallites. Methods for forming a glass substrate with a modified surface layer are also provided.

A device for inducing by thermal poling a spatially controlled refractive index gradient inside at least one amorphous inorganic material to be treated, includes a structured electrode arranged on the surface or in proximity to the surface of the material to be treated; and at least one dielectric material. The structured electrode includes at least one conductive zone and at least one non-conductive zone and it is confined between the amorphous inorganic material to be treated and the dielectric material.

The invention relates to a method for treating a silicate-type glass comprising alkali and alkaline-earth metal oxides or d.sup.10 or IIIA metal oxides, said method comprising at least the following steps: (a) incorporation of nitrogen into the surface of the glass; and (b) thermal poling treatment of the material obtained in (a), under a chemically inert controlled atmosphere. The invention also relates to the material produced by said method.