Provided is glass with high temperature stability, a low coefficient of thermal expansion and a high mechanical strength, a light guide plate including the glass to replace the conventional PMMA and metal frame, and fabricating methods thereof. The glass according to the present disclosure is borosilicate glass containing 7585 wt % of SiO.sub.2, 515 wt % of B.sub.2O.sub.3, 05 wt % of Al.sub.2O.sub.3, R.sub.2O 17 wt % where R is at least one of Li, Na and K, and <0.005 wt % of Fe.sub.2O.sub.3 and having the redox ratio 0.5 or more. This glass maintains luminance and has an excellent color difference reduction effect when used in a light guide plate.

Provided is glass with high temperature stability, a low coefficient of thermal expansion and a high mechanical strength, a light guide plate including the glass to replace the conventional PMMA and metal frame, and fabricating methods thereof. The glass according to the present disclosure is borosilicate glass containing 7585 wt % of SiO.sub.2, 515 wt % of B.sub.2O.sub.3, 05 wt % of Al.sub.2O.sub.3, R.sub.2O 17 wt % where R is at least one of Li, Na and K, and <0.005 wt % of Fe.sub.2O.sub.3 and having the redox ratio 0.5 or more. This glass maintains luminance and has an excellent color difference reduction effect when used in a light guide plate.

A glass substrate for a high-frequency device, which contains SiO.sub.2 as a main component, the glass substrate having a total content of alkali metal oxides in the range of 0.001-5% in terms of mole percent on the basis of oxides, the alkali metal oxides having a molar ratio represented by Na.sub.2O/(Na.sub.2O+K.sub.2O) in the range of 0.01-0.99, and the glass substrate having a total content of alkaline earth metal oxides in the range of 0.1-13% in terms of mole percent on the basis of oxides, wherein at least one main surface of the glass substrate has a surface roughness of 1.5 nm or less in terms of arithmetic average roughness Ra, and the glass substrate has a dielectric dissipation factor at 35 GHz of 0.007 or less.

A glass substrate for a high-frequency device, which contains SiO.sub.2 as a main component, the glass substrate having a total content of alkali metal oxides in the range of 0.001-5% in terms of mole percent on the basis of oxides, the alkali metal oxides having a molar ratio represented by Na.sub.2O/(Na.sub.2O+K.sub.2O) in the range of 0.01-0.99, and the glass substrate having a total content of alkaline earth metal oxides in the range of 0.1-13% in terms of mole percent on the basis of oxides, wherein at least one main surface of the glass substrate has a surface roughness of 1.5 nm or less in terms of arithmetic average roughness Ra, and the glass substrate has a dielectric dissipation factor at 35 GHz of 0.007 or less.

An optical device comprises a first polariscope and a set of first photodetectors and an optical retardation generator. The device is configured to analyze the quality of a glazing.

An optical device comprises a first polariscope and a set of first photodetectors and an optical retardation generator. The device is configured to analyze the quality of a glazing.

Methods and systems are provided for automated shaping of a glass sheet. The methods comprise preheating the glass, bending the glass through selective, and focused beam heating through the use of an ultra-high frequency, high-power electromagnetic wave, and computer implemented processes utilizing thermal and shape (positional) data obtained in real-time, and cooling the glass sheet to produce a glass sheet suitable for use in air and space vehicles.

Methods and systems are provided for automated shaping of a glass sheet. The methods comprise preheating the glass, bending the glass through selective, and focused beam heating through the use of an ultra-high frequency, high-power electromagnetic wave, and computer implemented processes utilizing thermal and shape (positional) data obtained in real-time, and cooling the glass sheet to produce a glass sheet suitable for use in air and space vehicles.

A strengthened glass article (100), such as a substrate for a p-Si based transistors, includes first and second glass cladding layers (104, 106) and a glass core layer (102) disposed therebetween. A coefficient of thermal expansion [CTE] of each cladding layer (104, 106), which can be made of the same glass, is at least 110.sup.7 C..sup.1 less than that of the core layer (102). Each of the core and cladding layers has a strain point less than 700 C. A compaction of the glass article (100) is at most about 20 ppm [see FIG. 1]. A method includes forming a glass article and/or heating a glass article to a first temperature of at least about 400 C. The glass article has a glass core layer (102) and a glass cladding layer (104, 106) adjacent to the core layer. The glass article is maintained at a temperature within a range of from 400 C. to 600 C. for a holding period from 30 to 90 minutes and subsequently cooled to a temperature of at most 50 C. over a cooling period from 30 seconds to 5 minutes. The glass article (100) for heat strengthening may have been produced by the fusion overflow down draw process, e.g. as depicted in FIG. 3.

A strengthened glass article (100), such as a substrate for a p-Si based transistors, includes first and second glass cladding layers (104, 106) and a glass core layer (102) disposed therebetween. A coefficient of thermal expansion [CTE] of each cladding layer (104, 106), which can be made of the same glass, is at least 110.sup.7 C..sup.1 less than that of the core layer (102). Each of the core and cladding layers has a strain point less than 700 C. A compaction of the glass article (100) is at most about 20 ppm [see FIG. 1]. A method includes forming a glass article and/or heating a glass article to a first temperature of at least about 400 C. The glass article has a glass core layer (102) and a glass cladding layer (104, 106) adjacent to the core layer. The glass article is maintained at a temperature within a range of from 400 C. to 600 C. for a holding period from 30 to 90 minutes and subsequently cooled to a temperature of at most 50 C. over a cooling period from 30 seconds to 5 minutes. The glass article (100) for heat strengthening may have been produced by the fusion overflow down draw process, e.g. as depicted in FIG. 3.