Methods of characterizing ion-exchanged chemically strengthened Li-containing glasses include: a) measuring a mode spectrum of the glass sample; b) using the mode spectrum, estimating a first contribution to the center tension associated with a spike region and estimating a second contribution to the center tension due to a deep region only, wherein the deep region is assumed to follow a power-law stress profile; and c) determining a total center tension by adding of the first and second contributions to the center tension. The methods can be used for quality control during manufacturing of glass samples by comparing the total center tension to a center tension specification that provides optimum strength and durability.

A method for measuring the thickness of glass containers includes the following steps:

choosing to measure the radiation emitted by the container from a first side and a second side of the container diametrically opposite to each other;

choosing to measure the radiation emitted by the container in a first spectral band in a range between 2,800 nm and 4,000 nm and in a second spectral band;

simultaneously measuring, from each side of the container, the intensity of the radiation coming from the walls in the first spectral band and in the second spectral band; and

determining at least the thickness of the first wall and of the second wall (2.sub.2), from the measurements of the intensity of the radiation coming from the first wall in the first and second spectral bands and from the second wall in the first and second spectral bands.

An accelerated weathering device, system and method is provided for rapidly weather testing insulating glass units (IGUs). The accelerated weathering system can include an air sealed vessel that can removably house an IGU, an air flow system in fluid communication with a chamber in the vessel, the air flow system operable to increase or decrease a pressure in the chamber, an exchanger system in communication with the chamber and operable to increase or decrease one or both of a temperature and a humidity level of the chamber, one or more UV bulbs, and a computer system operable to control the air flow system and exchanger system to vary one or more of the following parameters in the chamber: temperature, relative humidity, and pressure.

A quartz glass crucible 1 having a cylindrical side wall portion 10a, a bottom portion 10b, and a corner portion 10c includes a transparent layer 11 as an innermost layer made of quartz glass, a semi-molten layer 13 as an outermost layer made of raw material silica powder solidified in a semi-molten state, and a bubble layer 12 made of quartz glass interposed therebetween. An infrared transmissivity of the corner portion 10c in a state where the semi-molten layer 13 is removed is 25 to 51%, the infrared transmissivity of the corner portion 10c in the state where the semi-molten layer 13 is removed is lower than an infrared transmissivity of the side wall portion 10a, and the infrared transmissivity of the side wall portion 10a in the state where the semi-molten layer 13 is removed is lower than an infrared transmissivity of the bottom portion 10b.

A method for specifying the material of glass or glass ceramic components by either the minimum service life of a component as a function of a predefined mechanical stress or the mechanical resistance as a function of a predefined service life during which mechanical stress occurs. The method enables a leaner dimensioning of mechanically stressed glass and glass ceramic components.

The prism-coupling systems and methods include using a prism-coupling system to collect initial TM and TE mode spectra of a chemically strengthened article having a refractive index profile with a near-surface spike region and a deep region. The initial TM and TE mode spectra are examined to see if they fall within a preferred measurement window that can produce an accurate estimate of the knee stress to within a select tolerance. If not, then measurement configuration of the prism-coupling system is changed and new TM and TE mode spectra are collected. This process is repeated until the new TM and TE mode spectra fall within the preferred measurement window. The new TM and TE mode spectra are then used to determine the knee stress. Changing the measurement configuration can include changing at least one of the measurement wavelength, interfacing fluid thickness and interfacing fluid refractive index.

A system for carrying out gas chromatography/mass spectroscopy (GC/MS) on gasses trapped in glass solidified from molten glass includes a glass sample vacuum chamber having a gas inlet, a gas outlet, and an introduction port for receiving the glass sample; a crushing tool for crushing the glass sample; a gas sample vacuum chamber disposed in downstream fluid communication with the glass sample vacuum chamber; a supply of carrier gas in fluid communication with the glass sample vacuum chamber; a GC/MS analyzer in downstream fluid communication with the gas sample vacuum chamber; an injector in fluid communication between the GC/MS analyzer and the gas sample vacuum chamber and for injecting the gas sample into the GC/MS analyzer; a gather valve in fluid communication between the glass and gas sample vacuum chambers; and a booster in fluid communication with the gas sample vacuum chamber.

Methods of characterizing an optical retardance or a stress-related property of a glass-bases sample include directing a light beam into the glass-based sample while varying the polarization of the light beam to generate scattered light for each polarization are provided. The scattered light for each polarization is captured with an image sensor, which has an exposure time and a frame rate. The scattered light has an intensity distribution at the image sensor. The sample is moved so that the image sensor averages two or more different intensity distributions per frame to form an averaged intensity distribution for each polarization. The averaged intensity distributions for multiple frames are then used to characterize the optical retardance. The optical retardance can turn be used to determine stress-related properties of the glass-based sample. Moving the substrate reduces measurement noise scattered light having no optical retardance information.

The prism-coupling systems and methods include using a prism-coupling system to collect initial TM and TE mode spectra of a chemically strengthened article having a refractive index profile with a near-surface spike region and a deep region. The prism-coupling system has a light source configured to generate sequential measurement light beams or reflected light beams having different measurement wavelengths. The different measurement wavelengths generate different TM and TE mode spectra. The light source can include multiple light-emitting elements and optical filters or a broadband light source and optical filters. The optical filters can be sequentially inserted into either the input optical path or the output optical path of the prism-coupling system.

Methods of characterizing ion-exchanged chemically strengthened Li-containing glasses include: a) measuring a mode spectrum of the glass sample; b) using the mode spectrum, estimating a first contribution to the center tension associated with a spike region and estimating a second contribution to the center tension due to a deep region only, wherein the deep region is assumed to follow a power-law stress profile; and c) determining a total center tension by adding of the first and second contributions to the center tension. The methods can be used for quality control during manufacturing of glass samples by comparing the total center tension to a center tension specification that provides optimum strength and durability.