Patents by Inventor Rostislav Vatchev Roussev

Rostislav Vatchev Roussev has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 11104608
    Abstract: Ion-exchanged glass ceramic articles described herein have a stress that decreases with increasing distance according to a substantially linear function from a depth of about 0.07 t to a depth of about 0.26 t from the outer surface of the ion-exchanged glass ceramic article from a compressive stress to a tensile stress. The stress transitions from the compressive stress to the tensile stress at a depth of from about 0.18 t to about 0.25 t from the outer surface of the ion-exchanged glass ceramic article. An absolute value of a maximum compressive stress at the outer surface of the ion-exchanged glass article is from 1.8 to 2.2 times an absolute value of a maximum central tension (CT) of the ion-exchanged glass article, and the glass ceramic article has a fracture toughness of 1 MPa?m or more as measured according to the double cantilever beam method.
    Type: Grant
    Filed: November 13, 2019
    Date of Patent: August 31, 2021
    Assignee: Corning Incorporated
    Inventors: Ryan Claude Andrews, Albert Joseph Fahey, Lisa Marie Noni, Rostislav Vatchev Roussev, Charlene Marie Smith, Ljerka Ukrainczyk, Shelby Kerin Wilson
  • Patent number: 11105612
    Abstract: The hybrid measurement system includes an evanescent prism coupling spectroscopy (EPCS) sub-system and a light-scattering polarimetry (LSP) sub-system. The EPCS sub-system includes an EPCS light source optically coupled to an EPCS detector system through an EPCS coupling prism. The LSP sub-system includes an LSP light source optically coupled to an optical compensator, which in turn is optically coupled to a LSP detector system via a LSP coupling prism. A support structure supports the EPCS and LSP coupling prisms to define a coupling prism assembly, which supports the two prisms at a measurement location. Stress measurements made using the EPCS and LSP sub-systems are combined to fully characterize the stress properties of a transparent chemically strengthened substrate. Methods of processing the EPCS and LSP measurements to improve measurement accuracy are also disclosed.
    Type: Grant
    Filed: March 20, 2020
    Date of Patent: August 31, 2021
    Assignee: Corning Incorporated
    Inventors: Ryan Claude Andrews, Pierre Michel Bouzi, William John Furnas, Jeremiah Robert Jacobson, Glenn Abram Newcomer, Evan Lewis Olson, Babak Robert Raj, Rostislav Vatchev Roussev, Viktor Stepanov, Nathaniel David Wetmore
  • Publication number: 20210253473
    Abstract: A non-frangible glass article strengthened by a dual or two-step ion exchange (IOX) process, where the first IOX step leads to a depth of compressive layer FSM_DOL>0.1·t or, in some embodiments, FSM_DOL>0.15·t, where t is the thickness of the glass, is provided. The glass article has a compressive stress CS1 after the first IOX step at the surface of from 100 MPa to 400 MPa or, in some embodiments, from 150 MPa to 300 MPa. The first IOX step is followed by a second IOX step, leading to a “spike” compressive stress CS2 after the second IOX step at the surface of greater than 500 MPa or, in some embodiments, 700 MPa. The width of the spike generated by the second IOX is between 1 ?m and 30 ?m, or between 8 ?m and 15 ?m, using the criteria where the magnitude (absolute value) of the slope of the spike is higher than 20 MPa/?m.
    Type: Application
    Filed: May 3, 2021
    Publication date: August 19, 2021
    Inventors: PASCALE ORAM, Rostislav Vatchev Roussev, Vitor Marino Schneider, Emily Elizabeth Young
  • Patent number: 11084756
    Abstract: Chemically strengthened glass articles having at least one deep compressive layer extending from a surface of the article to a depth of compression DOC of at least about 125 ?m within the glass article. The compressive stress profile includes a single linear segment or portion extending from the surface to the depth of compression DOC. Alternatively, the compressive stress profile may include an additional portion extending from the surface to a relatively shallow depth and the linear portion extending from the shallow depth to the depth of compression.
    Type: Grant
    Filed: March 26, 2020
    Date of Patent: August 10, 2021
    Assignee: Corning Incorporated
    Inventors: Jaymin Amin, Benedict Osobomen Egboiyi, Jonathan David Pesansky, Kevin Barry Reiman, Rostislav Vatchev Roussev, Brian Paul Strines
  • Patent number: 11079280
    Abstract: Apparatus and methods for measuring mode spectra for ion-exchanged glass substrates having a steep index region are disclosed. An interfacing fluid is provided between the coupling prism and the glass substrate. The interfacing fluid thickness is selected so that the variation in modal birefringence with fluid thickness is reduced to an acceptable level. The coupling prism can include a prism coating on the coupling surface so that the substrate-prism interface includes the prism coating. The coupling prism can also include stand-off members that serve to define the thickness of the interfacing fluid.
    Type: Grant
    Filed: May 4, 2018
    Date of Patent: August 3, 2021
    Assignee: CORNING INCORPORATED
    Inventors: Rostislav Vatchev Roussev, Vitor Marino Schneider
  • Patent number: 11053162
    Abstract: A method of reworking lithium containing ion exchanged glass articles is provided. The method includes a reverse ion exchange process that returns the glass article to approximately the composition of the glass from which the glass article was produced, before being subjected to ion exchange. The reworked glass articles exhibit a K2O concentration profile comprising a portion wherein a K2O concentration increases to a local K2O concentration maximum.
    Type: Grant
    Filed: February 2, 2017
    Date of Patent: July 6, 2021
    Assignee: CORNING INCORPORATED
    Inventors: Ryan Claude Andrews, Jill Marie Hall, Pascale Oram, Rostislav Vatchev Roussev, Vitor Marino Schneider, Ljerka Ukrainczyk
  • Publication number: 20210181802
    Abstract: Glass-based articles are provided that exhibit improved drop performance. The relationship between properties attributable to the glass composition and stress profile of the glass-based articles are provided that indicate improved drop performance.
    Type: Application
    Filed: February 19, 2021
    Publication date: June 17, 2021
    Inventors: Emily Marie Aaldenberg, Jared Seaman Aaldenberg, Xiaoju Guo, Peter Joseph Lezzi, Jian Luo, Rostislav Vatchev Roussev
  • Publication number: 20210164959
    Abstract: 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.
    Type: Application
    Filed: February 8, 2021
    Publication date: June 3, 2021
    Inventors: Rostislav Vatchev Roussev, Vitor Marino Schneider
  • Patent number: 11021393
    Abstract: A non-frangible glass article strengthened by a dual or two-step ion exchange (IOX) process, where the first IOX step leads to a depth of compressive layer FSM_DOL>0.1·t or, in some embodiments, FSM_DOL>0.15·t, where t is the thickness of the glass, is provided. The glass article has a compressive stress CS1 after the first IOX step at the surface of from 100 MPa to 400 MPa or, in some embodiments, from 150 MPa to 300 MPa. The first IOX step is followed by a second IOX step, leading to a “spike” compressive stress CS2 after the second IOX step at the surface of greater than 500 MPa or, in some embodiments, 700 MPa. The width of the spike generated by the second IOX is between 1 ?m and 30 ?m, or between 8 ?m and 15 ?m, using the criteria where the magnitude (absolute value) of the slope of the spike is higher than 20 MPa/?m.
    Type: Grant
    Filed: March 8, 2019
    Date of Patent: June 1, 2021
    Assignee: Corning Incorporated
    Inventors: Pascale Oram, Rostislav Vatchev Roussev, Vitor Marino Schneider, Emily Elizabeth Young
  • Publication number: 20210155533
    Abstract: Glass-based articles comprise stress profiles providing improved fracture resistance and decreased weight gain. The glass-based articles are produced with a single-step ion exchange process.
    Type: Application
    Filed: November 20, 2020
    Publication date: May 27, 2021
    Inventors: Pascale Oram, Rostislav Vatchev Roussev
  • Publication number: 20210155532
    Abstract: A glass composition includes from 55.0 mol % to 75.0 mol % SiO2; from 8.0 mol % to 20.0 mol % Al2O3; from 3.0 mol % to 15.0 mol % Li2O; from 5.0 mol % to 15.0 mol % Na2O; and less than or equal to 1.5 mol % K2O. The glass composition has the following relationships: Al2O3+Li2O is greater than 22.5 mol %, R2O+RO is greater than or equal to 18.0 mol %, R2O/Al2O3 is greater than or equal to 1.06, SiO2+Al2O3+B2O3+P2O5 is greater than or equal to 78.0 mol %, and (SiO2+Al2O3+B2O3+P2O5)/Li2O is greater than or equal to 8.0. The glass composition may be used in a glass article or a consumer electronic product.
    Type: Application
    Filed: February 1, 2021
    Publication date: May 27, 2021
    Inventors: Timothy Michael Gross, Xiaoju Guo, Peter Joseph Lezzi, Alexandra Lai Ching Kao Andrews Mitchell, Rostislav Vatchev Roussev
  • Publication number: 20210140836
    Abstract: Methods of improving the measurement of knee stress in an ion-exchanged chemically strengthened Li-containing glass sample that includes a knee are disclosed. One of the methods includes compensating for a shift in the location of the TIR-PR transition location associated with the critical angle location, wherein the shift is due to the presence of a leaky mode. Another method includes applying select criteria to the captured mode spectra image to ensure a high-quality image is used for the knee stress calculation. Another method combines direct and indirect measurements of the knee stress using the mode spectra from multiple samples to obtain greater accuracy and precision as compared to using either the direct measurement method or the indirect measurement method alone. Quality control methods of forming the glass samples using measured mode spectra and related techniques for ensuring an accurate measurement of the knee stress are also disclosed.
    Type: Application
    Filed: January 25, 2021
    Publication date: May 13, 2021
    Inventors: Ryan Claude Andrews, Rostislav Vatchev Roussev, Vitor Marino Schneider
  • Publication number: 20210131959
    Abstract: The prism-coupling systems and methods include using a prism-coupling system to collect a 2D digital mode spectrum of an IOX article. The mode line and critical angle positions and orientations are found by performing a weighted fit to mode line and critical angle images and are used to define a compensated mode spectrum. If mode line tilt is found, it is removed from the 2D digital mode spectrum to define the compensated mode spectrum. The compensated mode spectrum is then processed using techniques known in the art to provide a more accurate estimate of stress-related characteristics of the IOX sample versus using the uncompensated mode spectrum. Derivative-based methods of accurately establishing positions of intensity transitions in a mode spectrum of an IOX sample using a derivative spectrum and curve fitting are also disclosed.
    Type: Application
    Filed: October 30, 2020
    Publication date: May 6, 2021
    Inventors: Ryan Claude Andrews, Rostislav Vatchev Roussev, Antons Treikalis, Ming Yang
  • Patent number: 10934208
    Abstract: A strengthened article (and methods for making it) is provided that includes a glass, glass-ceramic or ceramic, having a plurality of primary surfaces, side edges, and a thickness. The article also includes a compressive stress region extending from one of the primary surfaces to a first selected depth in the article; a central region extending from a boundary located at a depth of 200 ?m from the primary surfaces and the edges to the centroid of the article; and an outer region extending between the primary surfaces and edges to the boundary. Further, the maximum principal stress within the outer region is no more than two times the maximum principal stress within the central region. The primary surfaces and side edges may define a plurality of corners, and the corners may be defined by a chamfer, a fillet, or a curved shape.
    Type: Grant
    Filed: April 21, 2016
    Date of Patent: March 2, 2021
    Assignee: CORNING INCORPORATED
    Inventors: Izhar Zahoor Ahmed, Guangli Hu, Rostislav Vatchev Roussev, Po-Jen Shih, Irene Marjorie Slater, Vijay Subramanian, Bin Zhang, Sam Samer Zoubi
  • Patent number: 10914721
    Abstract: 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.
    Type: Grant
    Filed: January 14, 2019
    Date of Patent: February 9, 2021
    Assignee: CORNING INCORPORATED
    Inventors: Rostislav Vatchev Roussev, Vitor Marino Schneider
  • Patent number: 10906834
    Abstract: A glass composition includes from 55.0 mol % to 75.0 mol % SiO2; from 8.0 mol % to 20.0 mol % Al2O3; from 3.0 mol % to 15.0 mol % Li2O; from 5.0 mol % to 15.0 mol % Na2O; and less than or equal to 1.5 mol % K2O. The glass composition has the following relationships: Al2O3+Li2O is greater than 22.5 mol %, R2O+RO is greater than or equal to 18.0 mol %, R2O/Al2O3 is greater than or equal to 1.06, SiO2+Al2O3+B2O3+P2O5 is greater than or equal to 78.0 mol %, and (SiO2+Al2O3+B2O3+P2O5)/Li2O is greater than or equal to 8.0. The glass composition may be used in a glass article or a consumer electronic product.
    Type: Grant
    Filed: November 28, 2018
    Date of Patent: February 2, 2021
    Assignee: CORNING INCORPORATED
    Inventors: Timothy Michael Gross, Xiaoju Guo, Peter Joseph Lezzi, Alexandra Lai Ching Kao Andrews Mitchell, Rostislav Vatchev Roussev
  • Patent number: 10900850
    Abstract: Methods of improving the measurement of knee stress in an ion-exchanged chemically strengthened Li-containing glass sample that includes a knee are disclosed. One of the methods includes compensating for a shift in the location of the TIR-PR transition location associated with the critical angle location, wherein the shift is due to the presence of a leaky mode. Another method includes applying select criteria to the captured mode spectra image to ensure a high-quality image is used for the knee stress calculation. Another method combines direct and indirect measurements of the knee stress using the mode spectra from multiple samples to obtain greater accuracy and precision as compared to using either the direct measurement method or the indirect measurement method alone. Quality control methods of forming the glass samples using measured mode spectra and related techniques for ensuring an accurate measurement of the knee stress are also disclosed.
    Type: Grant
    Filed: June 22, 2018
    Date of Patent: January 26, 2021
    Assignee: CORNING INCORPORATED
    Inventors: Ryan Claude Andrews, Rostislav Vatchev Roussev, Vitor Marino Schneider
  • Publication number: 20210017072
    Abstract: A glass-based article including a first surface and a second surface opposing the first surface defining a thickness (t) of about 3 millimeters or less (e.g., about 1 millimeter or less), and a stress profile, wherein all points of the stress profile between a thickness range from about 0·t up to 0.3·t and from greater than about 0.7·t to t, comprise a tangent with a slope having an absolute value greater than about 0.1 MPa/micrometer. In some embodiments, the glass-based article includes a non-zero metal oxide concentration that varies along at least a portion of the thickness (e.g., 0·t to about 0.3·t) and a maximum central tension of less than about 71.5/?(t) (MPa). In some embodiments, the concentration of metal oxide or alkali metal oxide decreases from the first surface to a point between the first surface and the second surface and increases from the point to the second surface. The concentration of the metal oxide may be about 0.05 mol % or greater or about 0.
    Type: Application
    Filed: September 28, 2020
    Publication date: January 21, 2021
    Inventors: Timothy Michael Gross, Guangli Hu, Rostislav Vatchev Roussev, Charlene Marie Smith, Zhongzhi Tang, Steven Alvin Tietje
  • Publication number: 20200400613
    Abstract: Methods of characterizing ion-exchanged chemically strengthened glass containing lithium are disclosed. The methods allow for performing quality control of the stress profile in chemically strengthened Li-containing glasses having a surface stress spike produced in a potassium-containing salt, especially in a salt having both potassium and sodium. The method allows the measurement of the surface compression and the depth of the spike, and its contribution to the center tension, as well as the compression at the bottom of the spike, and the total center tension and calculation of the stress at the knee where the spike and the deep region of the stress profile intersect. The measurements are for a commercially important profile that is near-parabolic in shape in most of the interior of the substrate apart from the spike.
    Type: Application
    Filed: September 3, 2020
    Publication date: December 24, 2020
    Inventors: Ryan Claude Andrews, Rostislav Vatchev Roussev, Vitor Marino Schneider
  • Publication number: 20200333200
    Abstract: 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.
    Type: Application
    Filed: July 6, 2020
    Publication date: October 22, 2020
    Inventors: Ryan Claude Andrews, Chai Hsin Kuang, Rostislav Vatchev Roussev