Patents by Inventor Ralf Takke

Ralf Takke 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: 7981824
    Abstract: The present invention relates to a quartz glass blank for an optical component for transmitting radiation of a wavelength of 15 nm and shorter, the blank consisting of highly pure quartz glass, doped with titanium and/or fluorine, which is distinguished by an extremely high homogeneity. The homogeneity relates to the following features: a) micro-inhomogeneities caused by a local variance of the TiO2 distribution (<0.05% TiO2, averaged over a volume element of (5 ?m)3 in relation to the mean value of the TiO2 content), b) an absolute maximum inhomogeneity in the thermal expansion coefficient ?? in the main functional direction (<5 ppb/K), c) a radial variance of the thermal expansion coefficient over the usable surface of the quartz glass blank of not more than 0.4 ppb/(K.cm); d) a maximum stress birefringence (SDB) at 633 nm in the main functional direction of 2 nm/cm with a specific progression; and e) a specific progression of the ??, averaged according to (b) on the optical surface.
    Type: Grant
    Filed: May 11, 2005
    Date of Patent: July 19, 2011
    Assignee: Heraeus Quarzglas GmbH & Co. KG
    Inventors: Wolfgang Englisch, Ralf Takke, Bodo Kuehn, Bruno Uebbing, Rainer Koeppler
  • Publication number: 20080274869
    Abstract: The present invention relates to a quartz glass blank for an optical component for transmitting radiation of a wavelength of 15 nm and shorter, the blank consisting of highly pure quartz glass, doped with titanium and/or fluorine, which is distinguished by an extremely high homogeneity. The homogeneity relates to the following features: a) micro-inhomogeneities caused by a local variance of the TiO2 distribution (<0.05% TiO2, averaged over a volume element of (5 ?m)3 in relation to the mean value of the TiO2 content), b) an absolute maximum inhomogeneity in the thermal expansion coefficient ?? in the main functional direction (<5 ppb/K), c) a radial variance of the thermal expansion coefficient over the usable surface of the quartz glass blank of not more than 0.4 ppb/(K·cm); d) a maximum stress birefringence (SDB) at 633 nm in the main functional direction of 2 nm/cm with a specific progression; and e) a specific progression of the ??, averaged according to (b) on the optical surface.
    Type: Application
    Filed: May 11, 2005
    Publication date: November 6, 2008
    Applicant: Heraeus Quarzglas GmbH & Co. KG
    Inventors: Wolfgang Englisch, Ralf Takke, Bodo Kuehn, Bruno Uebbing, Rainer Koeppler
  • Patent number: 5410428
    Abstract: This invention relates to an optical member made of highly transparent, high-purity synthetic silica glass, to a method for manufacturing a blank or an optical member of such glass, and to the optical members themselves. The optical members have an absolute refractive index, n.sub.d, of 1.460 or more and a hydrogen molecule concentration of at least 5.times.10.sup.16 molecules/cm.sup.3 uniformly distributed throughout the glass and are particularly well suited for use in apparatus in which they are exposed to a high-power laser beam such as that produced by an excimer laser.
    Type: Grant
    Filed: October 23, 1991
    Date of Patent: April 25, 1995
    Assignees: Shin-Etsu Quartz Products Co. Ltd., Heraeus Quarzglas GmbH
    Inventors: Shigeru Yamagata, Michiyou Kuriyama, Kyoichi Inaki, Ralf Takke
  • Patent number: 5325230
    Abstract: The invention relates to lenses, prisms or other optical members which are subjected to high-power ultraviolet light having a wavelength of about 360 nm or less, or ionizing radiation, particularly optical members for use in laser exposure apparatus for lithography, and to blanks for such optical members. The homogeneity of the refractive index distribution and the resistance to optical deterioration when the optical members are exposed for a long period of time to short wavelength ultraviolet light from a laser beam are improved. The optical members are made of high-purity synthetic silica glass material containing at least about 50 wt. ppm of OH groups, and are doped with hydrogen.
    Type: Grant
    Filed: December 6, 1991
    Date of Patent: June 28, 1994
    Assignees: Shin-Etsu Quartz Products Co., Ltd., Heraeus Quarzglas GmbH
    Inventors: Shigeru Yamagata, Kyoichi Inaki, Toshikatu Matsuya, Ralf Takke, Stephan Thomas, Heinz Fabian
  • Patent number: 5086352
    Abstract: The invention relates to lenses, prisms or other optical members which are subjected to high-power ultraviolet light having a wavelength of about 360 nm or less, or ionizing radiation, particularly optical members for use in laser exposure apparatus for lithography, and to blanks for such optical members. The homogeneity of the refractive index distribution and the resistance to optical deterioration when the optical members are exposed for a long period of time to short wavelength ultraviolet light from a laser beam are improved. The optical members are made of high-purity synthetic silica glass material containing at least about 50 wt. ppm of OH groups, and are doped with hydrogen.
    Type: Grant
    Filed: June 8, 1990
    Date of Patent: February 4, 1992
    Assignees: Shin-Etsu Quartz Products Co., Ltd., Heraeus Quarzglas GmbH
    Inventors: Shigeru Yamagata, Kyoichi Inaki, Toshikatu Matsuya, Ralf Takke, Stephan Thomas, Heinz Fabian
  • Patent number: 4676814
    Abstract: Disclosed is a method for the axial building up, in a vertical arrangement, of a hollow cylindrical soot body having no internal support and consisting substantially of silicon dioxide by means of at least one flame hydrolysis build-up burner serving for the soot production. In this method the soot is deposited at the beginning of the build-up onto an auxiliary body, and during the build-up the build-up burner and the growing soot body are rotated relative to one another, and the burner is at the same time held at an unvarying distance from the growing end of the hollow cylinder and centrally above the predetermined cross section of the upwardly growing end of the cylinder wall. The penetration of soot into the interior of the cylinder is prevented by means of a directed gas stream.
    Type: Grant
    Filed: May 21, 1986
    Date of Patent: June 30, 1987
    Assignee: Heraeus Quarzschmelze GmbH
    Inventors: Dieter Ross, Hans-Ulrich Bonewitz, Uwe Christiansen, Karl-Friedrich Klein, Albert Muhlich, Karlheinz Rau, Wolfgang Ruffing, Fritz Simmat, Anton Steinkohl, Ralf Takke