Patents by Inventor Andrea Wickardt

Andrea Wickardt 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).

  • Optical crown glass having negative anomalous partial dispersion and high UV transmission
    Patent number: 5340778
    Abstract: An optical crown glass having a negative anomalous partial dispersion .DELTA.P.sub.g,F, a refractive index n.sub.d of greater than 1.52, an Abbe number .nu..sub.d of greater than 57, and a high UV transmission has a composition (in % by weight) 40-72 B.sub.2 O.sub.3, 9-31 Al.sub.2 O.sub.3, 0-15 SiO.sub.2, 0.1-0.5 H.sub.2 O, 0-12 Li.sub.2 O, wherein the total of R.sub.2 O (R=Li, Na, K, Rb, Cs) is 0-20 and the total of MO (M=Mg, Ca, Sr, Ba) is 0-30, and wherein the total of R.sub.2 O and MO is greater than 5, and the molar ratio between Al.sub.2 O.sub.3 and B.sub.2 O.sub.3 is 0.2-0.3 and the molar ratio between (R.sub.2 O+MO) and B.sub.2 O.sub.3 is 0.1-0.4.
    Type: Grant
    Filed: June 4, 1993
    Date of Patent: August 23, 1994
    Assignee: Scott Glaswerke
    Inventors: Thomas Kloss, Elfi Stein, Kirsten Gerth, Andrea Wickardt