Patents by Inventor Per-Olav Dahlin

Per-Olav Dahlin 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).

  • Automatic darkening filter with offset polarizers
    Patent number: 7884888
    Abstract: A protective automatic darkening filter construction 10 includes two low twist liquid crystal cells 26, 30 interspersed between a series of offset polarizers 24, 28, 32. The resulting construction provides improved homogeneity in the dark state as viewed by the user over a large viewing angle. By reducing variations in shade, visibility through the filter may be improved.
    Type: Grant
    Filed: December 4, 2008
    Date of Patent: February 8, 2011
    Assignee: 3M Innovative Properties Company
    Inventors: Kristina M. Magnusson, Kenneth Jarefors, Per-Olav Dahlin
  • AUTOMATIC DARKENING FILTER WITH OFFSET POLARIZERS
    Publication number: 20090079886
    Abstract: A protective automatic darkening filter construction 10 includes two low twist liquid crystal cells 26, 30 interspersed between a series of offset polarizers 24, 28, 32. The resulting construction provides improved homogeneity in the dark state as viewed by the user over a large viewing angle. By reducing variations in shade, visibility through the filter may be improved.
    Type: Application
    Filed: December 4, 2008
    Publication date: March 26, 2009
    Inventors: Kristina M. Magnusson, Kenneth Jarefors, Per-Olav Dahlin
  • Automatic darkening filter with offset polarizers
    Patent number: 7477330
    Abstract: A protective automatic darkening filter construction 10 includes two low twist liquid crystal cells 26, 30 interspersed between a series of offset polarizers 24, 28, 32. The resulting construction provides improved homogeneity in the dark state as viewed by the user over a large viewing angle. By reducing variations in shade, visibility through the filter may be improved.
    Type: Grant
    Filed: March 9, 2005
    Date of Patent: January 13, 2009
    Assignee: 3M Innovative Properties Company
    Inventors: Kristina M. Magnusson, Kenneth Jarefors, Per-Olav Dahlin
  • Automatic darkening filter with offset polarizers
    Publication number: 20060203148
    Abstract: A protective automatic darkening filter construction 10 includes two low twist liquid crystal cells 26, 30 interspersed between a series of offset polarizers 24, 28, 32. The resulting construction provides improved homogeneity in the dark state as viewed by the user over a large viewing angle. By reducing variations in shade, visibility through the filter may be improved.
    Type: Application
    Filed: March 9, 2005
    Publication date: September 14, 2006
    Inventors: Kristina Magnusson, Kenneth Jarefors, Per-Olav Dahlin