Patents by Inventor Gustaaf R. Mohlmann

Gustaaf R. Mohlmann 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).

  • Polymeric optical amplifier doped with lanthanide
    Patent number: 5581398
    Abstract: The invention relates to a polymeric optical amplifier doped with lanthanide ions, which are present in the amplifier in the form of a complex. The invention also relates to novel electrically neutral lanthanide complexes which can be applied with advantage in the above-described polymeric optical amplifiers. These complexes comprise host molecules which readily complex with the lanthanide and fully encapsulate it.
    Type: Grant
    Filed: August 19, 1994
    Date of Patent: December 3, 1996
    Assignee: Akzo Nobel NV
    Inventors: Franciscus C. J. M. van Veggel, Gustaaf R. Mohlmann
  • Retardation layer having thin glass substrates
    Patent number: 5576077
    Abstract: The present invention is in the field of retardation layers for liquid crystalline displays, more particularly in the field of retardation layers based on super-twisted nematic (STN) liquid crystalline layer. In the retardation layers of the present invention the liquid crystalline polymer is placed between glass substrates wherein at least one substrate has a thickness of 20-500 micrometers. The use of such thin glass substrates reduces the weight and thickness of the retardation layer.The LC polymer film may also be placed between the substrate of the display cell and a thin glass substrate or between the polarizer and a thin glass substrate. In these embodiments of the invention a second thin glass substrate is not necessary and the thickness and weight of the retardation layer is further reduced.
    Type: Grant
    Filed: September 26, 1994
    Date of Patent: November 19, 1996
    Assignee: Akzo Nobel N.V.
    Inventors: Martin Bosma, Jan W. Venema, Stephen J. Picken, Gustaaf R. Mohlmann
  • Twisted nematic film, a method for the preparation thereof, and a display device comprising said film
    Patent number: 5382648
    Abstract: The invention relates to a twisted nematic film comprising a non-crosslinked liquid-crystalline polymer having a Tg above 75.degree. C. and a rotational viscosity (.gamma.) of less than 5000 Pascal.seconds (Pa.s) between Tg and Tni. Such twisted nematic films are used in displays. The invention further relates to methods for the preparation of these twisted nematic films, to the use of said twisted nematic films for optical data storage and in writable compact disks and to a display device comprising such a twisted film.
    Type: Grant
    Filed: April 1, 1993
    Date of Patent: January 17, 1995
    Assignee: Akzo Nobel nv
    Inventors: Stephen J. Picken, Gustaaf R. Mohlmann
  • Method of making a frequency doubling structure in an optically non-linear medium
    Patent number: 5289308
    Abstract: In an optically non-linear (NLO) polymeric material a frequency doubling structure composed of alternatingly poled NLO polymer is made. This structure can be made by forming a layer of NLO polymer, effecting poling in it with the use of an electric field, partially removing the layer of NLO polymer by etching, such that in the polymer a grating structure is formed composed of etched grooves and projecting polymer parts, the width of the grooves matching that of the polymer parts, dividing the polymer layer containing the grating structure into at least two sections, and placing the two sections one on top of the other, such that grooves of the one section are back-filled by projecting polymer parts of the other section. To prevent the enclosure of air a filler may be added, preferably in the form of a solution of the NLO polymer.
    Type: Grant
    Filed: December 11, 1992
    Date of Patent: February 22, 1994
    Assignee: Akzo N.V.
    Inventors: Winfried H. G. Horsthuis, Gustaaf R. Mohlmann