Patents by Inventor Robert J. C. E. Demandt

Robert J. C. E. Demandt 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).

  • Organic electroluminescent device
    Patent number: 6503644
    Abstract: An organic electroluminescent device whose electroluminescence efficiency is independent of the work function of the cathode material, and whose service life under ambient conditions is excellent without the necessity of taking additional protective measures. These properties are obtained as a result of the fact that an organic layer of the device comprises mobile ions which are compensated by immobile ions in such a manner that the polarity of all mobile ions is the same.
    Type: Grant
    Filed: October 9, 2001
    Date of Patent: January 7, 2003
    Assignee: Koninklijke Philips Electronics N.V.
    Inventors: Hermannus F. M. Schoo, Robert J. C. E. Demandt, Jeroen J. M. Vleggaar, Coen T. H. F. Liedenbaum
  • Organic electroluminescent device
    Patent number: 6326091
    Abstract: An organic electroluminescent device whose electroluminescence efficiency is independent of the work function of the cathode material, and whose service life under ambient conditions is excellent without the necessity of taking additional protective measures. These properties are obtained as a result of the fact that an organic layer of the device comprises mobile ions which are compensated by immobile ions in such a manner than the polarity of all mobile ions is the same.
    Type: Grant
    Filed: April 24, 1997
    Date of Patent: December 4, 2001
    Assignee: U. S. Philips Corporation
    Inventors: Hermannus F. M. Schoo, Robert J. C. E. Demandt, Jeroen J. M. Vleggaar, Coen T. H. F. Liedenbaum
  • Organic electroluminescent device
    Patent number: 6099980
    Abstract: An organic electroluminescent device and a method of manufacturing such a device. By patterned exposure of an alkylatable-compound-containing organic layer of the device to an alkylating agent, a device is obtained which, in operation, exhibits patterned light emission, without it being necessary to structure the electrode layers. A salt is locally formed by means of alkylating in accordance with a pattern. If the salt contains ions which can move under the influence of an electric field, the threshold voltage necessary to produce light emission is reduced.
    Type: Grant
    Filed: July 15, 1997
    Date of Patent: August 8, 2000
    Assignee: U.S. Philips Corporation
    Inventors: Hermannus F. M. Schoo, Robert J. C. E. Demandt
  • Electroluminescent device
    Patent number: 5902689
    Abstract: A description is given of a method of providing an electroluminescent device (20) comprising an active layer (5) of conjugated 2,5-alkyl- or alkoxy-substituted poly(p-phenylene vinylene) with inactive regions (51) and emissive regions (52) by means of patterned irradiation with UV light. Both regions (51) and (52) of the active layer (5) show a clear difference in electroluminescence, electrical resistance and solubility. By means of the above-described effects, displays can be manufactured without making use of structured electrode layers (3) and (11).
    Type: Grant
    Filed: August 1, 1996
    Date of Patent: May 11, 1999
    Assignee: U.S. Philips Corporation
    Inventors: Jeroen J. M. Vleggaar, Adrianus J. M. Berntsen, Aemilianus G. J. Staring, Robert J. C. E. Demandt, Hermanus F. M. Schoo, Coen T. H. F. Liedenbaum
  • CVD method of providing a film of conjugated, substituted or unsubstituted poly(p-phenylene vinylene) on a substrate
    Patent number: 5670212
    Abstract: A conjugated poly(p-phenylene vinylene) is manufactured by means of CVD and using simple monomers. Such a polymer is particularly adaptable for use as an active layer in electroluminescent devices, such as a light-emitting diode.
    Type: Grant
    Filed: May 17, 1995
    Date of Patent: September 23, 1997
    Assignee: U.S. Philips Corporation
    Inventors: Aemilianus G. J. Staring, Dirk J. Broer, Robert J. C. E. Demandt