Patents by Inventor Willebrordus Hubertus Martinus Maria VAN DE Spijker

Willebrordus Hubertus Martinus Maria VAN DE Spijker 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).

  • Beryllium-containing europium activated phosphate phosphor, luminescent screen and discharge lamp containing same
    Patent number: 4049992
    Abstract: A luminescent beryllium-containing phosphate activated by bivalent europium defined by the formula Me.sub.a-x Be.sub.b Eu.sub.x P.sub.2 O.sub.8 where a + b = 3 and 0.01.ltoreq.x.ltoreq.0.25 and b has the value 1 or 2. If b = 2, Me mainly represents one of the alkaline earth metals barium, strontium and calcium. If b = 1, Me mainly represents barium and/or strontium.The luminescent phosphate may be used in mercury vapor discharge lamps and in low-pressure cadmium vapor discharge lamps.
    Type: Grant
    Filed: May 22, 1974
    Date of Patent: September 20, 1977
    Assignee: U.S. Philips Corporation
    Inventors: Judicus Marinus Pieter Jan Verstegen, Willebrordus Hubertus Martinus Maria VAN DE Spijker, Emiel Petrus Juliaan DE Meester
  • Luminescent screen with thallium activated aluminate
    Patent number: 3956663
    Abstract: A luminescent screen, particularly for a low-pressure mercury vapor discharge lamp, provided with a luminescent thallium-activated aluminate having the .beta.-alumina structure and defined by the formula (Me.sup.I.sub.1.sub.-x.sub.-p Tl.sub.x Me.sup.II.sub.p) (Al.sub.11.sub.-y Mn.sub.y)O.sub.17 in which Me.sup.I represents at least one of the alkali metals sodium, potassium and rubidium, and in which Me.sup.II represents at least one of the alkaline earth metals calcium, strontium and barium, in which up to 50 mol % of aluminum may be replaced by gallium, and in which0.1.ltoreq.x.ltoreq.0.90.ltoreq.y.ltoreq.0.50.ltoreq.p.ltoreq.0.5x+p.ltoreq.1.
    Type: Grant
    Filed: January 6, 1975
    Date of Patent: May 11, 1976
    Assignee: U.S. Philips Corporation
    Inventors: Judicus Marinus Pieter Jan Verstegen, Willebrordus Hubertus Martinus Maria VAN DE Spijker, Cornelis Wilhelmus Anthonius Schetters