Patents by Inventor Albertus Veld

Albertus Veld 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).

  • Apparatus for selectively measuring ions in a liquid
    Patent number: 4589970
    Abstract: The apparatus (14) is constructed and arranged to measure ions in a liquid (30) and comprises a measuring circuit (10) including an ISFET (16), a reference electrode (32), an amplifier (22) and a protection system (12)/guard circuit (40) connected to the measuring circuit (10). The protection system 12/guard circuit 40 comprises at least one electrode (46 or 47) connected via a low-impedance contact (or ring 62/46 or ring electrode 42) to the liquid (30) and coupled to the ISFET (16) by a protective element (64; 65, 66; or 68 and/or 50; 51, 52; 54; 56; or 58) having a low-impedance for high voltages and a high resistance to low voltages.In one preferred embodiment, the ISFET (16) is provided on a chip (90) and has an electrode (46/62) in as closely spaced relationship as possible to the gate region (34) of the ISFET (16).
    Type: Grant
    Filed: August 16, 1984
    Date of Patent: May 20, 1986
    Assignee: Cordis Europa N.V.
    Inventors: Hendrikus C. G. Ligtenberg, Albertus Veld