Title:
【発明の名称】高感度センサー
Document Type and Number:
Japanese Patent JPH08500431
Kind Code:
A
Abstract:
PCT No. PCT/EP93/00969 Sec. 371 Date Jan. 3, 1995 Sec. 102(e) Date Jan. 3, 1995 PCT Filed Apr. 21, 1993 PCT Pub. No. WO93/22669 PCT Pub. Date Nov. 11, 1993Sensor provided with a thin membrane, capable of storing electrical charges, whose surface is in contact with the chemical, biological, and/or other physical parameters to be measured. The membrane is part of an electromechanical resonance circuit, operating with propagating acoustic waves. Provision is made opposite the membrane for converters, equipped with interdigital structures, to act as transmitter and receiver for the propagating acoustic plate waves. Each of the converters is equipped with interdigital structures that act as narrow band, filters. The transmitter converter and the receiver converter is arranged with a distance between them. The signal from the receiver converter is detected capacitively. A suitable electronic control and evaluation circuit or feedback is provided in addition between the output signal of the receiver converter and the transmitter converter. Finally, a DC voltage is applied between the membrane on the one hand and the transmitter converter and the receiver converter on the other. The voltage has an alternating voltage superimposed on it in the transmitter converter. The generation of the acoustic plate waves in transmitter converter is produced solely on the basis of electrostatic attractive force or excitation between interdigital structures of the transmitter converter and the membrane. The output signal of the receiver converter is additionally decoupled in a capacitive manner in such fashion that the vibration amplitude of the acoustic propagating plate waves is measured in the receiver converter by the capacitor formed by interdigital structures of the receiver converter and the membrane. Finally, the membrane and interdigital structures of the transmitter converter on the transmitter side and the membrane and interdigital structures of the receiver converter on the receiver side are arranged spaced apart from one another by a spatial distance in the form of a gap. They have no mechanically solid connection with one another. A dielectric in the form of a narrow gap is therefore formed such that movement of the membrane toward the interdigital structures is possible in the dielectric.
Inventors:
Guizrel Thomas
Mayer Yacht.-Uwe
Mayer Yacht.-Uwe
Application Number:
JP51888593A
Publication Date:
January 16, 1996
Filing Date:
April 21, 1993
Export Citation:
Assignee:
Fraunhofer-Gesellschaftsza Felderung der Angewanten Vorschunk A. Fao.
International Classes:
G01N29/00; G01N29/02; H04R17/08; (IPC1-7): G01N29/18
Attorney, Agent or Firm:
Masayoshi Misawa