High resolution solid state pressure sensor

摘要

A pressure sensor and pressure-sensing catheter in which a deformable pressure sensing membrane is separated from an inner metalized surface on a rigid support by an air gap. An input allows a voltage to be applied to an electrode on the sensing membrane and an output allows reading of the signal modulation from the support surface. An outer sleeve overlays the membrane and a wire bus transmits the signals to a terminal connector. The catheter may include a vented air gap, a multiplexing wire bus, and an internal cable to maintain tension.

主权项

1. A pressure sensing catheter comprising:
a plurality of pressure sensors, each comprising:
a rigid inner tubular member having an electrically conductive layer defining an inner tubular electrode, the rigid inner tubular member further comprising a first annular raised structure and a second annular raised structure; anda deformable, outer tubular membrane comprising an electrically conductive layer formed on a dielectric polymer and defining an outer tubular electrode, the outer tubular electrode being attached to the first annular raised structure and the second annular raised structure such that the outer tubular electrode is spaced from the inner tubular electrode by an annular gap, said pressure sensors being disposed along the catheter, wherein each pressure sensor is configured to produce an electrical signal varying in response to the capacitance between the outer tubular electrode and the inner tubular electrode such that the electrical signal is representative of a circumferential pressure that is radially acting and distributed along a circumference of the sensor applied to the catheter tube at a location along the catheter; flexible material between pressure sensors of the plurality of pressure sensors; and a signal bus extending through the inner tubular member of each of the plurality of sensors and electrically connected to the electrically conductive layer of each outer tubular membrane and the inner tubular electrode of each pressure sensor, said signal bus extending to terminal connectors at a terminal end of said catheter, said terminal connectors configured to allow access to signals from said pressure sensors whereby a change in capacitance between the inner tubular electrode and the outer tubular electrode may be sensed.