Microfabricated implantable wireless pressure sensor for use in biomedical applications and pressure measurement and sensor implantation methods
First Claim
1. A variable capacitor of a microfabricated implantable pressure sensor, comprising:
- a substrate defining a plurality of channels;
a flexible member having first and second edges on the substrate and a middle portion extending between the first and second edges and raised above the substrate to define a chamber between the substrate and the middle portion; and
a plurality of capacitor elements extending indirectly from the flexible member, the plurality of capacitor elements being movable within respective channels with changes of fluid pressure on an outer surface of the flexible member, capacitance varying with changes in an overlapping area of the plurality of capacitor elements and the substrate, the flexibility of the middle portion varying across a width of the middle portion, wherein non-linear deformation of the middle portion results in movement of the plurality of capacitor elements within respective channels in a direction that is perpendicular to a plane defined by a top surface of the substrate.
2 Assignments
0 Petitions
Accused Products
Abstract
A variable capacitor, a microfabricated implantable pressure sensor including a variable capacitor and an inductor, and related pressure measurement and implantation methods. The inductor may have a fixed or variable inductance. A variable capacitor and pressure sensors include a flexible member that is disposed on a substrate and defines a chamber. Capacitor elements extend indirectly from the flexible member. Sufficient fluidic pressure applied to an exterior surface of the flexible member causes the flexible member to move or deform, thus causing the capacitance and/or inductance to change. Resulting changes in resonant frequency or impedance can be detected to determine pressure, e.g., intraocular pressure.
-
Citations
41 Claims
-
1. A variable capacitor of a microfabricated implantable pressure sensor, comprising:
-
a substrate defining a plurality of channels; a flexible member having first and second edges on the substrate and a middle portion extending between the first and second edges and raised above the substrate to define a chamber between the substrate and the middle portion; and a plurality of capacitor elements extending indirectly from the flexible member, the plurality of capacitor elements being movable within respective channels with changes of fluid pressure on an outer surface of the flexible member, capacitance varying with changes in an overlapping area of the plurality of capacitor elements and the substrate, the flexibility of the middle portion varying across a width of the middle portion, wherein non-linear deformation of the middle portion results in movement of the plurality of capacitor elements within respective channels in a direction that is perpendicular to a plane defined by a top surface of the substrate. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
-
-
10. A microfabricated implantable pressure sensor, comprising:
-
a variable capacitor including a substrate defining a plurality of channels, a flexible member having first and second edges disposed on a substrate and a middle portion extending between the first and second edges, the middle portion being raised above the substrate, a chamber being defined between the substrate and the middle portion, and a plurality of capacitor elements extending indirectly from the flexible member, the plurality of capacitor elements being movable within respective channels with changes of fluid pressure on an outer surface of the flexible member, capacitance varying with changes in an overlapping area of the plurality of capacitor elements and the substrate, the flexibility of the middle portion varying across a width of the middle portion, wherein non-linear deformation of the middle portion results in movement of the plurality of capacitor elements within respective channels in a direction that is perpendicular to a plane defined by a top surface of the substrate; and an inductor electrically connected to the variable capacitor, an electrical circuit including the variable capacitor and the inductor being configured to generate a detectable resonant frequency shift in response to a change of fluid pressure on an outer surface of the flexible member. - View Dependent Claims (11, 12, 13, 14, 15, 16, 17)
-
-
18. A microfabricated implantable pressure sensor, comprising:
-
a substrate defining a plurality of channels; a flexible member disposed on the substrate, a chamber being defined between the substrate and the flexible member; a variable capacitor comprising a plurality of capacitor elements extending indirectly from the flexible member, the plurality of capacitor elements being movable within respective channels with changes of fluid pressure on an outer surface of the flexible member, capacitance varying with changes in an overlapping area of the plurality of capacitor elements and the substrate, the flexibility of a middle portion of the flexible member varying across a width of the middle portion, wherein non-linear deformation of the middle portion results in movement of the plurality of capacitor elements within respective channels in a direction that is perpendicular to a plane defined by a top surface of the substrate; and a variable inductor electrically connected to the variable capacitor, the flexible member carrying components of the variable inductor, the flexible member being movable in response to a fluid pressure change on an outer surface of the flexible member to vary capacitance and inductance. - View Dependent Claims (19, 20, 21)
-
-
22. A variable capacitor of a microfabricated implantable pressure sensor, comprising:
-
a substrate defining a plurality of channels; a flexible member having first and second edges on the substrate and a middle portion extending between the first and second edges and raised above the substrate to define a chamber between the substrate and the middle portion; a plurality of capacitor elements movable within respective channels with changes of fluid pressure on an outer surface of the flexible member, capacitance varying with changes in an overlapping area of the plurality of capacitor elements and the substrate; a cross bar carrying the plurality of capacitor elements; and an intermediate member extending between the flexible member and the cross bar such that the plurality of capacitor elements extend indirectly from the flexible member. - View Dependent Claims (23, 24, 25, 26, 27, 28, 29)
-
-
30. A microfabricated implantable pressure sensor, comprising:
-
a variable capacitor including a substrate defining a plurality of channels, a flexible member having first and second edges disposed on a substrate and a middle portion extending between the first and second edges, the middle portion being raised above the substrate, a chamber being defined between the substrate and the middle portion, a plurality of capacitor elements, a cross bar carrying the plurality of capacitor elements, and an intermediate member extending between the flexible member and the cross bar such that the plurality of capacitor elements extend indirectly from the flexible member, the plurality of capacitor elements being movable within respective channels with changes of fluid pressure on an outer surface of the flexible member, capacitance varying with changes in an overlapping area of the plurality of capacitor elements and the substrate; and an inductor electrically connected to the variable capacitor, an electrical circuit including the variable capacitor and the inductor being configured to generate a detectable resonant frequency shift in response to a change of fluid pressure on an outer surface of the flexible member. - View Dependent Claims (31, 32, 33, 34, 35, 36, 37)
-
-
38. A microfabricated implantable pressure sensor, comprising:
-
a substrate defining a plurality of channels; a flexible member disposed on the substrate, a chamber being defined between the substrate and the flexible member; a variable capacitor comprising a plurality of capacitor elements movable within respective channels with changes of fluid pressure on an outer surface of the flexible member, a cross bar carrying the plurality of capacitor elements, and an intermediate member extending between the flexible member and the cross bar such that the plurality of capacitor elements extend indirectly from the flexible member, capacitance varying with changes in an overlapping area of the plurality of capacitor elements and the substrate; and a variable inductor electrically connected to the variable capacitor, the flexible member carrying components of the variable inductor, the flexible member being movable in response to a fluid pressure change on an outer surface of the flexible member to vary capacitance and inductance. - View Dependent Claims (39, 40, 41)
-
Specification