Non-Contact Biopotential Sensor
First Claim
1. A sensor for measuring an electric field, said system comprising:
- a sensing plate capacitively coupled to a body surface, wherein changes in electrical potential at the body surface generates an electric field that induces change in the electric potential of the sensing plate, the sensing plate including a sensing node positioned in the electric field for generating an input signal from the electric field, the sensing plate separated from the body surface by an intervening material;
an amplifier configured to amplify the input signal, the amplifier having an input port and an output port, the amplifier configured to receive the input signal at the input port and to generate an amplified output signal at the output port; and
a switching circuit connected to the input port and a reference voltage, the switching circuit configured to non-continuously close a shunting path from the sensing node to the reference voltage to reset the sensing node connected to the input port.
1 Assignment
0 Petitions
Accused Products
Abstract
A capacitive sensor system including a sensing plate, an amplifier, and a switching circuit is described. The sensing plate is capacitively coupled to a body surface. A change in the electric potential on the body surface generates an electric field that induces change in the electric potential of the sensing plate. The sensing plate includes a sensing node positioned in the electric field for generating an input signal from the electric field. The sensing plate is not in contact with the body surface. The amplifier receives the input signal at the input port, amplifies the input signal and generates an output signal at the output port. The switching circuit is connected to the input port and a reference voltage. The switching circuit non-continuously closes a shunting path from the sensing node to the reference voltage to reset the voltage at the sensing node.
49 Citations
38 Claims
-
1. A sensor for measuring an electric field, said system comprising:
-
a sensing plate capacitively coupled to a body surface, wherein changes in electrical potential at the body surface generates an electric field that induces change in the electric potential of the sensing plate, the sensing plate including a sensing node positioned in the electric field for generating an input signal from the electric field, the sensing plate separated from the body surface by an intervening material; an amplifier configured to amplify the input signal, the amplifier having an input port and an output port, the amplifier configured to receive the input signal at the input port and to generate an amplified output signal at the output port; and a switching circuit connected to the input port and a reference voltage, the switching circuit configured to non-continuously close a shunting path from the sensing node to the reference voltage to reset the sensing node connected to the input port. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31)
-
-
32. A sensor for measuring an electric field, said system comprising:
-
a sensing plate capacitively coupled to a body surface, wherein changes in electric potential on the body surface generates an electric field that induces change in the electric potential of the sensing plate, the sensing plate including a sensing node positioned in the electric field for generating a signal from the electric field, the sensing plate separated from the body surface by an intervening material; an amplifier configured to amplify the input signal, the amplifier having an input port and an output port, the amplifier configured to receive the input signal at the input port and to generate an amplified output signal at the output port; a switching circuit including at least one switching device and a reset circuit including a plurality of capacitors, the plurality of capacitors configured to generate activation voltage to the at least one switching device to turn on or activate the at least one switching device, the switching circuit connected to the input port and a reference voltage, the switching circuit configured to non-continuously close a shunting path from the sensing node to the reference voltage to reset the sensing node connected to the input port when the at least one switching device is turned on; and unity gain amplifier having a first input port and a first output port, the first input port coupled to the input port of the amplifier, the unity gain amplifier configured to generate a first output voltage at the first output port, the unity gain amplifier coupled to one or more resistors, wherein the one or more resistors configured to pull the plurality of capacitors to the first output voltage when the at least one switching device is off. - View Dependent Claims (33, 34, 35, 36, 37, 38)
-
Specification