SENSOR SYSTEM FOR MEASURING BIOPOTENTIALS

摘要

A system (11) for measuring a biopotential signal produced by a body (14) in free space at a location adjacent to the body (14), and if desired, through clothing, includes a probe (12, 112, 212, 312, 412) that can be positioned adjacent to the body (14). The probe (12, 112, 212, 312, 412) includes a conductive electrode (20, 120, 220, 320a, 320b, 420) to receive the biopotential signal and a conductor (24, 124, 224, 324a, 324b, 324c, 424) that is maintained at a fixed distance from the electrode (20, 120, 220, 320a, 320b, 420). The potential of the conductor (24, 124, 224, 324a, 324b, 324c, 424) can be maintained substantially equal to the potential of the electrode (20, 120, 220, 320a, 320b, 420) to shield the electrode (20, 120, 220, 320a, 320b, 420) from stray electrical noise. The system (11) further includes a high impedance first stage amplifier in probe electronics (28, 128, 228, 328, 428) that is incorporated into the probe (12, 112, 212, 312, 412), electrically connected to the electrode (20, 120, 220, 320a, 320b, 420) in a manner to minimize connector noise and functionally compares the electrical potential of the electrode (20, 120, 220, 320a, 320b, 420) to a second potential (e.g. a local ground) and generates a signal that is indicative of the biopotential.