Dry contact less surface electrodes for bioelectrical measurements

This paper describes design and testing of bioelectrical measurement by capacity electrodes. The advantage of this measurement type lies in an indirect-contact between the electrode surface and skin and movement artifact protection. The measurement is easier and more comfortable since capacitively coupled electrodes eliminate the need for conductive gel and direct skin contact with the electrodes. The indirect-contact measurement is also suitable for long-term measurements, where in conductive gel desiccation resulted in loss of contact between the electrode and skin. There is also discussed the electrical design of the indirect-contact ECG prototype mentioned above and the accompanying electrodes along with practical measurements in sittinand lying position with various artifact types. This article serves as a preliminary study of indirect-contact ECG with future intention to implement this system within textile products for sophisticated, comfortable and non-obtrusive ECG measurements.