Evaluating object and region of concentric electrode in bio-electrical impedance measurement

Concentric electrode is easy to use and used widely for measuring bio-electrical impedance. But, its evaluating region was not investigated in detail. Then, the characteristics of concentric electrode were studied from various points of view. In case of use without electrode paste, impedance is determined with the contacting condition between electrode and skin surface over all frequency range. In case of use with electrode past, impedance is composed of stratum corneum in the frequency range of 20 Hz-1 kHz and is mainly composed of subcutaneous tissue in the range of 200 kHz-1 MHz. In the high frequency range, evaluating region of concentric electrode is the area less than the radius or the gap of center electrode.

I. Introduction

The method measuring bio-electrical impedance using concentric electrode in local part non-invasively is widely applied. Although detecting bio-impedance varies by electrode size, frequency, and types of electrode paste, the detail results have not been cleared yet. Then these points were investigated through some experiments such as adhesive tape stripping. This paper shows some concrete yardsticks as evaluating object and region based on the results.