Method for imaging a medium through electrical measurements with a contact impedance correction

US9933380B2 · kind B2 · utility

Assignees

• COMMISSARIAT A L'ENERGIE ATOMIQUE ET AUX ENERGIES ALTERNATIVES · FR
• Institut National de la Sante et de la Recherche Medicale (INSERM) · FR

Inventors

• Alexandre Fouchard · Grenoble, FR
• Stephane Bonnett · Val-de-Reuil, FR
• Olivier David · Jouy-en-Josas, FR
• Pascale Pham · Crolles, FR

Key dates

• Filing date: Nov 27, 2015
• Grant date: Apr 3, 2018
• Expiry date: Mar 10, 2036

Classification

• Technology area (CPC A): Human Necessities
• CPC primary: A61B2562/04
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

An EIT or differential EIT method in which measurements of voltage differences between electrodes are performed according to a measurement configuration in which at least one of the electrodes injecting a current in the medium being investigated is also used for performing a measurement of the voltage difference. The contact impedances of the different electrodes are measured thanks to a counter-electrode having a contact area with the medium much higher than the contact area of a unit electrode. The measurement of a contact impedance is performed by impedance spectroscopy by comparison with the impedance spectrum of an equivalent circuit. The contact impedances allow voltage drops in the injection electrodes to be calculated the voltage differences between these electrodes and to be corrected. Alternatively, the contact impedances can be used to correct or complete the direct model.