Planar capacitive sensors – designs and applications

Purpose – The purpose of this paper is to present the sensing mechanism, design issues, performance evaluation and applications for planar capacitive sensors. In the context of characterisation and imaging of a dielectric material under test (MUT), a systematic study of sensor modelling, features and design issues is needed. In addition, the influencing factors on sensitivity distribution, and the effect of conductivity on sensor performance need to be further studied for planar capacitive sensors.Design/methodology/approach – While analytical methods can provide accurate solutions to sensors of simple geometries, numerical modelling is preferred to obtain sensor response to different design parameters and properties of MUT, and to derive the sensitivity distributions of various electrode designs. Several important parameters have been used to evaluate the response of the sensors in different sensing modes. The designs of different planar capacitive sensor arrays are presented and experimentally evaluated...

[1]  Darrell E. Schlicker,et al.  Inductive and capacitive array imaging of buried objects , 2006 .

[2]  Wuqiang Yang,et al.  Hardware design of electrical capacitance tomography systems , 1996 .

[3]  R. Igreja,et al.  Analytical evaluation of the interdigital electrodes capacitance for a multi-layered structure , 2004 .

[4]  Darrell Eugene Schlicker.  Imaging of absolute electrical properties using electroquasistatic and magnetoquasistatic sensor arrays , 2005 .

[5]  Wonchan Kim,et al.  A 600-dpi capacitive fingerprint sensor chip and image-synthesis technique , 1999, IEEE J. Solid State Circuits.

[6]  Ren C. Luo,et al.  Design and implementation of capacitive proximity sensor using microelectromechanical systems technology , 1998, IEEE Trans. Ind. Electron..

[7]  Geoff G. DIAMOND,et al.  A New Capacitive Imaging Technique for NDT , .

[8]  A.V. Mamishev,et al.  Design principles for multichannel fringing electric field sensors , 2006, IEEE Sensors Journal.

[9]  Maurice Beck,et al.  Tomographic imaging of two-component flow using capacitance sensors , 1989 .

[10]  Kishore Sundara-Rajan,et al.  Interdigital sensors and transducers , 2004, Proceedings of the IEEE.

[11]  Jurjen Zoethout,et al.  High Performance Capacitive Position Sensing Device for Compact Active Magnetic Bearing Spindles , 2003 .

[12]  Wuqiang Yang,et al.  New AC-based capacitance tomography system , 1999 .

[13]  Joseph A. Paradiso,et al.  Electric Field Sensing For Graphical Interfaces , 1998, IEEE Computer Graphics and Applications.

[14]  Maurice Beck,et al.  REVIEW ARTICLE: Electronic transducers for industrial measurement of low value capacitances , 1988 .

[15]  Tomasz Dyakowski,et al.  Particle detection using an integrated capacitance sensor , 2001 .

[16]  G. Picotto,et al.  A novel AC current source for capacitance-based displacement measurements , 1996 .

[17]  Yanko Konstantinov Sheiretov,et al.  Deep penetration magnetoquasistatic sensors , 2001 .

[18]  Joshua R. Smith,et al.  FiberFingerprint Identification , 2002 .

[19]  Wuliang Yin,et al.  Optimum design of segmented capacitance sensing array for multi-phase interface measurement , 1996 .

[20]  Tobias Merkel,et al.  Electric fields in fluidic channels and sensor applications with capacitance , 2000 .

[21]  Lihui Peng,et al.  Image reconstruction algorithms for electrical capacitance tomography , 2003 .

[22]  Wuqiang Yang,et al.  An impedance-analyser-based multi-channel imaging system and its applications , 2008, 2008 IEEE International Workshop on Imaging Systems and Techniques.

[23]  Maurice Beck,et al.  Capacitance-based instrumentation for multi-interface level measurement , 1991 .

[24]  Augusto García-Valenzuela,et al.  Isotropic scaling law of the electrical capacitance , 2010 .

[25]  Maurice Beck,et al.  Design of capacitance electrodes for concentration measurement of two-phase flow , 1990 .

[26]  Alexander Mamishev,et al.  Optimization of multi-wavelength interdigital dielectrometry instrumentation and algorithms , 1998 .