Date of Award
Doctor of Philosophy
Electrical and Computer Engineering
Robert J. Weber
This work describes a miniaturized implantable passive pressure sensor and a remote sensing technique for pressure measurement. The sensor device consists of a capacitor array and a coil inductor, which form a high-Q LC type resonator. The capacitor array, which is also membrane structures, is fabricated by surface micromachining technique. The deflection of the membrane depends on the pressure applied to it. The higher the pressure, the larger the deflection, and the larger the capacitor is. This change of the capacitance will also change the resonant frequency of the LC resonator, and it can be detected by various types of coil detectors. One detecting prototype using a secondary resonator is proposed in this work, the sensing distance can be improved to about 1.5cm, which is larger than most of the publication work in this area. This large sensing distance will allow the detector to be integrated into a spectacles frame. It has more accurate results than prior works. The sensor itself can be smaller than 1.5mmx1.5mmx1mm, and after biocompatible material coating, the sensor can be implanted into the human body. This sensor was particularly designed for intraocular pressure (IOP) measurement. It can provide multiple and continuous IOP readouts under everyday conditions, which is desired to monitor any fluctuations of IOP, and it is very useful for glaucoma diagnosis. The sensor can also be implanted into any other part of human body to remotely measure any pressure of a tissue or inside a chamber, e.g. the pulmonary artery.
Cao, Haibo, "Intraocular pressure (IOP) passive sensor modeling, design, fabrication and measurement" (2008). Graduate Theses and Dissertations. 10899.