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Unpowered spiral-tube parylene pressure sensor for intraocular pressure sensing

Chen, Po-Jui and Rodger, Damien C. and Humayun, Mark S. and Tai, Yu-Chong (2006) Unpowered spiral-tube parylene pressure sensor for intraocular pressure sensing. Sensors and Actuators A: Physical, 127 (2). 276 - 282.

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This paper presents the first biocompatible, unpowered, micromachined pressure sensor for intraocular pressure (IOP) sensing. This device is designed for implantation in the eye so that IOP can be faithfully measured externally. It features a parylene-based high-aspect-ratio spiral-tube structure fabricated using a buried-channel process. This passive sensor requires no power from other physical (i.e. electrical and/or magnetic) domains and registers pressure variations by changes of a mechanical in-plane spiral rotation that can be gauged by direct and convenient optical observation. The fabricated device has been tested in various media, and a 1 mm-radius device with a 10-turn spiral has successfully demonstrated continuous spiral rotation when immersed in liquids, with 0.22°/mmHg sensitivity in isopropyl alcohol (IPA) and 0.13°/mmHg sensitivity in water. This pressure sensing technology is proposed as a convenient method to monitor in situ IOP in glaucoma patients and to facilitate treatment and scientific study of the disease.

Item Type:Article
Additional Information:MEMS 2005 Special Issue - Special Issue of the Micromechanics Section of Sensors and Actuators (SAMM), based on contributions revised from the technical digest of the IEEE 18th International Conference on Micro Electro Mechanical Systems (MEMS-2005).
Uncontrolled Keywords:High aspect-ratio; Intraocular pressure; Parylene; Pressure sensor; Spiral tube
Subjects:Analytical Science > Nanotechnology for sensing and actuating
ID Code:4733
Deposited By:SPI
Deposited On:30 Jun 2009 16:13
Last Modified:30 Jun 2009 16:13

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