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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, 127 (2). pp. 276-282. ISSN 0924-4247.

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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
Related URLs:
URLURL TypeDescription DOIArticle
Rodger, Damien C.0000-0002-1583-5946
Humayun, Mark S.0000-0002-5830-5208
Tai, Yu-Chong0000-0001-8529-106X
Additional Information:© 2005 Elsevier. Received 1 March 2005; revised 22 August 2005; accepted 25 August 2005. Available online 27 September 2005. This work was supported in part by the Engineering Research Centers Program of the National Science Foundation under NSF Award Number EEC-0310723 and by a fellowship from the Whitaker Foundation (D.R.). The authors would like to especially thank Dr. Ellis Meng and Mr. Chi-Yuan Shih for their valuable comments, as well as Mr. Trevor Roper and other members of the Caltech Micromachining Laboratory for their fabrication assistance.
Funding AgencyGrant Number
Whitaker FoundationUNSPECIFIED
Subject Keywords:high aspect-ratio; intraocular pressure; parylene; pressure sensor; spiral tube
Issue or Number:2
Record Number:CaltechAUTHORS:20110120-133620929
Persistent URL:
Official Citation:Po-Jui Chen, Damien C. Rodger, Mark S. Humayun, Yu-Chong Tai, Unpowered spiral-tube parylene pressure sensor for intraocular pressure sensing, Sensors and Actuators A: Physical, Volume 127, Issue 2, 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)., 13 March 2006, Pages 276-282, ISSN 0924-4247, DOI: 10.1016/j.sna.2005.08.027.
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:21834
Deposited By: Tony Diaz
Deposited On:26 Jan 2011 17:35
Last Modified:09 Mar 2020 13:19

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