Spiral-Tube Parylene Intraocular Pressure Sensor
This paper presents the first biocompatible, all-mechanical, micromachined pressure sensor with a high-aspect-ratio spiral-tube structure fabricated through a one-layer parylene process. This passive sensor has zero power consumption and indicates the pressure variation by changes of in situ in-plane spiral rotation, which can be gauged externally by a direct and convenient optical observation. A 1 mm-radius device with a 10-turn spiral has demonstrated a 0.22 degree/mmHg sensitivity in liquid. This device is designed for eye implantation and the intraocular spiral rotation can be recorded from outside of the eye. Such a sensing technology is proposed to monitor the intraocular pressure in glaucoma patients.
Additional Information© 2005 IEEE. Date of Current Version: 05 July 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. The authors would also like to thank Mr. Chi-Yuan Shih and Dr. Ellis Meng for valuable discussions, and other Caltech Micromachining Lab members for fabrication assistance.
Published - CHEmems05.pdf