Modeling a Novel Circular Diaphragm Microelectromechanical System for Intraocular Pressure Evaluation

Abstract

This paper presents a new Microelectromechanical capacitive pressure device designed for continuous intraocular pressure (IOP) measurement in glaucoma patients. The device is capable of accurately measuring IOP within the range of 0-8000 Pascal (Pa). A key focus of this research is on reducing the device’s size compared to previous designs, which results in benefits like better energy efficiency, lighter weight, and lower costs. These improvements contribute to more effective glaucoma treatment and enhanced patient care. The device’s design features a circular diaphragm combined with circular spiral meanders, increasing flexibility and reducing stiffness, which improves overall performance. The diaphragm is made of 3.5 μm thick polysilicon, with a radius of 0.1 mm and a 3 μm air gap separating it from the fixed plate. Under pressures up to 8000 Pa, the resonant frequency decreases to 88.243 kHz. The capacitive sensitivity is calculated at 2.6175×10-4 (1/Pa), while the mechanical sensitivity is 0.265 nm/Pa. The performance of the device is thoroughly evaluated through simulations using IntelliSuite software. A comparative analysis shows that this device is smaller and more efficient than previous designs, with dimensions of 200 μm and 100 μm in diameter. This development indicates notable progress in glaucoma treatment and utilizing biological sensing in many applications.