High-Accuracy Film-Integrated Optical Sensor for Real-Time Intraocular Pressure Monitoring

Intraocular pressure (IOP) is a key indicator to evaluate the risk and status of glaucoma, which is one of the main causes of irreversible blindness. However, the IOP value is susceptible to circadian changes and is difficult to be measured real-time. In this paper, we designed a thin-film integrated optical IOP sensor based on the interferometry principle, which could read out the IOP value by interference patterns and monitor the value changes real-time at the same time. The theoretical and experimental results indicated that our sensor exhibited a sensitivity of 0.19 μm/mmHg and an average accuracy of 0.84 mmHg over the pressure range of 0-45 mmHg, which is comparable with the other reported optical systems but with the advantage of easier fabrication process and low-cost. Our sensor device implies great potential in the application of human physiological index measurement and other chip-integrated medical sensing instruments.