A Wireless Flexible Electrooculogram Monitoring System With Printed Electrodes

Electroocugraphy (EOG) is a popular method of measuring biopotentials developed across the eyes during eye activities such as eye-blinking, vertical, and horizontal eye-movements. The measured signal is called electrooculogram (EOG) and has been known to be used in behavioral studies, cognitive neuroscience and sleep monitoring. In this work a single channel wearable wireless EOG monitoring system is presented. The entire system is implemented on a double sided polymide flexible substrate. The recording silver electrodes are printed on the bottom side of the substrate whereas the EOG signal recording and transmission circuitries are implemented on the top side of the substrate with printed silver traces. The system is run by a rechargeable battery and uses a BLE 5.0 transceiver for wireless connectivity. Design considerations for the wearable EOG monitoring system are discussed in details. The system performance is validated by successfully monitoring different eye movements with it. Additionally, comparison between the EOG signals observed using the printed silver electrodes and commercial gold electrodes of same dimensions demonstrate that the printed electrodes provide similar EOG signal amplitude like the commercial gold electrodes. With a 5.2 gram mass and flexibility the system has potential for monitoring EOG signal without causing discomfort to the wearer.