Electric field-driven particle manipulation for optical sensor cleaning

Contaminants on the lens surface of optical sensors block and scatter incident light, deteriorating the performance of optical sensors. The cleaning method of solid particles using non-mechanical means is desirable in many industries which utilize real-time imaging cameras or LiDAR sensors. Recent studies of particle manipulation using an electric field have mainly focused on application to photovoltaic panels for power generation. This study presents the use of an electric field to remove contaminants such as sand, dust, pollen, and other solid particles from the surface of a cover glass of optical sensors. Firstly, we investigated the electrodynamic characteristics of solid particles with different material properties and physical sizes in time-varying electric fields. Secondly, an electrodynamic actuator consisting of multi-channel electrode patterns and electrical insulating layers on a transparent substrate was designed with consideration for optical transmittance and electrical power. Thirdly, cleaning performance was quantified by measuring the covered area with contaminants. Through comparison of the cleaning performance, we optimized the actuator design and driving signals. These experimental results provide a new practical approach to the industrial application of an electrodynamic particle manipulator.