Optical Device Indicating a Safe Free Path to Blind People

An active optical pathfinder using a LED and a photodiode is implemented as an electronic travel aid to improve the mobility of persons who are blind. The protected path is optimized by using radiometric calculations. Protection zones for typical configurations of obstacles are studied: an opening, a side panel, a front panel, and a post. The results in real configurations such as parked cars, trees, and dustbins are presented too. Finally, we explain how the device can be used in real life by visually impaired people, in conjunction with the typical white stick.