An automotive safety feature that alerts drivers when a vehicle is coming up from behind at a fast clip but has not yet reached their side view mirrors. A blind spot alert is also sounded when the turn signal indicator is employed and a car is in the blind spot. As of 2020, cars employ radar, but LIDAR may be used in the future. See automotive safety systems
Blind Spot Information (BSI) System
In this 2017 Honda CR-V example, icons on both side mirrors flash whenever radar underneath the rear bumpers detect a vehicle entering the blind spot. If the turn signal is on, an audible alert is also provided.