RiPAL a small device when attached to a light source, such as a vehicles reversing light, will sound an audible alarm.

摘要

RiPAL Abstract A device to protect people from injury from reversing vehicles, and to warn the driver to check behind the vehicle, by converting the light from the reversing light into a loud warning similar to the warnings given by trucks reversing. 30 Lx 25 H x 15 D mm Alarm Aperture under to sense light change )