Acoustic traffic crossing aid for blind persons - has traffic light condition signalled by buzzer generating two separate sounds

摘要

An aid for blind persons at traffic crossings utilises acoustic signal generators to distinguish between red and green conditions. The traffic light system (A) has an associated selector with a raised symbol indicating the direction of passage required. The safe crossing condition is signalled by a continuous note emitted by a buzzer, whereas the stop condition causes an intermittent signal to be generated. Each traffic light located on a corner has two such selectors; one for each direction.