Remote infrared audible signage

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Remote infrared audible signage (RIAS) helps print-disabled people access information from signs in buildings. It was developed by the Smith-Kettlewell Eye Research Institute (originally Talking Signs). Infrared transmitters repeatedly broadcast spoken content of a sign through wireless signals. The 1979 early version, Talking Lights, evolved into Talking Signs and is now installed worldwide. A user uses a handheld or glasses-mounted infrared receiver that is sensitive to a direct line-of-sight IR beam and provides feedback when aimed at the sign and close. The system works indoors and outdoors, with invisible, silent beams that don’t disturb the surroundings. The idea traces back to Bell’s photophone and has been used in military and consumer tech. RIAS is noted in US building code 703.7 and in a U.S. Access Board report.