Shimizu has worked with the Nakagawa Laboratory on a system for museums that uses visible light to convey information about exhibits to PDAs held by visitors.

Viewers simply place their PDA in the path of the light coming from a nearby lamp in order to read and listen to information about the exhibit.

The lamp, which can be an LED light source or a fluorescent bulb, is programmed to blink in a way that transmits a stream of data bits to the PDA. The PDA reads this stream to identify the exhibit and then plays back prerecorded information. The lamp blinks so quickly that to viewers it seems like a steady light.

With visible light communications, the visitor knows exactly where to place the PDA in order to capture the signal. Some museums already have systems that use infrared light to trigger presentations in PDAs, but because IR light is invisible, these can be confusing to users.

Via Nikkei.

Related:

The Talking Lights communicate information that can be heard through an earpiece, seen on a handheld screen, or processed as data or control signals by a computer.

By a slight modification in the design of a fluorescent light ballast, the light can transmit data without visible flicker.

The system is being developed for use as an assistive technology for blind, deaf and hard of hearing users and for traumatic brain injury patients. It’s also being qualified to create other communication networks and enhance military systems (on the battlefield, for mine clearing, etc.)