Handy information display system

Abstract

A handy information display system is disclosed. The system has three main components: a light emitting diodes (LED) array display board (20), an information server (10) and a portable unit (30). The LED array display board (20) includes a plurality of light emitting diodes and photodetectors. It is used to display alphabets, numbers and simple graphics. While it visually gives an effectively stationary message display, the LEDs can also be modulated to transmit high frequency signals. The modulating frequency should be high enough to be imperceptible by humans. An information server (10) controls both message display and signal transmission. The portable unit (30) is equipped with an optical transceiver (31) and a visual display unit. The optical transceiver can detect the signals transmitted from the LED array display board (20). The visual display unit then shows the information corresponding to the received signals.