A communication system for a marketing area locates a light signal generating system and a master computer at a control center and delivers message bearing light signals over optical channels to predetermined subdivisions of the marketing area. Message relay units are provided on the shopping carts in the marketing area for transmitting audio and/or visual messages to the shopper. Among the visual messages transmitted are those which visually display a list of items available for purchase and on display in the marketing area, a graphics display of the marketing area and the merchandise display facilities therein, a video picture which is often of a product or item available for purchase in the marketing area and a traveling word message.
The relay units disclosed have a computer which operates under the control of the master computer, a signal recieving system and various message signal storage facilities as well as a message transmission system that includes a visual display device and an audio transmission device. Various computer controls are provided for shopper use, including controls that facilitate the recording of items destined for purchase by the shopper and which facilitate the generation of indicia on the graphics display indicative of the item locations in the marketing area and a control that changes the size and viewing mode of the graphics display of the marketing area.
Procedures for guiding the shoppers about the marketing area and for delivering the messages to the shoppers in the marketing area are also considered.