Patent ID: 8115699

Claim:
A position detecting system comprising: a positional information transmission device for transmitting positional information; a mobile terminal for receiving the positional information; and a control device capable of communicating with the mobile terminal, the positional information transmission device including: a plurality of positional information transmitters arranged in an array on a ceiling for transmitting the positional information to a plurality of unit spaces which are each uniquely assigned to the plurality of positional information transmitters, wherein each of the positional information transmitters include a plurality of infrared emitters which emit the positional information through a modulated infrared signal, the mobile terminal carried by a user and including: first display unit for displaying a first image; first receiving programmed logic circuitry for receiving the positional information transmitted from the positional information transmitters; first image processing programmed logic circuitry for changing the first image in accordance with the positional information received by the first receiving programmed logic circuitry; operation elements for accepting an instruction inputted by a user; and transmission programmed logic circuitry for transmitting, to the control device, current positional information corresponding to the positional information received by the receiving programmed logic circuitry, said current positional information generated by current positional information generating programmed logic circuitry, and operation information indicating the instruction inputted by the user through the operation elements, the control device arranged separately from the mobile terminal and the positional information transmission device and including: second display unit arranged on a floor for displaying a second image; second receiving programmed logic circuitry for receiving the current positional information and the operation information transmitted from the mobile terminal; and second image processing programmed logic circuitry for changing the second image in accordance with the current positional information and the operation information received by the second receiving programmed logic circuitry, wherein each of the positional information transmitters transmits the positional information for a predetermined number of times at an interval of a predetermined period of time, and the current positional information generating programmed logic circuitry of the mobile terminal measures, for the predetermined period of time, the number of times each piece of the positional information was received by the first receiving programmed logic circuitry, and generates the current positional information based on said measured number of times each piece of the positional information was received and the predetermined number of times each of the positional information transmitters transmitted the positional information.