A plasma display panel equipped with a front substrate and a back substrate facing each other to form a discharge space. A first card is employed for accessing account data of a corresponding account. The position of the positions defined by the matching partial areas, which according to the matching step is the most probable position in the position-coding pattern for the imaged partial area is accepted as the decoded position. The message creator 1 transmits the program tag capture request to the program display controller 2 and then, when the program tag is returned, inserts it into the message 5.