| 摘要 |
PURPOSE:To know that a person carrying a portable transmitter corresponding to a second telephone set is near a first telephone set by displaying the telephone number of the first telephone set on the second telephone set. CONSTITUTION:For example, when the possessor of a telephone set T3 moves from the set place of the telephone set T3 to the set place of a telephone set Tn, the telephone set Tn detects oscillating frequencies f3 inherent in the possessor of the telephone set T3, the telephone number corresponding to the f3 stored into a storage part 8 beforehand is fetched, and it is sent through a private branch exchange to the telephone set T3. Further, the telephone set T3 displays the telephone number on a display part 19. Thus, that the possessor of the telephone set T3 has moved near the telephone set Tn is known. |
