PROBLEM TO BE SOLVED: To detect a weak biological signal and operate an external apparatus.SOLUTION: An interface device 10 includes a biological signal detection sensor 20, a differential amplifier 30, an amplification and filter circuit 40, an AD converter 50, a control unit 60, a transmission circuit 70, and a monitor 80. The control unit 60 comprises a micro computer for executing a control program, and converts respective biological signals amplified by the amplification and filter circuit 40 into temporal axis data so as to generate a control signal to be output to an external apparatus 110. Also, the control unit 60 includes a temporal axis data conversion means 62 for converting the biological signals acquired by the biological signal detection sensor 20 as the temporal axis data, and a control signal conversion means 64 for generating a control signal corresponding to the external apparatus based on the temporal axis data.
