of functions in the brain is well known as brodmann brain mapping consequently a brain function to be used for controlling of equipment can be selected by selecting a position in the head to be illuminated by the laser light in this embodiment the light projecting tip of the optical fiber 1 7 is fixed at a position of the motor area brodmann 39 s area 4 in the brain handling movement of a hand for the purpose of using brain function signals intended for movement of a hand a light having a wavelength of 800 nm from the semiconductor laser element 90 and modulated with a frequency of 1 khz is projected from the tip of the optical fiber 1 7 onto the head and a portion of the projected light passes through the area of the cerebrum handling movement of a hand and enters an end of the light detecting optical fiber 1 8 and is converted into electrical signals by the photodetector 92 the lock in amplifier 93 selectively extracts signal components having a modulating frequency of 1 khz from the electrical signals this selection eliminates influences not originating from the semiconductor laser element 90 that is the influences caused by external lights the output from the lock in amplifier is converted into digital signals by the a d converter and is then supplied to the control device 95 the control device 95 displays the signal intensity based upon the signals supplied judges if the change of the signal intensity matches a predetermined pattern and sends an equipment control signal generating command to a control signal generating device based upon the judgment this procedure will be described later in this embodiment brain function signals handling movement of a.