PURPOSE: To obtain an input terminal device without giving much fatigue to operators, by detecting the displacement of each bead of an entry means consisting of five beads freely inserted.

CONSTITUTION: Five beads 1 are freely inserted to a cylindrical shaft 2, a light emitting element 3 is provided at the outside of the shaft 2, the shaft 2 is hollow as an optical signal transmitter 4 to transmit optical signals from the element 3. The shaft 2 is provided with seven openings 5 as a light emitting output terminal branched from the device 4 and photodetectors 6 and electric signal terminals 7 are provided at the outside. The openings 5 correspond to the beads 1 and openings 6 correspond one to one to the elements 6. In inputting a figure, e.g., 1, the bead as the figure 1 is moved upward by a distance to shield an optical signal transmitting the openings 5. In this case, the optical signal from the element 3 passes through the device 4 and reaches the element 6 from the openings 5 and the terminals 7 to input the bead 1 as a figure 1. This is almost the same for other figures above 2. Thus, the input device offers less fatigue to the operator, because of no keyboard device.