Keying ki - distinction manner and its keying ki - distinction device null of ki - bo -

摘要

PURPOSE:To convert the depression of a key into an electric signal and to discriminate the depressed key without using a mechanical connection point. CONSTITUTION:An optical bead 14 from a laser diode 12 is refracted by the prism 16 (16-3) of the depressed key 18 and the light receiving surface 34a of an image sensor 34 is irradiated with the optical beam. The electric signal corresponding to the irradiation position of the optical beam 14 is outputted from the image sensor 34 and the depressed key is discriminated by an output signal from the image sensor.