Abstract: Virtual key pads assigned to correspond to function commands conventionally executed in response to operating real key pads, are scanned by an optical scanning apparatus for recognizing if they have been touched by user or which among them have/has been touched, and for executing the function commands corresponded by that/those which was/were touched, whereby the virtual key pads act as real key pads, thereby real key pads are no longer necessary. Also a cover-mat with virtual key pads and more than one window thereon is suggested to conveniently adapt a scanning apparatus to various applications.