A system, which allows computer input without keyboard, is proposed. The system utilizes display-mounted Web camera for acquisition of users face and also display-mounted lamp for illumination to users. It is found that the proposed system allows computer input almost perfectly (90%) if the distance between user and display is within 30cm and if keyboard image is displayed onto a 19 inch of computer display (5cm of key distance) with 40W of fluorescent light utilized normal illumination from both side of the display. It is also found that the proposed system allows user movement because moving picture of the user face acquires in a real time basis. The relation between allowable movement of the users' motion and success rate and the relation between signal to noise ratio as well as contrast of the acquired users' image and success rate are clarified.