Method and device for inputting coordinate-position and a display board system

摘要

The coordinate-position input device has a frame with a reflecting member for recursively reflecting light provided in an inner side from four edges of the frame forming a rectangular form. Two optical units irradiate light to the reflecting members and receive the reflected light. With the mounting member(s) the frame can be detachably attached to a white board. The two optical units are located at both ends of any one of frame edges forming the frame, and at the same time the two optical units and the frame body are integrated to each other.