Off-screen touch interactive system with nearly-joint sensing projection point coordinate indication

The invention provides a touch device which is separated from a graphical interface display screen and provided with a man-machine interactive system with nearly-joint sensing projection point coordinate indication. The touch device can sense a coordinate of projection points when an object approaches a touch panel of the touch device, can also sense a coordinate of touch points when the object is contacted with the touch panel, and transmits two coordinate data to a graphical interface control module through a wired or wireless mode. The graphical interface control module is used for drawing a graphical interface and drawing indication points at corresponding positions on the graphical interface according to received coordinate data of the projection point, therefore positions of the projection points of the object close to the touch panel can be indicated and tracked continuously through a visual mode. When the object contacts with the touch panel, the graphical interface control module performs corresponding touch type graphical interface interactive operation according to the coordinate and movement of the touch points, and simultaneously indication points of the touch points can be drawn on the graphical interface.