MULTIMODE APPARATUS AND METHOD FOR MAKING SAME

摘要

An apparatus operable in touch-input mode and scanning mode uses a light guide and a camera to look through a slanted facet at one corner of the light guide. The light guide has an upper surface for placing a touch object or an item for scanning. An angular sensitive grating is located on lower surface having fringes such that when a light beam directed from a location P on upper surface toward lower surface at a predefined direction, it is diffracted by the grating and guided toward the slanted facet. The diffracted beam exits the slanted facet at an exiting angle indicative of the location P. When an object or item is placed on upper surface, it causes changes in exit beam intensity. From exiting angles and intensity changes, a camera is able to locate touch objects or to acquire an image of the scanned item.