US Patent 7249854 Virtual digital shape projector

A projection system for projecting a shape onto a scene (e.g., the surface of an object, the body of a patient, or the like) so that the shape appears to be projected via a light beam emanating from a desired source location includes two or more projection assemblies for projecting planes of light which intersect the scene to form light stripes on the scene. The intersection of the light stripes defines a point of light projected onto the scene so that the point of light appears to emanate from the source location. The first and second projection assemblies rotate about first and second axes which extend through the source location for controlling the position of the point of light on the scene.