Patent ID: 6347813
Filing Date: 2002-02-19
Classification: A63F

Abstract:
A multilayered set of sheets having concealed resonant devices comprising:a first sheet having a first and a second surface including graphics on said first surface; a pattern of conductive material adjacent to the second surface of said first sheet and having a predetermined resonant frequency; said pattern of conductive material surrounded by a second conductive pattern without a resonant frequency near said predetermined resonant frequency; a second printed sheet having a first and second surface including graphics on said first surface; a pattern of conductive material adjacent to the second surface of said second printed sheet and having a predetermined resonant frequency; said first and second sheets being positionable one over the other with the first surfaces of each visible to the user and the second surfaces thereof concealed from the user; said pattern of conductive material adjacent to the second surface of said second sheet being positioned at a different lateral location from said pattern of conductive material having a predetermined resonant frequency on said first sheet; whereby each of said patterns of conductive material having predetermined resonant frequency is individually detectable from the first surface of their respective sheet.