Tamper detection using bulk multiple scattering

Abstract

The multiple scattering of coherent radiation in an inhomogeneous medium is used to detect attempted intrusions into a protected area or into a tamper-proof package for such purposes as preventing the unauthorized detection and copying of electronic information used for authentication and coding in electronic commerce, communications, command, and control systems. A key advantage is that any intrusion into the sensed volume will produce a detected change in the measured intensity which will be equal to the full amplitude range if the intrusion is into a cylinder with radius comparable to the wavelength of the sensing radiation. The response of the medium can also be used to provide a unique identity key.