| abstract |
Systems and markers using magnetic or spin resonance phenomena for practical purposes are dislcosed. The use of magnetic resonance, spin resonance and spin-echo phenomena in systems for the surveillance, recognition, detection, sorting or monitoring of articles, stock or personnel are included. The applications of such systems include electronic article surveillance (theft prevention) and personnel verification. In one aspect, a detectable marker comprises a substrate which supports (internally or externally) a material which is capable of supporting a magnetic resonance. |