Abstract: A security tag or device for use with a product package. The security tag has an optical sensor that detects ambient radiation (or light, if any) within the package interior (e.g., from a source outside the package). The optical sensor is temporarily limited from detecting the ambient radiation within the package by a lock section. A device may be provided to activate the lock section so that the optical sensor can detect light in the package. The optical sensor can be aligned with an opening in the package after the lock section is activated. After calibration, the optical sensor is used to determine changes in detected ambient radiation within the package. The security tag has an alarm adapted to provide an alert when a change (e.g., above a threshold) in intensity of ambient radiation within a package is detected by the optical sensor.

Abstract: A security tag or device for use with a product package. The security tag has an optical sensor that detects ambient radiation (or light, if any) within the package interior (e.g., from a source outside the package). The optical sensor is temporarily limited from detecting the ambient radiation within the package by a lock section. A device may be provided to activate the lock section so that the optical sensor can detect light in the package. The optical sensor can be aligned with an opening in the package after the lock section is activated. After calibration, the optical sensor is used to determine changes in detected ambient radiation within the package. The security tag has an alarm adapted to provide an alert when a change (e.g., above a threshold) in intensity of ambient radiation within a package is detected by the optical sensor.