DYNAMIC MICRO-OPTIC SECURITY DEVICES, THEIR PRODUCTION AND USE

Disclosed are devices with dynamic optical properties suitable for use as security or authentication devices, for example for documents or items of importance or value, in order to help prevent counterfeit of the same. Such devices, at least in selected embodiments, enable observation of dynamic changes or moving entities within the device by collective imaging of the dynamic changes or moveable entities, the motion or position of which may otherwise be difficult to observe, or indiscernible to, the naked eye.