Photographic flash light equipment

摘要

The flash unit has a colour filter made of plastic material or glass and other colours instead of red can be filtered out. The flash is activated by a sensor that can be a photocell, light sensitive diode or a transistor and this sensor is triggered by operation of any picture-taking mechanism or camera, e.g. by road traffic authorities. When its colour filter has the same colour range as the equipment itself, it will make any photograph unrecognisable.