Patent US 5,771,176

This invention in its preferred embodiment comprises an apparatus and process (including a computer program) for controlling unmarked lock-opening keys in a security systems, whereby the conventional metal keys used to unlock rooms or cars or other entities can be controlled even though unmarked. The technique of the invention effectuates such control through taking electronic photographs, creating a silhouette of the side of unmarked keys using their individual configurations on the edge, generating an individual and distinctive electronic signal, specific for each such key to generate a digital coordinate series of numbers for each key and inventorying each such identifying signal representing a key so that keys are recognized by these signals rather than numbers or codes marks on the key. Although marked keys can be utilized in such a system, it would be a waste of the identifying ability of the invention. Thus the greatest security benefits are obtained through the use of unmarked keys in the apparatus and process of the invention.