Optically encoded physical keys

Abstract

Lock based security has been used since the early days of human history. Whenever people have wanted to keep their possessions safe, they have used locks to hinder those who would want to access their belongings against their will. As such, an arms race has ensued, consisting of ever more complex locks, and lock-defeating methods. This thesis is not the first time that optics have been used in locking mechanisms, but it puts forth a robust, versatile, and economical security system employing optics based on the spirit of physical keys. The proposed system uses a physical key with embedded optical fibers routed between optical ports on its surface. The corresponding reader scans the key by sequentially illuminating each port, and observing where the light exits the key. The reader then builds a matrix representing the internal connections of the key, and compares it to each key's unique identifying matrix to determine whether to grant or deny access to the current user.