Keyless holographic lock

A keyless angular-invariant holographic lock capable of producing a command signal when a user presents an identification to the lock, wherein for angular invariancy the lock comprises:

• an input element, including a transparent window against which the user presents the identification and rotates if for angular alignment with a prestored identification previously stored in form of a Fourier-hologram;
• a matched optical filter upon which the prestored unique identification is stored in the form of said Fourier-hologram;
• a coherent light-source for illuminating said identification with a beam at said transparent window;
• means for projecting upon said optical matched filter a reflected coherent beam from the window, said reflected coherent beam having been encoded by said identification at the window;
• and
• optical means for registering a correlation signal, wherein the correlation signal is formed during optical comparison of the pre-stored identification with the presented identification during rotation of the presented identification, and for generating the command signal only when the correlation signal is unambiguously present, wherein the correlation signal is a first-stage correlation signal, and wherein the matched optical filter is produced in the form of a generalized hologram in which a second unique identification is pre-stored, and further comprising:
• a second transparent window upon which the user presents a second identification;
• a lid, rotatably attached to the second window and possessing a mirrored layer;
• and
• means for registering a second-stage correlation optical signal formed in the process of comparing the first-stage correlation signal from the matched optical filter with the presented second identification, and for forming the command signal only when the second-stage correlation optical signal is unambiguously present.

A method of activating a locking device, comprising the steps of:

• storing a unique identification in the form of a Fourier hologram indicative of a person authorized to activate said device,
• presenting an identification to a transparent window and varying the angular orientation of the identification as it is presented,
• reflecting a beam from the window during variation of the identification's angular orientation, so that the reflected beam is encoded by said presented identification and the reflected beam is projected onto the Fourier hologram,
• continuously in time comparing said reflected beam optically with said hologram, and generating a command signal when an optical correlation signal is present between the presented identification and said Fourier hologram, further comprising the steps of:
• encoding a reference beam with the unique identification and with a second identification, and directing said encoded reference beam to a self-developing medium, thus forming a generalized matched optical filter in which the unique identification and the second identification are holographically stored;
• and
• illuminating a second transparent window with the optical correlation signal, but only in the case that the optical correlation signal is present, wherein the optical correlation signal is an optical signal which reconstructs the stored second identification.