The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 04, 1977
Filed:
Sep. 23, 1975
Horst Kiemle, Neuried, DT;
Siemens Aktiengesellschaft, Berlin & Munich, DT;
Abstract
A holographic storage device which is capable of enabling both recording of information to be stored and retrieving information characterized by a portion of a beam of coherent light being directed onto a sub-hologram of an illumination hologram to create an illuminating beam which is projected on a modulator matrix which creates an object wave that is projected onto the storage medium during a recording operation. The device further includes a detector matrix utilized during the retrieval operation and both the detector matrix and the modulator matrix are separated from the storage medium by transparent bodies having an index of refraction greater than 1. In one embodiment, at least two of the transparent bodies include light splitting or distribution surfaces which split off a portion of the beam passing therethrough, the illumination hologram is preferably a surface relief reflection hologram and a retrodirective mirror is utilized to direct the beam passing through the first beam splitter to a second beam splitter to be projected onto the storage medium. In a second embodiment, the coherent beam of light is projected through a transparent body, the storage medium and received by a retrodirective mirror which directs it on the illumination hologram. In this embodiment, the illumination hologram can be in the same plane as the storage medium and the modulator matrix is a reflective matrix to reflect the modulated object beam back onto the storage medium. In a similar arrangement of the embodiment, the modulator matrix is a transparent matrix and an additional transparent body is arranged on the opposite side thereof with the illumination hologram disposed on opposite surfaces.