OPTICAL MEMORY DEVICE FOR WRITING IN AND READING FOR INFORMATION

• US 3,860,917 A
• Filed: 05/09/1973
• Issued: 01/14/1975
• Est. Priority Date: 05/12/1972
• Status: Expired due to Term

• Current Assignee: Jean-Pierre Huignard, Luigi D. Auria
• Original Assignee: Jean-Pierre Huignard, Luigi D. Auria
• Inventors: Huignard, Jean-Pierre, Auria, Luigi D.
• Primary Examiner(s): Fears, Terrell W.
• Application Number:
  US05/358,545
• Time in Patent Office: 615 Days
• Field of Search: 340/173LM 346/74
• US Class Current: 365/127
• CPC Class Codes: G11C 13/04 using optical elements ; using other beam accessed elements, e.g. electron or ion beam

Abstract

The present invention relates to the optical storage of information items upon a photosensitive support. The writing in of any group of N information items is performed by displaying these items with an array of N sources and by projecting images of said array onto M adjacent areas of the support. Shutter means are provided for selectively limiting the writing in to anyone of said areas. Read out is performed by selectively illuminating anyone of said areas and by projecting back an image thereof which is sensed by an array of N photoelectric elements. The shutter means remain fully open during read out.

Claims

1. Optical memory device for writing in and reading-out information items consisting of M groups of N binary digits stored in a photosensitive support building up the data plane of said optical memory device, said device comprising:

optical display means controlled by the information items pertaining to anyone of said groups for supplying a first pattern of optical data, multiple imaging means projecting onto said data plane M adjacent images of said first pattern arranged for forming a further pattern of M adjacent storage areas, shutter means for selectively limiting to anyone of said storage areas, the writing in of said informating items, photoelectric read-out means arranged in accordance with said first pattern, illuminating means arranged in accordance with said further pattern for selectively illuminating anyone of said storage areas, and optical reflecting means optically conjugating the sensitive face of said photoelectric read-out means with the emissive face of said optical display means.

2. Optical memory device as claimed in claim 1, wherein said shutter means comprise masking means building up an exposure window and translation means for displacing said exposure window along twO distinct directions substantially parallel to said data plane.

3. Optical memory device as claimed in claim 2, wherein said masking means build up during the writing in phase an exposure window surrounding anyone of said storage areas;

said masking means further building up during the reading-out phase a window having an aperture at least equal to the portion of said data plane covered by all said storage areas.

4. Optical memory device for writing in and reading-out information items consisting of M groups of N binary digits stored in a photosensitive support building up the data plane of said optical memory device, said device comprising:

optical display means controlled by the information items pertaining to anyone of said groups for supplying a first pattern of optical data, multiple imaging means projecting onto said data plane M adjacent images of said first pattern arranged for forming a further pattern of M adjacent storage areas, shutter means for selectively limiting to anyone of said storage areas, the writing in of said informating items, photoelectric read-out means arranged in accordance with said first pattern, illuminating means arranged in accordance with said further pattern for selectively illuminating anyone of said storage areas, and optical reflecting means optically conjugating the sensitive face of said photoelectric read-out means with the emissive face of said optical display means;

said optical reflecting means comprising a retractable mirror;

said mirror being retracted during one of the writing-in and reading-out phases.

5. Optical memory device for writing in and reading-out information items consisting of M groups of N binary digits stored in a photosensitive support building up the data plane of said optical memory device, said device comprising:

optical display means controlled by the information items pertaining to anyone of said groups for supplying a first pattern of optical data, multiple imaging means projecting onto said data plane M adjacent images of said first pattern arranged for forming a further pattern of M adjacent storage areas, shutter means for selectively limiting to anyone of said storage areas, the writing in of said informating items, photoelectric read-out means arranged in accordance with said first pattern, illuminating means arranged in accordance with said further pattern for selectively illuminating anyone of said storage areas, and optical reflecting means optically conjugating the sensitive face of said photoelectric read-out means with the emissive face of said optical display means;

said optical reflecting means comprising a fixed transparent plate carrying a selective optical filtering layer;

said layer allowing the reflection of the radiation emerging from one of said optical display and illuminating means, and said layer simultaneously allowing the transmission of the radiation of distinct wavelength emerging from the other of said last mentioned means.

6. Optical memory device for writing in and reading-out information items consisting of M groups of N binary digits stored in a photosensitive support building up the data plane of said optical memory device, said device comprising:

optical display means controlled by the information items pertaining to anyone of said groups for supplying a first pattern of optical data, multiple imaging means projecting onto said data plane M adjacent images of said first pattern arranged for forming a further pattern of M adjacent storage areas, shutter means for selectively limiting to anyone of said storage areas, the writing in of said informating items, photoelectric read-out means arranged in accordance with said first pattern, illuminating means arranged in accordance with said further pattern for selectively illuminating anyone of said storage areas, and optical reflecting means optically conjugating the sensitive face of said photoelectric read-out means with the emissive face of said optical display means;

said optical display and illuminating means comprising electro-luminescent diodes respectively arranged along said first and further patterns.

7. Optical memory device as claimed in claim 2, wherein said masking means comprise two opaque films;

each of said film including a transparent slot;

said films being slidably mounted for respectively displacing along said distinct directions;

each slot being elongated and oriented in relation to the other slot for building up said exposure window.

8. Optical memory device as claimed in claim 7, wherein said slots are rectangular;

the width of said slots being slightly larger than that of anyone of said storage areas;

the length of said slots being slightly larger than the dimensions of the portions of said data plane carrying all said storage areas.

9. Optical memory device as claimed in claim 7, wherein each of said films further comprise a transparent zone extending along the whole dimensions of the portion of said data plane carrying all said storage areas;

the transparent zone of one of said films being brought into coincidence with the transparent zone of the other of said films during the reading-out phase for completely withdrawing said exposure window.

10. Optical memory device as claimed in claim 1, wherein said multiple imaging means comprise an objective lens cooperating with a plurality of coplanar lenses distributed in accordance with said further pattern;

said illuminating means comprising an array of coplanar lenses distributed in accordance with said further pattern.