OPTICAL MEMORY STORAGE AND RETRIEVAL SYSTEM

• US 3,765,749 A
• Filed: 05/23/1972
• Issued: 10/16/1973
• Est. Priority Date: 05/23/1972
• Status: Expired due to Term

• Current Assignee: John Thomas Lamacchia
• Original Assignee: John Thomas Lamacchia
• Inventors: LaMacchia, John Thomas
• Primary Examiner(s): Schonberg, David
• Assistant Examiner(s): McGraw, V. P.
• Application Number:
  US05/255,990
• Time in Patent Office: 511 Days
• Field of Search: 356/71 350/161,167 340/173LM,173TP
• US Class Current: 359/291
• CPC Class Codes: G11C 13/048 using other optical storage elements

Abstract

An optical memory element capable of recording many pages of information is provided by locating a thermoplastic (heatdeformable) resin memory sheet between a pair of fly'"'"''"'"'s eye lenses. One of these lenses serves the purpose of focusing readout optical radiation incident on a single desired page of the memory sheet, the readout optical radiation coming from one of a plurality of light sources, each of which correspond to a page of the memory sheet. The other fly'"'"''"'"'s eye lens focuses a page of write-in optical radiation onto the corresponding page of the memory element; and this second lens also serves the purpose of focusing the readout optical radiation after propagating through both the memory element and a Schlieren stop located between the memory sheet and this fly'"'"''"'"'s eye lens. An array of optical detectors, onto which the readout beam of optical radiation is focused, reads out a page of information at a time, corresponding to the particular one of the readout optical sources which is energized at that time.

Claims

1. An optical memory system which comprises:

a. a memory sheet of material whose optical transmission property at any selected page region can be locally modified by incident optical write-in radiation;

b. first and second lens matrices located on opposite sides of the sheet;

c. a first optical array of individual optical sources capable of producing a controllable pattern of optical write-in radiation incident upon the first lens matrix in a first direction and which is focused by each of the lenslets in the first lens matrix on a different page portion of the sheet, whereby the optical transmission property of the sheet can be modified in accordance with the pattern at one or more of said page portions; and

d. a second optical array of individually controllable sources of optical readout radiation, each of which is arranged to furnish readout optical radiation incident in the opposite direction from the first direction upon at least one diffeRent lenslet in the second lens matrix, thence past an optical stop means in an array of such optical stop means and through a lenslet of the first lens matrix for focusing on an array of photodetectors, each of such lenslets arranged to transmit said readout optical radiation to a different page portion of the sheet.

2. The system recited in claim 1 which further includes an array of photodetectors upon which optical radiation from the second optical array is incident after transmission respectively through the second lens, the sheet, and the first lens;

and each photodetector being in optical registry with a different one of the optical sources of the first optical array.

3. The system recited in claim 1 in which the memory sheet comprises a thermoplastic material.

4. The system recited in claim 3 in which the memory sheet comprises a thermoplastic resin.

5. The system recited in claim 3 in which there is further provided the array of optical stop means, said stop means located between the memory sheet and the first lens such that each of said stop means absorbs optical radiation from a corresponding different one of the page portions in the memory sheet in the absence of any previous write-in radiation from the first optical array incident upon said page portion when said page portion was simultaneously sensitized to the write-in radiation incident upon said page portion.

6. The system recited in claim 3 which further includes means for locally developing at least a page portion of the thermoplastic material.

7. The system recited in claim 6 in which the means for sensitizing the material includes means for controllably heating the material at selected page portions.

8. The system recited in claim 6 in which the means for locally developing the material includes means for applying a heat pulse locally to said material.