Optical information storage system

• US 3,982,151 A
• Filed: 11/19/1973
• Issued: 09/21/1976
• Est. Priority Date: 10/23/1967
• Status: Expired due to Term

• Current Assignee: Corning Glass Works Inc. (Corning Incorporated)
• Original Assignee: Corning Glass Works (Corning Incorporated)
• Inventors: Megla, Gerhard K., Ludovici, Bruno F.
• Primary Examiner(s): Segal, Robert
• Application Number:
  US05/416,976
• Time in Patent Office: 1,037 Days
• Field of Search: 313/91, 313/92 LF, 313/465
• US Class Current: 313/465
• CPC Class Codes: G11C 13/041 using photochromic storage elements G11C13/042 takes precedence
• CPC Class Codes: H01J 29/14 acting by discoloration, e.g. halide screen
• CPC Class Codes: H01J 29/892 using fibre optics
• CPC Class Codes: Y10S 348/902 Photochromic

Abstract

An optical information storage system is disclosed which comprises a cathode ray tube having a photochromic fiber optic face plate on which data can be written by appropriate modulation and deflection of the electron beam. The readout function is accomplished by scanning appropriate portions of the phosphor by an electron beam of reduced intensity. Light which passes through the face plate is detected by a photocell.

Claims

1. An optical information storage system comprising

a cathode ray tube having a face plate consisting of a plurality of light-conducting optical fibers, each fiber having a core of photochromic glass of selected refractive index and a cladding on said core of light transmitting material of relatively lower refractive index, said fibers being arranged in side-by-side parallel contacting relation to each other in a hermetically sealed bundle,

a layer of phosphor adjacent said face plate within said cathode ray tube,

means for directing an electron beam on said layer of phosphor,

means for changing the energy level of said electron beam,

output means disposed on that side of said face plate opposite said phosphor layer in light receiving relationship with respect to said face plate for generating an electrical signal that is related to the intensity of the light emerging from the fibers of said plate, and

means for applying a digital input signal to said means for changing the energy level of said electron beam.

2. An optical information storage system in accordance with claim 1 which further comprises means for applying to said means for changing the energy level of said electron beam a readout bias voltage of lower intensity than that of said digital input signal.

3. An optical information storage system in accordance with claim 2 wherein said output means comprises a photo cell.

4. An optical information storage system in accordance with claim 3 which further comprises means disposed on that side of said face plate opposite said phosphor layer for directing onto said face plate light, the wavelength of which is such that it erases information stored in said face plate.