Thin vacuum panel display device

• US 4,280,125 A
• Filed: 07/27/1979
• Issued: 07/21/1981
• Est. Priority Date: 07/27/1979
• Status: Expired due to Term

• Current Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Original Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Inventors: Kazan, Benjamin
• Primary Examiner(s): Curtis, Marshall M.
• Application Number:
  US06/061,349
• Time in Patent Office: 725 Days
• Field of Search: 340/713, 340/714, 340/720, 340/770, 340/772, 340/781, 340/795, 340/166 EL, 340/380, 340/703, 340/704, 250/213 A, 250/213 VT, 250/227, 250/578, 250/368, 358/241, 358/230
• US Class Current: 340/815.66
• CPC Class Codes: G09G 1/20 using multi-beam tubes G09G1/26, G09G1/28 take precedence
• CPC Class Codes: H01J 31/126 using line sources
• CPC Class Codes: H01J 31/505 flat tubes, e.g. proximity focusing tubes

Abstract

A thin vacuum panel cathode ray display device for providing visible information upon a phosphor layer, on a viewing wall, in response to electron beam excitation. Electron beams are generated by cathodes on an electron source wall spaced from the viewing wall. The cathodes comprise an array optical waveguides each coated with a photoemissive material. Between the cathode array and the phosphor layer, and adjacent to the cathodes, is an array of grid members for selectively controlling the flow of electrons to the phosphor layer in response to low voltage signals applied to the grid members. Light energy is sequentially introduced into each of the waveguides while simultaneous control signals are applied to all of the grid members to provide line-at-at-time information display upon the phosphor layer.

Claims

1. A vacuum panel display device including a viewing wall having thereon a phosphor layer on which information is displayed in response to electron beam excitation, the improvement comprising:

an electron source wall spaced from and parallel to said viewing wall,

a generally planar array of parallel, elongate optical waveguide elements supported upon said electron source wall, a portion of each waveguide element bearing a coating of photoemissive material along its length

a light energy source coupled to each of said waveguide elements for selectively introducing light into and along the length of each of said selected waveguide elements to cause photoemission of electrons from said coating along the length of said selectively illuminated waveguide elements,

means for controlling the flow of electrons to said phosphor layer from preselected areas of said coating along the length of each selectively illuminated waveguide element and

timng means associated with said light energy source for sequentially illuminating each of said optical waveguide elements in said array.

2. The vacuum panel display device defined in claim 1 wherein said optical waveguide elements comprise optical fibers.

3. The vacuum display device defined in claim 1 wherein said means for controlling the flow of electrons from preselected areas along said selectively illuminated waveguide element to said phosphor layer comprises an array of control wires lying generally in a plane parallel to and spaced from said array of waveguide elements such that said control wires are disposed at an angle relative to said waveguide elements and

a parallel video signal source connected to said array of control wires to simultaneously act upon each of said control wires for selectively switching given wires, to allow electrons to pass from said preselected areas of said coating on a single waveguide element to said phosphor layer.

4. The vacuum panel display device defined in claim 3 wherein each of said control wires is connected to

a bias potential source of sufficient magnitude to normally block passage of electrons from a portion of said photoemissive material on said waveguide element to said phosphor layer.

5. The vacuum panel display device defined in claim 4 including:

first timing means connected to said light energy source for sequentially illuminating each of said optical waveguide elements in a timed manner,

second timing means connected to said parallel video signal source for stepping subsequent scan lines of signals from a supply to said parallel video signal source, and

third timing means connected to said first and second timing means for stepping subsequent scan lines of signals to said control wires as each subsequent optical waveguide element is illuminated.

6. The vacuum panel display device defined in claim 1 wherein said electron source wall carries an array of elongated opaque spacers for optically separating said waveguide elements from one another.

7. The vacuum panel display device defined in claim 6 wherein said means for controlling the flow of electrons comprises an array of control wires lying in a plane generally parallel to and spaced from said array of waveguide elements and disposed substantially perpendicularly to said elements, and said control wires are supported upon said opaque spacers.

8. The vacuum panel display device defined in claim 1 wherein said viewing wall includes a conductive layer which is maintained at a positive electrical potential for accelerating electrons which are allowed to pass said controlling means.

9. The vacuum panel display device defined in claim 1 wherein said light energy source comprises a laser device and a scanning device for optically coupling the laser beam with each of said optical waveguide elements.

10. The vacuum panel display device defined in claim 1 wherein said phosphor layer comprises plural phosphors capable of emitting different colors.