Electro-optical transducer and storage tube

Claim 2

An electro-optical transducer responsive to a projected energy beam comprising a bistable switch having in layered sequence a semiconductor layer, a dielectric barrier layer, and a tunnelling layer; elemental contacts on said bistable switch attached on said tunnelling layer on the side opposite said dielectric barrier layer, said elemental contacts defining areas of said bistable switch for preferential switching; an electrode layer in contact with one side of said bistable switch; means for providing a visual display in response to an electric field of predetermined magnitude applied thereacross formed as a layer on the other side of said bistable switch; an optically transparent conductive coating in contact with said means for providing a visual display; and a transparent face plate adjacent said transparent conductive coating for supporting said means for providing a visual display; so that when an electrical voltage sufficient in magnitude to provide said predetermined electric field magnitude is applied across said electrode and said optically transparent conductive coating and the projected energy beam has sufficient energy and is directed to impinge upon said electrode, said bistable switch is triggered into a high conductance state and the voltage maintains the high conductance state, thereby causing said means for providing a visual display to luminesce and provide an image which corresponds to the points of impingement of the energy beam which has fine definition for sufficiently high density arrays of said elemental contacts, and which is maintained indefinitely until the voltage is removed.

Claim 3

An electro-optical transducer as in claim 1 together with an opaque insulating layer between said bistable switch and said means for providing a visual display to minimize feedback of light from the means providing a visual display to the bistable switch.

Claim 4

An electro-optical transducer as in claim 1 wherein said bistable switch is oriented so that said semiconductor layer is disposed toward said means for providing a visual display.

Claim 5

An electro-optical transducer as in claim 1 wherein said electrode layer is disposed adjacent said semiconductor layer, and wherein said elemental contacts are disposed toward said means for providing a visual display.

Claim 6

An electro-optical transducer as in claim 4 for use in an evacuated environment, wherein said means for providing a visual display is an electrochromic layer, and said electrode layer is transparent, together with a fiber optics face plate adjacent to said electrode layer, and a phosphor coating on the side of said fiber optics face plate opposite said electrode layer, whereby when said phosphor coating is struck by the projected energy beam, light is emitted thereby, which is transmitted by said fiber optics face plate to said electrode, and said voltage must be reversed after removal to erase said image.

Claim 7

An electro-optical transducer as in claim 1 wherein said semiconductor layer is N type silicon having a thickness such that the depletion layer does not penetrate therethrough, and wherein said bistable switch layers are disposed so that said semiconductor layer is adjacent to said means for providing a visual display, whereby effects from feedback of light from said means for providing a visual display to said semiconductor layer are overcome.

Claim 8

An electro-optical transducer as in claim 1 wherein said means for providing a visual display is an electrochromic layer, said electrode layer is transparent, and the projected energy beam is a light beam, whereby a reverse voltage must be applied between said electrode and said optically transparent conductive coating after said voltage is removed to erase said image.

Claim 9

A storage tube of the type including an evacuated envelope, an electron gun disposed at one end of said envelope for projecting an electrOn beam carrying signal, an electro-optical transducer disposed at the other end of said envelope for receiving said beam and being responsive thereto to provide and form a display on a face of said envelope adjacent thereto, said electro-optical transducer comprising, a bistable switch for switching an electrical signal applied on the electron gun side of said electro-optical transducer, a plurality of electrically conductive areas on said bistable switch for application of an electrical potential for causing said bistable switch within the adjacent bistable switch body to transition from a low conductivity to a high conductivity state responsive to signals of predetermined magnitude carried by said electron beam and so that said bistable switch is maintained in said high conductivity state by an electric field of predetermined magnitude resulting from said electrical potential applied thereacross, means for providing a visual display of the type which emits light responsive to an electric field of predetermined magnitude applied thereacross formed as a layer having one face electrically connected with one face of said bistable switch and the other face disposed to emit light at the face of said envelope, contact means applied to the other face of said bistable switch forming an ohmic connection to said other face, and optically transparent contact means applied to the other face of said means for providing a visual display to form ohmic connection thereto, whereby a voltage up to 200 volts can be applied across said bistable switch and said visual display layer, whereby when said selected areas of said bistable switch are in the high conductivity state the applied voltage serves to maintain the high conductivity state so that the electric field between said contact means and said optically transparent contact means is applied primarily across said visual display means to generate bright visible light at said selected areas.

Claim 10

A storage tube of the type including an evacuated envelope, an electron gun disposed at one end of said envelope for projecting an electrOn beam carrying signal, an electro-optical transducer disposed at the other end of said envelope for receiving said beam and being responsive thereto to provide and form a display on a face of said envelope adjacent thereto, said electro-optical transducer comprising, a bistable switch for switching an electrical signal applied on the electron gun side of said electro-optical transducer, a plurality of electrically conductive areas on said bistable switch for application of an electrical potential for causing said bistable switch within the adjacent bistable switch body to transition from a low conductivity to a high conductivity state responsive to signals of predetermined magnitude carried by said electron beam and so that said bistable switch is maintained in said high conductivity state by an electric field of predetermined magnitude resulting from said electrical potential applied thereacross, means for providing a visual display of the type which emits light responsive to an electric field of predetermined magnitude applied thereacross formed as a layer having one face electrically connected with one face of said bistable switch and the other face disposed to emit light at the face of said envelope, contact means applied to the other face of said bistable switch forming an ohmic connection to said other face, and optically transparent contact means applied to the other face of said means for providing a visual display to form ohmic connection thereto, whereby a voltage up to 200 volts can be applied across said bistable switch and said visual display layer, whereby when said selected areas of said bistable switch are in the high conductivity state the applied voltage serves to maintain the high conductivity state so that the electric field between said contact means and said optically transparent contact means is applied primarily across said visual display means to generate bright visible light at said selected areas.

Claim 11

A storage tube as in claim 8 wherein said plurality of electrically conductive areas are formed on the one face of said bistable switch, thereby forming a high density array of discrete switches being individually actuated by said electron beam, so that said means for providing a visual display presents an image resolution which is better than that which may be detected by the unaided eye.

Claim 12

A storage tube as in claim 9 together with an opaque insulating layer disposed between said plurality of electrically conductive areas and said one face of said means for providing a visual display.