Abstract:
A light and charged particle image intensifier receives incident image conveying light or charged particles ("incident beam") and provides to data processing and video equipment signals from which the image conveyed by the incident beam can be constructed and displayed. The beam that is being processed includes visible light reflected from objects and X-ray radiation that has been passed through an object such as a human body. The image intensifier includes a scintillator and photocathode unit for converting the incident beam to photoelectrons and a charge-coupled device ("CCD") for detecting the photoelectrons and transmitting to the data processing and video equipment information relating to the quantity or energy level as well as the location of the electrons impinging on the sensing areas of the CCD. From this information, the data processing and video equipment can reconstruct the image conveyed by the incident beam. The sensitivity of the device is increased either by imposing an electric field across the photocathode and the CCD to accelerate the photoelectrons or by placing a micro channel plate ("MCP") between the photocathode and the CCD to increase the number of electrons that impinge on the CCD. Alternately, a silicon diode target can be used instead of a CCD to intercept the electrons and an electron beam gun can be used to detect the location and intensity of the charges created on the target by the impinging electrons. Finally, a grid having a number of windows can be used instead of a CCD or a silicon target to detect the location of the electron streams and a photoanode can detect their intensity.
Abstract:
An evacuated envelope has front and rear walls spaced apart by a plurality of side walls. On the inner surface of the front wall is a cathodoluminescent screen. A magnet structure extends along one of the side walls spaced therefrom and has two spaced poles each of which is parallel to the front wall. The magnet structure generates a uniform magnetic field between the two poles. An electron gun is within the envelope for generating and directing an electron beam into the space between one side wall and the magnet structure. Also included in the device is means for deflecting the electron beam so that it will pass between the poles of the magnet at a plurality of points along the magnet's length. The deflection means maintains a constant angle of incidence at which the electron beam enters the space between the two poles at various points. Means are also included for deflecting the electron beam towards the screen as it emerges from between the magnet poles.
Abstract:
An evacuated envelope has a rectangular display section and a gun section at one edge of the display section. The display section includes front and back walls which are generally rectangular, in closely spaced, parallel relation, and a plurality of spaced, parallel support walls between the front and back walls forming a plurality of parallel channels. At one side of the display section is at least one keying channel which extends parallel to the channels of the display section. The gun section extends across one end of the channels and includes therein gun structure which will direct electrons into the channels. In each of the channels is a beam guide which confines the electrons in a beam and guides the beam along the length of the channel; means for selectively deflecting the electron beam out of the guide toward the front wall at selective points along the guide so that in the display channels the beams will impinge upon a phosphor screen along the inner surface of the front wall; and a scanning deflector which deflects the path of the beam transversely across its channel as the beam passes from the guide to the front wall so that each of the beams in the display channels will scan a portion of the phosphor screen. In the keying channel is means for detecting the position of the beam as it is deflected transversely across the channel along the entire length of the deflected path of the beam.
Abstract:
In the method of exposing a relatively large number of parallel, spaced apart stripe-like areas on the surface of a photo-sensitive member by directing light against such surface through an original photo-mask having a light-permeable pattern comprised of a relatively small number of parallel, spaced apart transparent stripes of lengths substantially smaller than the length of the areas to be exposed, and by effecting repeated relative scanning movements of the photo-sensitive member and photo-mask in the direction of the transparent stripes and relatively shifting the photo-sensitive member and the photo-mask in the direction transverse to the transparent stripes for each of the relative scanning movements so that, upon the completion of the repeated movements, light passing through the light-permeable pattern of the photo-mask will have scanned the desired relatively large number of stripe-like areas to be exposed on the surface of the photo-sensitive member; the transparent stripes of the original photo-mask are formed with respective lengths that decrease progressively from maximum values adjacent the center of the light-permeable pattern, considered in the direction of the relative shifting, to minimum values at the opposite sides of the pattern also considered in the direction of the relative shifting, and each relative shifting is effected through a predetermined distance equal to (1/2.sup.n)W, in which n is an integer and W is the effective width of the light-permeable pattern in the direction of the relative shifting, whereby to minimize variations in the pitch between adjacent exposed stripe-like areas on the photo-sensitive member due to unavoidable variations in the relative shifting of the photo-sensitive member and the original photo-mask.
Abstract:
An electrical field sustained conductivity device is fabricated by successively disposing over a layer of cadmium sulfide a film of metal particles and a composite layer of metal particles in an insulating medium. When a potential is applied across the cadmium sulfide layer, an image may be stored therein by momentarily exposing the layer to electrons or light conveying that image. Such exposure introduces conductivity changes in the cadmium sulfide layer by virtue of the layers deposited on it and the conductivity changes are retained so long as the applied potential is maintained.
Abstract:
The invention provides a photo-conductive target pick-up tube in which light is introduced into the tubular anode electrode on the gun cathode side of the target. The light is introduced evenly around the circumference of the anode, the inner surface of which is roughened to achieve diffused illumination of the rear of the target. In operation of the tube an artificial dark current is obtained which tends to reduce build up and deca
Abstract:
A display system having a cathode ray tube signal generator in which a solid state junction target utilizes a layer of semiconductor material and a layer of dielectric material to form a junction. The signal generator may be of the monoscope type in which portions of the target are masked or it may be of the photosensitive type in which an image is projected onto the target. A signal derived from the signal generator is displayed on a second cathode ray tube.
Abstract:
Improved image storage and display devices of the type which includes a layer of phosphor material which is stimulated to emit light through photoluminescence. The intensity of emitted light is varied by applying an electric field to the phosphor layer. The field may be applied to the phosphor layer by sandwiching the layer between a layer of insulating material and a layer of electrically conductive material and subjecting the insulator to an electron beam. To alter the field strength at selected locations a writing electron beam is focussed on the insulator at these selected locations. In the alternative, the phosphor layer may be covered on one surface with insulation materials forming a charge trap and the phosphor and insulation layers sandwiched between sets of orthognal electrically conductive strips. Selective field alteration is accomplished by X-Y addressing an orthognal pair of conductive strips.
Abstract:
A target for use in an electronic tube is provided on a conductive layer of a support member and it comprises solid dielectric domains adhered to the conductive layer and spaced from one another. The peripheries of the dielectric domains have a random configuration so that the spacing therebetween defines random cracks exposing areas of the conductive layer. The target can also be a metallic mesh having openings of non-regular cell size if the metallic mesh is provided with dielectric thereon which has random cracks therein which exposes areas of the metal.
Abstract:
A ferroelectric ceramic is mounted within a CRT in a ''''strainbiased'''' state, so that it is birefringent. A reflective layer is mounted adjacent the ceramic, and a photoconductive layer is mounted adjacent the reflective layer. With a potential applied across the ceramic-photoconductive layer combination, an image written upon regions of a phosphor target adjacent the photoconductive layer by an electron beam, results in the flow of local charge through corresponding regions of the ceramic, thereby changing the polarization thereat. The flow of polarization charge acts to modulate the birefringence in the ceramic, in accordance with the pattern of the image. A corresponding pattern of brightness is then projected upon an external screen. A ''''scattering mode'''' arrangement is also employed.