Abstract: A color image intensifier device includes an evacuated envelope with an input window for receiving incident light from the environment. A photocathode is deposited upon the interior surface of the envelope of the input window for converting the incident light into a photoelectron signal. A phosphor layer, emitting several wavelengths approximating white light when struck by and amplified by an intensified photoelectron signal, is deposited upon an interior surface of the envelope proximate an output window to convert the amplified signal into a visible light output image projected from the intensifier.

Abstract: A night vision device enhancement wherein occurrence of a bright object in an input scene of the night vision device is precluded from adversely affecting reproduction of adjacent low radiance level portions of the input scene. By optically limiting or excluding bright object input scene portions from the night vision device input field the disclosed system precludes both image intensifier-related effects, effects such as blooming and current saturation, and also precludes automatic gain control-related effects such as full-field sensitivity decrease based on the bright object. Plural embodiments of the system are disclosed, embodiments based on bright object attenuation by both yet to be developed photo active materials such as photochromics and embodiments which use present state of the art liquid crystal materials and accompanying electronics. Military and non-military uses of the improved night vision device are contemplated.

Abstract: Methods and apparatuses for high-speed control of lamp intensity and for high-speed optical data communication are disclosed. In particular embodiments, an arc, plasma or halogen lamp is provided with the ability to change wavelengths and/or intensities at high rates (up to 10 gigahertz) by maintaining materials which may be solid or liquid under typical lamp operation or storage conditions in the vapor state. This method and apparatus is particularly applicable to microscopy and high-speed optical data communication, particularly at wavelengths in the visible and ultraviolet spectra.

Abstract: This image tube converts irradiated electrons into fluorescence by irradiating electrons converted from a light beam by a photocathode onto a YAG crystal member. Since the YAG crystal member is a single unitary solid, the fluorescence generated on the input surface of the YAG crystal member contains no fixed pattern noise.

Abstract: A segmented photomultiplier tube having an electrode which, in its higher part acts as a focusing electrode for distributing photo-electrons on both sides of an axial plane, while in its lower part forming a collection cage, the photo-electrons undergo a first multiplication at the portions of the lateral walls, which are folded towards the axial plane. Apertures in a median plate of the electrode are covered by a highly transparent grid. The electrode is completed by a central partition which extends along the median plate just to the proximity of an input dynode of a laminated multiplier. A bar having a small cross-section may be provided, centered on the axial plane and receiving a potential near the potential across the photocathode. A plurality of these tubes can be arranged in a mosaic pattern for mapping luminous events.

Abstract: The photocathode according to this invention is characterized in that an aluminium thin film is formed on a substrate, and then an antimony thin layer is deposited directly on the aluminium thin film and is activated by an alkali metal. It is especially preferable that the antimony thin layer is deposited in a thickness of 15 .mu.g/cm.sup.2 to 45 .mu.g/cm.sup.2 and is activated by an alkali metal. Such reflection-type photocathode is applicable to photomultipliers. Among functions which are considered to be done by the Al film. which is in direct contact with the Sb layer, a first one is to prevent the alloying between the Sb layer and the substrate (e.g., Ni), and a second one is to augment a reflectance of light to be detected.

Abstract: A two-dimensional radiation detecting method and apparatus for converting incident radiation in a two-dimensional distribution into electric signals. The apparatus includes a target structure and an electron beam scan mechanism. The target structure has a fluorescent element, transparent electrodes in stripes and a photoconductive film laminated in the stated order on a substrate. The electron beam scan mechanism has a plurality of linear cathodes, backing electrodes for taking electron beams from a selected linear cathode, a vertically converging electrode, vertically deflecting electrodes, accelerating electrodes and a decelerating electrode. The electron beam scan mechanism simultaneously projects the electron beams distributed horizontally to one horizontal line on the photoconductive film, and then shifts the electron beams vertically, to read a two-dimensional distribution of potentials on the photoconductive film.

Abstract: An image intensifier apparatus of this invention comprises a photocathode for converting a first optical image to corresponding photoelectrons, a microchannel plate for multiplying the photoelectrons, impressed with a voltage at both ends thereof, and a fluorescent screen for converting the photoelectrons multiplied in the microchannel plate to a second optical image, emitting the second optical image to an image pickup device. Resistance of the microchannel plate is greater than or equal to 2.8.times.10.sup.15 G.OMEGA. and less than or equal to 2.8.times.10.sup.16 G.OMEGA. per channel.

Abstract: Shock resistant microchannel plate assemblies incorporating stacked or cascaded microchannel plates, and to methods of their use are disclosed. High-output amplification tubes of the photomultiplier type, or of the image intensifier type, having a plurality of sequentially arranged, or cascaded, electron multiplier microchannel plates are also disclosed. More particularly the present invention relates to a high output photomultiplier tube or image tube having cascaded microchannel plates radially constrained by an annular insulating ring. In another aspect of the present invention image intensifier tubes or photomultiplier tubes may include a tapered ceramic high voltage stand-off. Moreover, a method of making such tubes is also disclosed.

Abstract: An improved photocathode (12) and image intensifier tube (10) are disclosed along with a method for making both the tube (10) and photocathode (12). The disclosed image intensifier tube (10) creates a visible light image (20) from an image emitting photons (22). The tube (10) comprises a photocathode (12) having an indium-gallium-arsenide active layer (26) and an aluminum-gallium-arsenide window layer (28). The photocathode (12) is operable to emit electrons (23) in response to the photons (22). A display apparatus is coupled to the photocathode (12) and is operable to transform the emitted electrons (23) into a visible light image (24). An embodiment of the invention is capable of detecting 1.06 .mu.m radiation.

Abstract: An X-ray image intensifier has a vacuum envelope consisting of glass, and an input window consisting of aluminum and having a sectional meridian radius of curvature which increases from the central portion of the input window to the peripheral portion thereof is arranged on the input side of the vacuum envelope with a metal holding ring and a Kovar ring. An input phosphor surface is arranged adjacent to the inner surface side of the input window, and an X-ray image incident through the input window is converted into a photoelectron image. In order to minimize an influence caused by scattering of X-rays or .gamma.-rays incident through the input window, an input substrate is brought as close to the input window as possible. A coaxial cylindrical focusing electrode and an annular focusing electrode are arranged on the side wall in the vacuum envelope, and an anode is arranged on an output end side.

Abstract: A collimator is included in a microchannel plate image intensifier (MCPI). Collimators can be useful in improving resolution of MCPIs by eliminating the scattered electron problem and by limiting the transverse energy of electrons reaching the screen. Due to its optical absorption, a collimator will also increase the extinction ratio of an intensifier by approximately an order of magnitude. Additionally, the smooth surface of the collimator will permit a higher focusing field to be employed in the MCP-to-collimator region than is currently permitted in the MCP-to-screen region by the relatively rough and fragile aluminum layer covering the screen. Coating the MCP and collimator surfaces with aluminum oxide appears to permit additional significant increases in the field strength, resulting in better resolution.

Abstract: An imaging tube having a fiber optic plate (FOP) as an output faceplate. On one surface of the FOP within an evacuated envelope is deposited a first transparent conductive layer. On the first transparent conductive layer is deposited a fluorescent layer. On the fluorescent layer is deposited a metal-back electrode. On the other surface of the FOP outside the evacuated envelope is deposited a second transparent conductive layer. The first transparent conductive layer and the metal-back electrode are electrically connected so that an electrical field is not developed across the fluorescent layer when the metal-back electrode is applied with a high positive voltage and the second transparent conductive layer is grounded. Therefore, even if leakage currents flow through the FOP, electric charges impinging upon the first transparent conductive layer will not cause the fluorescent layer to generate noise spots.

Abstract: A night vision visor system that is compact, light in weight, and ejection-safe, and which provides the user with an unobstructed peripheral field of view and other structural and operational advantages. The night vision visor system includes a visor adapted to be mounted to a helmet to be worn by a user and to be positioned substantially in front of the user's face, and a night vision imaging apparatus mounted to the visor for receiving incoming visible and/or infrared light from an object, for converting the incoming light to an intensified visible light, and for presenting the intensified visible light to an eye of the user. The night vision imaging apparatus includes first and second night vision imaging devices mounted in openings in the visor and movable with the visor between a down position in front of the user's face when is use and a raised position away from the user's face when not in use.

Abstract: An improved electrostatically-focused image intensifier tube, and a night vision device having such a tube, is substantially free of the spurious bright spots generally known as "PC Flash". The improved image intensifier tube includes an insulator which resists emission of electrons into the interior cavity of the tube, or a structure to capture such emitted electrons before they can fall into a microchannel plate of the tube and cause the PC Flash. A method of making such an image intensifier tube is also disclosed.

Abstract: A night vision device with improved user safety includes a head gear support structure which suspends a night vision viewer relative to the head and eyes of the user. The head gear includes a flip up mount allowing the user to flip the night vision viewer up and out of the user's line of sight for an unobstructed natural view of the environment. In order both to save battery power, and to prevent the user from inadvertently revealing his position by forgetting to turn off the night vision viewer before flipping it up, the support structure includes a magnetic flux source cooperable with a magnetically-responsive switch of the night vision viewer to maintain the viewer turned on only when the viewer is in its use position. When the viewer is flipped toward its upward position, the switch of the viewer is carried out of magnetic association with the flux source so that the viewer shuts off.

Abstract: The present invention is a vacuum housing for an image intensifier tube, wherein the vacuum housing is unistructurally formed from a dielectric material and retains a photocathode, microchannel plate (MCP) and anode within an evacuated environment. The vacuum housing is manufactured as a single, solid component, thereby having no seams which may leak and compromise the evacuated environment. The various electrically operative elements of the photocathode, MCP and anode engage separate metalized surfaces formed within the vacuum housing. The electrically operative elements of the photocathode, MCP and anode within the vacuum housing are empowered by coupling the various metalized regions to sources of electrical potential external for the evacuated environment.

Abstract: An exit section of an X-ray image intensifier tube, including an the exit phosphor screen, exit window and basic optical system, is optimized so as to achieve a high light yield, low optical aberration and a high resolution. The exit window notably has a pre-compensation geometry for curvature of the image plane of the basic optical system, or the exit window an interference filter, or the exit phosphor layer contains a layer of a comparatively slow phosphor in addition to a layer of a customary phosphor in order to achieve noise-suppressing image integration.

Abstract: An electron gun is modulated by an optoelectronic switching device. This switching device comprises a modulated light source and at least one GaAs or Si solid-state optoelectronic switch, this switch being non-conductive when not illuminated and conductive when illuminated by the modulated light source; the device also includes components to transmit the light from the source to the switch(es). In one embodiment, the modulated light source is a laser and in a second embodiment the source is a continuous source externally modulated by a mechanical or electrooptical device. The optoelectronic switching device is connected between a high-voltage source and the cathode of an electron gun, thus modulating the cathode.The invention is particularly applicable to microwave electron tubes.

Abstract: An electron emission element comprises a P-type semiconductor substrate and electrodes formed on both ends of the semiconductor substrate. A voltage is applied between said electrodes. The P-type semiconductor substrate is irradiated with light to emit the electrons, generated in the P-type semiconductor substrate by photoexcitation, from an electron emitting face at an end of the P-type semiconductor substrate.

Abstract: A image intensifier tube, having its brightness curve corrected in a simple way. The image intensifier tube comprises an input window (3), and an output window (4) at which the brightness is measured. The output window (4) bears a device for the attenuation of light (20), the opacity of this device being greater in a central zone (0) than it is towards the edges (21).

Abstract: Night vision apparatus, particularly night vision goggles, having a wide field of view. The apparatus includes an objective optical system having a selected field of view for collecting visible and/or infrared light from an object to be viewed and for providing an input image of the object; image intensifying and magnifying means for receiving the input image and for providing a visible, intensified and magnified output image of the input image, and an eyepiece optical system for receiving the visible, intensified and magnified output image and for presenting a visible intensified image of the object to an eye of a user at unity magnification. The image intensifying and magnifying means preferably comprises an image intensifier tube having a fiber optic bundle beam expander therein. The image intensifying and magnifying means permits the eyepiece optical system to have a longer focal length and, hence, to provide greater eye relief than would otherwise be possible.

Abstract: Contact device (10) for the photocathode (11) of photoelectric tubes is produced by a metallic deposit on a substrate (12) intended to receive the photocathode. According to the invention, the contact device (10) is formed by narrow conductive contacts (20) deposited on the useful area (21) of the substrate (12).

Abstract: Apparatus for high speed analog data recording utilizing a new tube design (referred to herein as a photonic cathode ray tube) is presented. The photonic cathode ray tube includes a flat photocathode, a small aperture electron lensing system, a set of deflection plates and a phosphor screen.

Abstract: In an image intensifier tube comprising a photosensitive layer an insulating wall portion is coated with a layer of chromium oxide which is deposited in the form of a chromium nitrate layer which is subsequently baked at a temperature of approximately 525.degree. C. A thin, suitably adhesive, uniform and transparent coating layer having a comparatively high resistance value is thus achieved.

Abstract: A luminescent screen includes a screen plate containing a substance capable of emitting luminescent light in response to stimulating light applied thereto, and a regular array of convexes on one surface of the screen plate for trapping emitted luminescent light that is directed into the screen plate and for directing the trapped luminescent light toward a display surface of the screen plate. The brightness of the display surface is therefore increased.

Abstract: Contact device for the photocathode of photoelectric tubes includes a metallic deposit of narrow conductive contacts on the photocathode substrate. The device is useful in image intensifier tubes and fast slot scanning cameras.

Abstract: An image intensifier tube having a photocathode, a microchannel plate and an anode. The anode includes a lens element with a phosphor screen deposited thereon as an output window. The lens element may take the form of either a plano-convex or plano-concave element and has either a spheric or aspheric curved surface. In a modified version a plano glass element is affixed to the plano surface of the lens element. Methods of forming the tube with the lens element are at the time the finished tube is assembled in the intensifier device or at the time the tube is constructed.

Abstract: Metal parts of an image intensifier tube which are exposed to a high voltage are coated with a layer of aluminum phosphate glass in order to preclude local discharge phenomena; the aluminum phosphate glass can be deposited in a thin, uniform layer already at a comparatively low flow temperature. Because the layer is thin, it is not necessary to take into account differences in coefficients of expansion, so that a high degree of freedom is achieved as regards the choice of materials for the metal parts.

Abstract: The entrance screen in an X-ray image intensifier includes an intermediate layer of a material which selectively absorbs photon energy. As a result, the speed of the photo-electrons is substantially reduced, thus improving the imaging. By introducing a radial variation of the absorption in the intermediate layer, vignetting-compensation can also be realized without substantial loss of sensitivity and resolution for the central portion of the tube. The resolution at the periphery of the tube can thus be substantially improved.

Abstract: An image intensifier tube has a faceplate formed of optical material. The outer surface of the faceplate has light receiving and light transmitting surfaces and a layer of a reduced metal oxide material for reducing stray light which is transmitted into the faceplate and reflected off of internal surfaces thereof. The layer has a blackened appearance and is formed by reducing the metal oxide of the faceplate material with hydrogen at a predetermined pressure and temperature to cause the blackening to reach a depth sufficient to reduce transmission of stray light therethrough.

Abstract: A photo electric conversion tube in which a translucent photocathode surface is provided inside of an incident light window. The incident light window is made of glass plate and an optical fiber plate bonded to at least part of the glass plate or just the optical fiber plate on the photocathode surface. The optical fiber plate contains fibers which are inclined at an angle to the photocathode surface.

Abstract: An optical system of a television camera comprises, according to the invention, arranged in the direction of the light flux on one optical axis, an objective composed of n elements and a faceplate of a television tube, a light-sensitive layer being located on the last, in the direction of the light flux, surface of said faceplate. The last, in the direction of the light flux, element of the objective has an optical power other than zero and is made as, for example, a concave-flat lens having its concavity facing the object. This last element is the faceplate (3) of the television tube (4).

Abstract: An apparatus continous imaging apparatus comprising a camera portion and an image receiving portion, Specifically, the image pickup portion comprises an image pickup tube that deflects and scans electron beams and allows electron signals correponding to one pixel or a one-dimensional array of pixels to be converted successively and continuously to time-series light signals. The image receiving portion comprises means that converts to electron beams the time-series light signals transmitted from the pickup tube through at least one optical fiber and which reproduces an image by deflecting the electron beams in synchronism with the camera portion.

Abstract: This invention relates to an X-ray image intensifier for intensifying and reproducing an image of an object, by use of X-ray and the like. An evacuated envelope of the image intensifier is constituted by a cylindrical glass body having an open end and a closed end, an X-ray input window covering the open end of the body, and a support ring for providing a hermetical seal between the body and the window at the open end. The window is constituted by a domed portion which expands outwardly from the evacuated envelope, a flange portion which is formed around the peripheral edge of the window and has a flat bonding surface which extends perpendicular to the axis of the evacuated envelope, with a curved portion forming a transitional area between the domed and flange portions. The support ring is bonded to the flange portion, at the flat bonding surface, and has a smaller inner diameter than the outer diameter of the curved portion.

Abstract: The disclosed charge transfer signal processor includes a vacuum housing having an input face and a output face, a 2-D electromagnetic input means cooperative with said input face for providing a 2-D input electronic charge signal within the vacuum housing, transfer means for imaging the 2-D input electronic charge signal in a region of the vacuum housing proximate the vacuum housing output face, and charge feedthrough means coupled to the vacuum housing output face for transferring the imaged 2-D electronic charge signal externally to the vacuum housing. In one embodiment, the charge transfer signal processor is operable as a Gen-I charge transfer amplifier. In another embodiment, a microchannel plate assembly is dThis invention was made with Government support under Contract F19628-84-C-0048 awarded by the Department of the Air Force. The government has certain rights in the invention.

Abstract: A method and apparatus for arranging primary optical apparatus to provide a high degree of adaptability to other vision equipment. The primary optical apparatus (10) includes a housing (90) with a number of cavities for holding optical components in alignment with respect to various optical paths. An image intensifier tube (114) is mounted in a cavity (112) disposed in a planar face (70) of the housing (90). The planar face (70) is adapted for mounting to a variety of other optical equipment. A collimator (115) is disposed in a housing cavity (113) and optically aligned between the tube (114) and a dual prism (128, 136). The optical images existing the prisms (128, 136) are redirected through turning mirrors (154, 158) and presented through eyepieces (92) to an observer.

Abstract: Anti-veiling-glare glass input window for an optical device. The window has throughout a shallow surface layer over its peripheral surfaces radiation absorbent free-metal-induced color centers. A method for preparation of such a window, which is particularly suited to be used as an input window for an image intensifier, involves preshaping the window from clear glass and forming color centers in a shallow surface layer over at least the peripheral surfaces of the window. If the clear glass contains reduceable metal oxides the color centers are formed by subjecting at least the peripheral surfaces of the clear glass to a reducing atmosphere at a temperature high enough to cause the reducing atmospheres reducing component to diffuse into a shallow surface layer of the window and to reduce the metal oxides to free metal atoms.

Abstract: New fiber optic elements and a new microchannel plate for proximity focus image intensifier tubes and a method for making them are provided. Higher resolution is provided at the center of the field of view by the use of graded fiber and channel sizes and by the use of convex and concave surfaces in proximity focus.

Abstract: A streak camera for measuring light rays which vary at high speed comprises a refractive member for receiving and bending a light beam to a substantially slit-shaped form, and a streak tube assembly for forming a streak image representative of time variations of the slit-shaped beam supplied to the tube assembly from the refractive member. A glass rod with a unidirectional refractive index distribution is preferably used as the refractive member. The refractive index of the refractive member varies in parallel with the direction of deflection of the streak tube assembly.

Abstract: An imaging tube particularly useful in providing a visible image corresponding to an incident infrared image in which a reflective photocathode is used to provide an electron image corresponding to the infrared image, and in which the incident image rays and the ultimate image rays move along different directions.

Abstract: A stereo imaging apparatus using a single image intensifier is comprised of an input responsive to incident radiation corresponding to first and second views. An image intensifier is responsive to the input for simultaneously intensifying the incident radiation corresponding to the first and second views. An output is provided for the intensified radiation.

Abstract: A color separation filter arrangement for an image intensifier having separate blue, green and red filters which respectively have pass bands for visible blue light and its second order wavelengths, visible green light and its second order wavelengths, and visible red light. The blue, green and red filters are interposed individually in succession in the path of incident visible light and infrared energy to the photocathode of the image intensifier. Use of this color separation filter produces a relatively high signal-to-noise ratio at the output of the image intensifier when it is used under night sky illumination.

Abstract: An image intensifier tube and a method of making same are disclosed wherein veiling glare caused by the amplification of off axis light is reduced. Included is a non-reflective, near infrared light absorbing first layer formed on the face plate of the tube adjacent any surface at which off-axis light could otherwise be reflected to the photoemissive device associated with the face plate and an electronically conductive second layer formed on top of the first layer. Such coatings are preferably formed by sputter deposition.

Abstract: Photoelectric detection device comprising a vacuum chamber provided with a window having a substrate which bears a photocathode on the internal surface of the vacuum chamber is sensitive to incident light radiation between a short wavelength .lambda..sub.1 bottom threshold and a longer wavelength .lambda..sub.2 upper threshold. Electrons emitted by the photocathode are focused, accelerated and deflected by electronic means to deliver signals or an image representative of luminous events projected onto the photocathode. Window is provided with at least one light filter which determines the wavelength range for which the detection device is operational, eliminating wavelengths greater than a wavelength .lambda..sub.f such that .lambda..sub.1 <.lambda..sub.f <.lambda..sub.2. This light filter can be a pass-band filter which also eliminates wavelengths lower than a wavelength .lambda.'.sub.f such that .lambda..sub.1 <.lambda.'.sub.f <.lambda..sub.f.

Abstract: A so-called "solar-blind" photomultiplier tube includes an envelope having a sidewall and an input faceplate formed from an ultraviolet transmitting filter. A photoemissive cathode is disposed within the envelope for providing photoelectrons in response to radiation incident thereon. The cathode has an intrinsic responsivity extending from the near-ultraviolet portion through the visible portion of the electromagnetic spectrum; however, the filter faceplate transmits only the ultraviolet portion of the spectrum to the photoemissive cathode. The combination of the filter faceplate and the photoemissive cathode therefore limits the tube to a responsivity within the wavelength range of about 300 to less than 400 nanometers.

Abstract: An image intensifier tube and a method of making same are disclosed wherein veiling glare caused by the amplification of off-axis light is reduced. A face plate is formed from a fused assembly of a glass rod having a low reflective, light absorbing layer thereon, a cladding tube and a jacket tube. The fused assembly is then cut into wafer-shaped slices and the ends polished.

Abstract: An electron bombarded silicon spatial light modulator in which electrons leaving a microchannel plate amplifier are accelerated to penetrate a silicon photodiode forming electron-hole pairs therein and resulting in significant current gains.

Abstract: A photocathode arrangement comprises a body of semiconductor material, such as gallium arsenide which is bonded to a fiber optic face plate. A thin anti-reflection coating of silicon nitride is positioned between the body and the plate and forms an integral part of the bond. The properties of the glasses from which the fiber optic face plate is made are carefully chosen to minimize crystal dislocations which can be introduced into the body of gallium arsenide when it is bonded to the face plate. Such crystal dislocations can seriously impair the performance of the photocathode. It has been found that it is advantageous to use a glass having an annealing temperature of about 575.degree. C. or less. Because of high temperature processing steps, its softening temperature must be about 680.degree. C. or greater. The photocathode arrangement so formed is intended to constitute the input port of an image intensifier.

Abstract: An image intensifier tube and a method of making same is disclosed wherein veiling glare caused by the amplification of off axis light is reduced. Included is a colored, low reflective, light absorbing layer formed in the face plate of the tube adjacent any surface at which off axis light could otherwise be reflected to the photoemissive device associated with the face plate.