Abstract:
A middle-infrared image intensifier including an image-forming microchannel plate having an input face with a photoconductor material that is activated by middle-infrared radiation, means for flooding electrons to a region adjacent to the input face of the photoconductor, an electron sensitive light emitting screen positioned to receive electrons from the output face of the microchannel plate, and means for activating the microchannel plate to multiply electrons in channels of the microchannel plate having middle-infrared radiation incident thereon.
Abstract:
An improved electron discharge device comprises an evacuated envelope having therein a photoemissive cathode for providing photoelectrons in response to radiation incident thereon, an electron multiplier, including a primary dynode spaced from the cathode, and a focusing assembly disposed between the cathode and the multiplier. A thermionic electron control plate is disposed between the focusing assembly and the multiplier to prevent thermionic electrons from the focusing assembly from impinging on the primary dynode, while permitting the passage of photoelectrons to the primary dynode. The control plate overlies the primary dynode and is contiguous therewith.
Abstract:
An electron tube having an evacuated envelope includes therein an insulating substrate with a photoemissive cathode thereon. The cathode comprises a plurality of discrete substantially isolated photoemissive regions. A plurality of spaced apart conductive strips are disposed on the substrate and interconnect each of the photoemissive regions.
Abstract:
A photomultiplier tube comprises an evacuated envelope having a photoemissive cathode formed on an interior surface of the envelope. An evaporator support assembly is attached to a dynode assembly in such a manner as to align and precisely locate the dynode assembly with respect to the interior wall surface of the tube. The evaporator support assembly provides a structure for attaching an alkali source within the tube in a manner which guarantees mechanical and electrical reproducibility. The evaporator support structure also includes a structure for making contact to the photocathode of the tube.
Abstract:
An electron discharge tube comprises an evacuated envelope, a photocathode within the envelope and a primary dynode having an active portion substantially coplanar with the photocathode. The active portion of the dynode has an oxide secondary emitting surface. A substantially uniform layer of an alkali antimonide compound is formed on substantially all of the oxide secondary emissive surface of the dynode.
Abstract:
A gas electron multiplier (GEM), used to track cosmic ray muons, can have readout electrodes oriented in a helical pattern so that it can fit inside a narrow aperture borehole. The helical orientation of the readout electrodes provides for high spatial resolution and yet is cost effective to manufacture. The GEM can have an insulation layer, a plurality of conduction layers and an inner layer comprising a plurality of helical conductive stripes extending between two ends of the GEM.
Abstract:
A channel electron multiplier having a high aspect ratio and differential coatings along its channel length is disclosed. The elongated tube has an input end, an output end, and an interior surface extending along the length of the tube between the input end and the output end. The channel electron multiplier also has first and second conductive layers formed on the interior surface of the tube. The first conductive layer is selected to provide a first electrical resistance, a first electron emission characteristic, or both, and the second conductive layer is selected to provide a second electrical resistance, a second electron emission characteristic, or both. A method of making a channel electron multiplier having two or more different conductive layers is also disclosed.
Abstract:
A scalable vacuum photosensor configured to simplify mass production with a housing having an evacuated first side at an ultrahigh vacuum and a second side which does not require high vacuum. The first side of the device is sealed to a base plate, having a central electron readout element, using an oxide-free sealing technique, with the deposited sealing areas serving as high voltage throughputs from the first to second sides. A conductive photocathode layer on the transparent first side converts photons to photoelectrons and concentrates the photoelectrons upon the readout. The first and second sides together form an electrostatic lens for accelerating and focusing photoelectrons upon the readout, preferably having a scintillator which generates secondary light measured by an optical detector in the second side of the housing.
Abstract:
Disclosed are devices, systems, and methods are disclosed that include: (a) a first material layer positioned on a first surface of a support structure and configured to generate secondary electrons in response to incident charged particles that strike the first layer, the first layer including an aperture configured to permit a portion of the incident charged particles to pass through the aperture; and (b) a second material layer positioned on a second surface of the support structure and separated from the first layer by a distance of 0.5 cm or more, the second layer being configured to generate secondary electrons in response to charged particles that pass through the aperture and strike the second layer, where the device is a charged particle detector.
Abstract:
The invention relates to an electron multiplying structure for use in a vacuum tube using electron multiplying, the electron multiplying structure comprising an input face intended to be oriented in a facing relationship with an entrance window of the vacuum tube, an output face intended to be oriented in a facing relationship with a detection surface of the vacuum tube, as well as an ion barrier membrane for shielding off stray ions.The invention also relates to an vacuum tube using electron multiplying having a photocathode capable of releasing electrons into said vacuum chamber when exposed to light, electric field means for accelerating said released electrons from said photocathode towards an anode spaced apart from said photocathode in a facing relationship, as well as an electron multiplying structure according to the invention disposed in said vacuum chamber between said photocathode and said anode.The invention also relates to an ion barrier membrane for use in a vacuum tube and/or an electron multiplying structure according to the invention.It is an object of the invention is to provide an improved electron multiplying structure having an improved performance in term of shielding capabilities against stray ions and reduced loss of emitted electrons. For this purpose, the electron multiplying structure according to the invention is characterized in that said ion barrier membrane is composed of at least one atomic layer containing graphene.