Abstract: Scanning electron microscopy apparatus employing a detector to detect emission of electrons resulting from the impingement of electrons of an electron beam on an object being viewed, the apparatus including an electron beam source providing the electron beam, a magnet providing a magnetic field to direct the electron beam to the object, a first microchannel plate having a first hole through it aligned with the electron beam, a first surface directed toward the electron beam source for receiving low energy electrons that have been emitted from the object and directed through the hole by the magnetic field, a second surface on the opposite side of side first microchannel plate for discharge of multiplied electrons, and a first anode facing the second surface, the first anode being positioned to collect electrons discharged from the second surface.

Abstract: A secondary electron multiplier having a Venetian blind dynode structure for use in a photomultiplier tube or the like. The dynode structure includes first and second dynodes being vertically disposed transverse to each other in that the geometrically transparent part of the first dynode is aligned with a portion of the geometrically opaque part of the second dynode corresponding to a width dimension defined from the lower end of the second dynode, and the voltages applied to the dynodes are specially configured to provide a sufficient energy to the dynodes for secondary electron mulitplication.

Abstract: An electron multiplier device consists of an insulating substrate having, a plurality of through-holes, a first secondary electron emission layer and a second secondary electron emission layer or a conductive layer, and a DC electric field is applied to the first secondary electron emission layer with respect to the second latter secondary electron emission layer or conductive layer.

Abstract: A channel secondary electron multiplier has a mechanically sturdy body made of metal or ceramic material. The body forms an internal multiplier channel having a curved, e.g. helical main portion and a funnel shaped entrance end. A resistive layer forming a secondary electron emissive surface is provided on the inner wall of said channel inclusive that entrance end. The secondary electron emissive resistive layer in said funnel shaped entrance end has the form of a spiral-shaped band or stripe having a width which is preferably at least approximately equal to the circumferential dimension of the main portion of said channel. The body has a thermal coefficient of expansion which is at least 15% larger than the thermal coefficient of expansion of said layer, to maintain said layer under compression.

Abstract: A channel plate electron multiplier of the discrete dynode type formed from conductive sheets which are stacked in closely spaced relation. Each sheet is perforated with apertures which are aligned to form electron multiplying channels. The apertures in each sheet have input and output and cross sections which are approximately the same size and a concave shaped inner surface profile which causes a majority of electrons to strike the inner surface close to the output end, whereby the gain of the multiplier is increased.

Abstract: An electron discharge device includes an evacuated envelope having therein a photocathode, an anode and an electron multiplier. The electron multiplier comprises a plurality of dynodes having a nickel substrate, an exposed surface of which has a base layer of antimony sensitized with the vapors of a plurality of alkali metals. At least one Nichrome dynode, substantially devoid of secondary emissive material is disposed adjacent to the anode. The Nichrome dynode reduces and stabilizes the anode sensitivity and gain of the device.

Abstract: Particle detector comprising a vacuum envelope in which there are provided a thin planar target made from a material which can emit secondary electrons when a given particle of sufficient energy strikes the target and an electron multiplier comprising a plurality of thin planar amplifying plates made from a material able to emit secondary electrons when struck by electrons with a sufficient energy, said plates being parallel to the target and spaced from one another, the secondary electrons emitted by the target and by each of the plates being accelerated by an appropriate potential difference established between the target and the closest plate and between the various plates, wherein the materials forming the target and the amplifying plates are porous.

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 photon-counting detector array utilizes a one-dimensional multiple element anode array is in proximity focus to the last plate of the microchannel array for collecting the electrons generated therein. A specific embodiment has 64 anode elements. A detector system is provided with separate charge amplifiers, and level discriminators for each anode element. The discriminator outputs can be serially read out to a digital computer. Alternatively or additionally, the discriminator outputs are accumulated in counters, and display electronics are provided which can include digital-to-analog converters for forming a display representative of the counts accumulated in each counter, and the total count accumulated in all the counters.

Abstract: An electron emissive surface portion on one of a series of electrodes includes a cross-sectional contour substantially characterized by a superimposed undulating line of curvature which includes a plurality of interconnected arcuate regions.