Abstract: A device configured to convert or amplify a particle, the conversion or amplification being reliant on the impact of a particle on a surface of the device causing emission of one or more secondary electrons from the same surface. The device includes a carbon-based layer capable of secondary electron emission upon impact of a particle. The surface may be used to convert, for example, an ion into an electron signal, or an electron signal into an amplified electron signal, such as in conversion or amplification dynodes.

Abstract: Components of scientific analytical equipment, and particularly to methods for extending the operational lifetime or otherwise improving the performance of dynodes used in electron multipliers. The method includes: (i) increasing the secondary electron yield of a dynode and/or (ii) decreasing the rate of degradation of electron yield of a dynode, by exposing a dynode electron-emissive surface to an electron flux under conditions causing electron-impact induced removal of a contaminant deposited on the dynode electron-emissive surface. The conditions may be selected such that the electron-mediated removal is enhanced relative to a contaminant deposition process so as to provide a net decrease in the rate of contaminant deposition and/or a decrease in the amount of contaminant present on the dynode electron-emissive surface.

Abstract: An apparatus for amplifying an electron signal caused by the impact of a particle with an electron emissive surface. The apparatus includes: a first electron emissive surface configured to receive an input particle and thereby emit one or more secondary electrons, a series of second and subsequent electron emissive surfaces configured to form an amplified electron signal from the one or more secondary electrons emitted by the first electron emissive surface, and one or more power supplies configured to apply bias voltage(s) to one or more of the emissive surfaces. The bias voltage(s) is sufficient to form the amplified electron signal. The apparatus is configured such that the terminal electron emissive surface(s) of the series of second and subsequent electron emissive surfaces draw a higher electrical current than that of the remainder electron emissive surface(s). The apparatus may be used as part of detector in a mass spectrometer, for example.

Abstract: Components of scientific analytical equipment and to complete items of analytic equipment. An apparatus and methods useful for detecting an ion in mass spectrometry applications are provided. The apparatus may include an electron multiplier having a high sensitivity and low sensitivity sections, or the combination of an electron multiplier with a separately powered conversion dynode (and particularly a high energy conversion dynode), or the combination of a conversion dynode that is physically incorporated within or about an electron multiplier.

Abstract: An apparatus for amplifying an electron signal caused by the impact of a particle with an electron emissive surface. The apparatus includes: a first electron emissive surface configured to receive an input particle and thereby emit one or more secondary electrons, a series of second and subsequent electron emissive surfaces configured to form an amplified electron signal from the one or more secondary electrons emitted by the first electron emissive surface, and one or more power supplies configured to apply bias voltage(s) to one or more of the emissive surfaces. The bias voltage(s) is sufficient to form the amplified electron signal. The apparatus is configured such that the terminal electron emissive surface(s) of the series of second and subsequent electron emissive surfaces draw a higher electrical current than that of the remainder electron emissive surface(s). The apparatus may be used as part of detector in a mass spectrometer, for example.

Abstract: An apparatus for manipulating the trajectories of moving charged particles. The apparatus includes a grid of laterally spaced side by side elongate elements and means defining a path for charged particles to traverse the grid. The grid is supported and configured for application of a voltage gradient between and/or along the elongate elements, whereby to manipulate the trajectories of charged particles that traverse the grid. A method of manipulating the trajectories of moving charged particles is also disclosed.

Abstract: An apparatus 10 for manipulating the trajectories of moving charged particles. The apparatus includes a grid 14 of laterally spaced side by side elongate elements 16 and means 18 defining a path for charged particles to traverse the grid. The grid is supported and configured for application of a voltage gradient between and/or along the elongate elements, whereby to manipulate the trajectories of charged particles that traverse the grid. A method of manipulating the trajectories of moving charged particles is also disclosed.

Abstract: An electron multiplier detector includes cathode structure defining a plurality of spaced co-planar impact surface segments on which particles impact. These surface segments each have a finite probability of generating at least one electron for each impacting particle having predetermined characteristics. The detector further includes respective sets of electron multiplication dynode segments associated with the impact surface segments, the sets being arranged as substantially parallel arrays extending behind the impact surface segments, and respective means for generating electrostatic and magnetic fields in a space extending from the impact surface segments past the dynode segments, whereby respective streams of electrons cascade and multiply successively along the arrays of dynode segments. Collector structure is provided to receive and detect the streams of electrons downstream of the last dynode segments in the arrays.

Abstract: Electron focussing apparatus includes a cathode plate defining an impact surface on which particles impact, which surface has a finite probability of generating at least one electron for each impacting particle having predetermined characteristics. The apparatus also has an electron receiving element, and respective means for generating electrostatic and magnetic fields in a space extending from the impact surface to the electron receiving element. The means for generating the electrostatic and magnetic fields are configured whereby the E/B2 ratio adjacent the electron receiving element is smaller than adjacent the impact surface, whereby to decrease the radius of curvature of the electron trajectories adjacent the electron receiving element relative to adjacent the impact surface and to thereby focus the electron trajectories in at least one dimension.

Abstract: Electron focussing apparatus includes a cathode plate defining an impact surface on which particles impact, which surface has a finite probability of generating at least one electron for each impacting particle having predetermined characteristics. The apparatus also has an electron receiving element, and respective means for generating electrostatic and magnetic fields in a space extending from the impact surface to the electron receiving element. The means for generating the electrostatic and magnetic fields are configured whereby the E/B2 ratio adjacent the electron receiving element is smaller than adjacent the impact surface, whereby to decrease the radius of curvature of the electron trajectories adjacent the electron receiving element relative to adjacent the impact surface and to thereby focus the electron trajectories in at least one dimension.