A mass spectrometer is described that includes a multipole configured to pass an ion stream, the ion stream comprising an abundance of one or more ion species within stability boundaries defined by (a, q) values. A detector formed by a plurality of dynodes is configured to detect the spatial and temporal properties of the abundance of ions, where each dynode arranged such that it is struck by ions in a known spatial relationship with the ion stream. The detector also includes a plurality of charged particle detectors, each associated with one or more of the plurality of dynodes. A processing system is configured to record and store a pattern of detection of ions in the abundance of ions by the dynodes in the detector.

A mass spectrometer is described that includes a multipole configured to pass an ion stream, the ion stream comprising an abundance of one or more ion species within stability boundaries defined by (a, q) values. A detector formed by a plurality of dynodes is configured to detect the spatial and temporal properties of the abundance of ions, where each dynode arranged such that it is struck by ions in a known spatial relationship with the ion stream. The detector also includes a plurality of charged particle detectors, each associated with one or more of the plurality of dynodes. A processing system is configured to record and store a pattern of detection of ions in the abundance of ions by the dynodes in the detector.

A charge carrier multiplier structure for a light sensor, in particular an ultraviolet light sensor, is described. The charge carrier multiplier structure comprises a dielectric sheet having first and second opposite faces and having an array of holes traversing the dielectric sheet between the first and second faces, at least two photocathodes supported on the first face of the dielectric sheet that are electrically isolated from each other and which define at least two sensing regions, each photocathode having a respective work function and quantum yield and having a respective area and at least one anode supported on the second face of the dielectric sheet.

A light intensifier includes a semiconductor structure to multiply electrons and block stray particles (e.g., photons and/or ions). The semiconductor structure includes an electron multiplier region that is doped to generate a plurality of electrons for each electron that impinges a reception surface of the semiconductor structure, blocking regions that are doped to direct the plurality of electrons towards emissions areas of an emission surface of the semiconductor structure, and shielding regions that are doped to absorb stray particles that impinge the emission surface of the semiconductor structure.

A device (1), such as a detector or imaging device, for detecting ultraviolet light, is described. The device comprises a housing (4) for a chamber. Disposed within the housing is a charge carrier multiplier structure (9) comprising a dielectric sheet (10) having first and second opposite faces (11, 12) and having an array of holes (16) traversing the dielectric sheet between the first and second faces. The device includes a photocathode (13) supported on the first face of the dielectric sheet, having a work function of less than 6 eV. The device includes an anode (14) supported on the second face of the dielectric sheet.