Disclosed herein is a photomultiplier tube (PMT) comprising: an electron ejector configured for emitting primary electrons in response to an incident photon; a detector configured for collecting electrons and providing an output signal representative of the incident photon; and a series of electrodes between the electron ejector and the detector, wherein each of the electrodes is configured for emitting secondary electrons in response to incident electrons, and each of the electrodes includes a bi-metal arc-shaped sheet.

Components of scientific analytical equipment. More particularly, ion detectors of the type which incorporate electron multipliers and modifications thereto for extending the operational lifetime or otherwise improving performance. The ion detector may be embodied in the form of a particle detector having one or more electron emissive surfaces and/or an electron collector surface therein, the particle detector being configured such that in operation the environment about the electron emissive surface(s) and/or the electron collector surface is/are different to the environment immediately external to the detector.

Components of scientific analytical equipment. More particularly, ion detectors of the type which incorporate electron multipliers and modifications thereto for extending the operational lifetime or otherwise improving performance. The ion detector may be embodied in the form of a particle detector having one or more electron emissive surfaces and/or an electron collector surface therein, the particle detector being configured such that in operation the environment about the electron emissive surface(s) and/or the electron collector surface is/are different to the environment immediately external to the detector.

Disclosed herein is a photomultiplier comprising: an electron ejector; a detector; a substrate; and a first electrode in the substrate; a second electrode in the substrate; a third electrode in the substrate; wherein each of the first, second and third electrodes comprises a flat or curved surface at an angle to a normal direction of the substrate; wherein each of the first, second and third electrodes comprises a first end and a second end, the first end being closer to the electron ejector than the second end; wherein the first, second and third electrodes are spatially arranged such that the second ends of the first, second and third electrode are on a same plane, or such that a plane the second ends of the first and third electrodes are on crosses the second electrode.

Disclosed herein is a photomultiplier comprising: an electron ejector; a detector; a substrate; and a first electrode in the substrate; a second electrode in the substrate; a third electrode in the substrate; wherein each of the first, second and third electrodes comprises a flat or curved surface at an angle to a normal direction of the substrate; wherein each of the first, second and third electrodes comprises a first end and a second end, the first end being closer to the electron ejector than the second end; wherein the first, second and third electrodes are spatially arranged such that the second ends of the first, second and third electrode are on a same plane, or such that a plane the second ends of the first and third electrodes are on crosses the second electrode.

The invention relates to mass spectrometers having secondary electron multipliers with series of discrete dynode stages. The invention particularly relates to an operation with extended dynamic measuring range and extended lifetime. The invention is based on not adapting the dynamic measuring range by control of the gain of the trans-impedance amplifier, nor controlling the multiplier operating voltage, which both are usually too slow, but alternating a number of active and passive dynode stages of a discrete dynode multiplier. Each dynode stage is connected to a discrete voltage supply circuit, being able to be de-energized and short-cut; the multiplier gain is feedback-controlled by energizing or short-cutting dynode stages, serially from the end of the multiplier, as a function of a last measured ion signal; and the multiplier has a single trans-impedance amplifier and a single analog-to-digital converter, measuring and digitizing the output current of the last active dynode stage.

The invention relates to mass spectrometers having secondary electron multipliers with series of discrete dynode stages. The invention particularly relates to an operation with extended dynamic measuring range and extended lifetime. The invention is based on not adapting the dynamic measuring range by control of the gain of the trans-impedance amplifier, nor controlling the multiplier operating voltage, which both are usually too slow, but alternating a number of active and passive dynode stages of a discrete dynode multiplier. Each dynode stage is connected to a discrete voltage supply circuit, being able to be de-energized and short-cut; the multiplier gain is feedback-controlled by energizing or short-cutting dynode stages, serially from the end of the multiplier, as a function of a last measured ion signal; and the multiplier has a single trans-impedance amplifier and a single analog-to-digital converter, measuring and digitizing the output current of the last active dynode stage.

The invention relates to mass spectrometers having secondary electron multipliers with series of discrete dynode stages. The invention particularly relates to an operation with extended dynamic measuring range and extended lifetime. The invention is based on not adapting the dynamic measuring range by control of the gain of the trans-impedance amplifier, nor controlling the multiplier operating voltage, which both are usually too slow, but alternating a number of active and passive dynode stages of a discrete dynode multiplier. Each dynode stage is connected to a discrete voltage supply circuit, being able to be de-energized and short-cut; the multiplier gain is feedback-controlled by energizing or short-cutting dynode stages, serially from the end of the multiplier, as a function of a last measured ion signal; and the multiplier has a single trans-impedance amplifier and a single analog-to-digital converter, measuring and digitizing the output current of the last active dynode stage.

The invention relates to mass spectrometers having secondary electron multipliers with series of discrete dynode stages. The invention particularly relates to an operation with extended dynamic measuring range and extended lifetime. The invention is based on not adapting the dynamic measuring range by control of the gain of the trans-impedance amplifier, nor controlling the multiplier operating voltage, which both are usually too slow, but alternating a number of active and passive dynode stages of a discrete dynode multiplier. Each dynode stage is connected to a discrete voltage supply circuit, being able to be de-energized and short-cut; the multiplier gain is feedback-controlled by energizing or short-cutting dynode stages, serially from the end of the multiplier, as a function of a last measured ion signal; and the multiplier has a single trans-impedance amplifier and a single analog-to-digital converter, measuring and digitizing the output current of the last active dynode stage.

Disclosed herein is a photomultiplier comprising: an electron ejector; a detector; a substrate; and a first electrode in the substrate; a second electrode in the substrate; a third electrode in the substrate; wherein each of the first, second and third electrodes comprises a flat or curved surface at an angle to a normal direction of the substrate; wherein each of the first, second and third electrodes comprises a first end and a second end, the first end being closer to the electron ejector than the second end; wherein the first, second and third electrodes are spatially arranged such that the second ends of the first, second and third electrode are on a same plane, or such that a plane the second ends of the first and third electrodes are on crosses the second electrode.