Mass spectrometer

Abstract

A mass spectrometer 100 comprises a pump 50 having a pump longitudinal axis. The pump 50 comprises a plurality of vacuum stages arranged along the pump longitudinal axis. First, second, and third pump

Description

Background The present specification relates to a mass spectrometer, and method of analysing a sample. In particular this may be a mass spectrometer for inductively coupled plasma mass spectrometry (ICP-MS), but equally could be applied to any type of mass spectrometer. In inductively coupled plasma mass spectrometry a sample to be tested is ionized using inductively coupled plasma. This creates ions from which the respective masses are then detected in order to identify the ions of the sample. In ICP-MS, ions are produced in a plasma chamber, and may then pass through a vacuum interface and a first mass filter (typically a multipole, such as a quadrupole, hexapole, or octupole) into a collision cell. After the collision cell they then pass through another mass filter (typically a further multipole, such as a quadrupole, hexapole, or octupole) and on to a detector for identifying the ions. Each of the multipoles and the collision cell have a vacuum applied thereto by one or more vacuum pumps. Typically, these components are arranged in a straight line. This results in a large device, and complex connections between the vacuum pump resulting in a low efficiency, or the need to use multiple vacuum pumps. US 7 211 788 B2 shows a mass spectrometer where the various components are arranged in a linear manner. Separate vacuum pumps are provided for each component. This increases the complexity of the system and overall size. US 8 481 923 B1 shows a mass spectrometer where the various components are still arranged in a linear manner, but the multiple vacuum pumps are replaced by a single vacuum pump having multiple stages which deliver different pressures (and hence different strengths of vacuum). As the successive required vacuum strengths are not necessarily increasing linearly, this results in the complex tubing as shown in Figure 2 of US 8 481 923 B1. Each turn in the vacuum plumbing can reduce the efficiency of the system. US 6 525 314 B1 shows a system where the collision cell and quadrupoles are not arranged in a linear manner. However the overall size of the device is still larger than is necessary and additional tubing is still required to deliver the vacuum as shown in Figure 3 of US 6 525 314 B1. There is therefore the need for an improved mass spectrometer. Summary A mass spectrometer is provided. The mass spectrometer comprises: a pump having a pump longitudinal axis, the pump comprising a plurality of vacuum stages arranged along the pump longitudinal axis; an inlet for receiving a sample; a first pumped component having a first longitudinal axis, the first pumped component arranged to receive the sample from the inlet, the first pumped component fluidly connected to a first vacuum stage of the plurality of vacuum stages; a second pumped component having a second longitudinal axis, the second pumped component arranged to receive the sample from the first pumped component, the second pumped component fluidly connected to a second vacuum stage; and a third pumped component having a third longitudinal axis, the third pumped component arranged to receive the sample from the second pumped component, the third pumped component fluidly connected to a vacuum stage of the plurality of vacuum stages at a lower pressure than the vacuum stage fluidly connected to the second pumped component, wherein: the first longitudinal axis and the second longitudinal axis are transverse at a first angle to one another, the second longitudinal axis and the third longitudinal axis are transverse at a second angle to one another; the third longitudinal axis and the pump longitudinal axis defining a third angle, the third angle is between 0° and 30°. This mass spectrometer allows for an overall reduction in size by arranging the various components with respect to the pump. This mass spectrometer is more compact than existing systems and takes advantage of being arranged around the pump to connect to the various stages. The third angle being between 0° and 30° is agnostic on the direction of the angle. In other words, this includes ±30°. It is the magnitude of the third angle. This is the case for all definitions of the third angle. A vacuum stage is a section of the pump which generates a vacuum at a particular pressure level. There may be one or more sets of rotors between vacuum stages which act to generate the different vacuum pressures. While the vacuum stage is identified as a “first” vacuum stage here it is noted that there could be one or more vacuum stages in the pump before this “first” vacuum stage. In this context, transverse means at an angle to one another - i.e., not parallel or coincident. Throughout the specification, various longitudinal axes are defined. In general, each refers to a conceptual axis which passes along the primary dimension of a component. This may be, for example, a direction which a sample being tested by the mass spectrometer flows through the particular component. For example, this may also correspond to a dimension of the component in which it is elongated. Each vacuum stage may decrease in pressure along the pump longitudinal axis. The first longitudinal axis and the second longitudinal axis may be in a first plane. The second longitudinal axis and the third longitudinal axis may be in a second plane. The first angle and the second angle may each (or individually) be between 45° and 135°. The second vacuum stage may be configured to be at a higher pressure than the first vacuum stage and the third vacuum stage may be configured to be at a lower pressure than the second vacuum stage. In other words, the stages are not linear in order of vacuum strength. The arrangement of the pumped components allows for this while avoiding the need for complex tubing and connections. The third vacuum stage may be configured to be at a lower pressure than the first vacuum stage. Again, the arrangement of the pumped components allows for this while avoiding the need for complex plumbing. The first angle and / or the second angle may be between 45° and 135°, preferably between 70° and 110°, more preferably between 80° and 100°, most preferably between 85° and 95°. These are suitable angles for arranging the various pumped components in order to minimise the size of the mass spectrometer. The first longitudinal axis and the second longitudinal axis may be substantially perpendicular; and / or the second longitudinal axis and the third longitudinal axis may be substantially perpendicular. Substantially perpendicular includes perpendicular, as well as deviations therefrom. Perpendicular is a particularly suitable angle for arranging the various pumped components in order to minimise the size of the mass spectrometer. The third angle may be between 0° and 20°, more preferably between 0° and 10°, most preferably between 0° and 5°. Again, this is the magnitude of the third angle and encompasses ± each value. These are suitable angles for arranging the various pumped components in order to minimise the size of the mass spectrometer. The third longitudinal axis and the pump longitudinal axis may be substantially parallel. Substantially parallel includes parallel, as well as deviations therefrom. Parallel is a particularly suitable angle for arranging the various pumped components in order to minimise the size of the mass spectrometer. The first longitudinal axis, the second longitudinal axis, and the third longitudinal axis may be substantially mutually orthogonal. Substantially mutually orthogonal includes mutually orthogonal, as well as deviations therefrom. Having the three axes mutually orthogonal allows for further minimisation of the size of the mass spectrometer, while delivering vacuum to each pumped component. The pump may be arranged with each of the first pumped component, second pumped component, and third pumped component adjacent to the pump. Having every component adjacent to the pump helps avoid complex plumbing to connect the pump to each pumped component. The mass spectrometer may further comprise a detector with a detector longitudinal axis, the detector being arranged offset relative to the pump in a direction of the pump longitudinal axis. This offset may be that the detector is below, or underneath, the pump in use. The offset may be such that in plan view the detector and pump at least partially overlap. The detector allows for identification of the ions, and may help reduce the overall footprint of the apparatus by placing the detector in otherwise unused space under the pump. The detector longitudinal axis can be defined as being the direction of sample flow into the detector. The third longitudinal axis and the detector longitudinal axis may be transverse at a fourth angle to one another. This can put the detector at an angle which means it is easy to access. The fourth angle is between 45° and 135°, preferably between 70° and 110°, more preferably between 80° and 100°, most preferably between 85° and 95°. This can put the detector at an angle which means it is easy to access. In further examples, the third longitudinal axis and the detector longitudinal axis may be substantially parallel. Substantially parallel includes parallel, as well as deviations therefrom. For example, ±30°, ±20°, ±10° and / or ±5°. The third longitudinal axis and the detector longitudinal axis may be substantially perpendicular. Substantially perpendicular includes perpendicular, as well as deviations therefrom. This is a particular angle which means the detector is easy to access. In a direction of the pump longitudinal axis, the first pumped component may be aligned with the first vacuum stage; and / or the second pumped component may be aligned with the second vacuum stage; and / or the third pumped component may be aligned with the third vacuum stage. That is, the first pumped component and the first vacuum stage (or any of the other respective pairs of component and vacuum stage) may be at a same point along the pump longitudinal axis. In other words, they are both intersected by a plane perpendicular / orthogonal to the pump longitudinal axis. One or more of these alignments also includes any combination of these components being aligned. In this context, aligned means that there is at least some overlap in the direction of the pump longitudinal axis. For example, this alignment and / or overlap may be when they are viewed at an angle perpendicular to the pump longitudinal axis. This allows for easy delivery of the vacuum to each pumped component, taking advantage of the presently claimed arrangement of the pumped components. The first pumped component may be a first multipole. As explained below, in certain examples the mass spectrometer may not include any first multipole or first pumped component. Specifically, the multipole could be a quadrupole, hexapole, or octupole, or any other multipole. In certain cases, the first multipole may be used as a mass filter in the system. The second pumped component may comprise a collision cell. The collision cell has entry and exit openings, through which gas can leak out. This leaked gas can then be removed by the vacuum. A feed tube can supply collision gas to an interior of the collision cell. The third pumped component may be a second multipole. Specifically, the multipole could be a quadrupole, hexapole, or octupole, or any other multipole. The pump may be a cartridge type turbo pump. In general, the pump may be referred to as a vacuum pump. The mass spectrometer may further comprise a plasma chamber arranged to deliver the sample to the inlet, the plasma chamber being configured for ionizing the sample, typically by using a plasma torch and a fluid injector. The plasma chamber can have a plasma chamber longitudinal axis. The flow direction of the fluid / sample through the injector into the plasma torch may define the plasma chamber longitudinal axis. That is, the plasma chamber longitudinal axis may be in the direction of sample flow through the plasma chamber. The plasma chamber longitudinal axis and the first longitudinal axis may be transverse at a fifth angle to one another. This further allows for the components to be arranged to reduce the overall size of the mass spectrometer. Again, the plasma chamber longitudinal axis may be defined based on a direction of sample flow therethrough. The fifth angle may be between 45° and 135°, preferably between 70° and 110°, more preferably between 80° and 100°, most preferably between 85° and 95°. These are suitable angles for arranging the various components in order to minimise the size of the mass spectrometer. The plasma chamber longitudinal axis and the first longitudinal axis may be substantially perpendicular. Substantially perpendicular includes perpendicular, as well as deviations therefrom. Perpendicular is a particularly suitable angle for arranging the various pumped components in order to minimise the size of the mass spectrometer. The mass spectrometer may further comprise a spray chamber arranged to deliver the sample to the plasma chamber, the spray chamber having a spray chamber longitudinal axis. The spray chamber longitudinal axis and the plasma chamber longitudinal axis may define a sixth angle, the sixth angle being between 0° and 30°. Again, this is the magnitude of the sixth angle and encompasses ± each value. This further allows for the components to be arranged to reduce the overall size of the mass spectrometer. The sixth angle may be between 0° and 20°, more preferably between 0° and 10°, most preferably between 0° and 5°. Again, this is the magnitude of the sixth angle and encompasses ± each value. These are suitable angles for arranging the various pumped components in order to minimise the size of the mass spectrometer. The spray chamber longitudinal axis and the plasma chamber longitudinal axis may be substantially parallel. Substantially parallel includes parallel, as well as deviations therefrom. Parallel is a particularly suitable angle for arranging the various pumped components in order to minimise the size of the mass spectrometer. A method of analysing a sample is provided. In this method, the sample is delivered to the inlet of a mass spectrometer as discussed herein. Brief Description of the Drawings The present specification makes reference, by way of example only, to the accompanying drawings in which: Figure 1 shows a perspective view of a first mass spectrometer; Figure 2 shows a top view of the first mass spectrometer of Figure 1; Figure 3 shows a perspective view of a second mass spectrometer; and Figure 4 shows a top view of the second mass spectrometer of Figure 3. Detailed Description Figure 1 shows a schematic perspective view of a first mass spectrometer 100, with Figure 2 the corresponding top view. This may be a mass spectrometer 100 for inductively coupled plasma mass spectrometry (ICP-MS), but equally could be any type of mass spectrometer 100. It is noted that the Figures are schematic in nature, and for clarity certain ion optics components have been omitted. In general, there may be a connector between adjacent components for the ion flow. The mass spectrometer 100 comprises a pump 50. This pump 50 can also be generally referred to as a vacuum pump. The pump 50 has a pump longitudinal axis. That is, an axis extending along the longest dimension of the pump 50. Typically, the pump longitudinal axis coincides with the axle of the pump rotor. The pump 50 comprises a plurality of vacuum stages, each for supplying a vacuum. One or more of the vacuum stages may be at a different pressure. A lower pressure for a vacuum stage results in a stronger vacuum, and vice-versa. However, it is also possible for one or more of the vacuum stages to be at the same pressure as one another. For example, the pump 50 may generate a vacuum by virtue of one or more sets of vanes which rotate about a central shaft. There may be a set of vanes between two vacuum stages in order to generate a lower pressure in one stage than another. It may be that there are no vanes between two vacuum stages. This would mean that these two stages would be at substantially the same pressure. In general, the further along the pump longitudinal axis from the motor the lower the pressure and hence the stronger the vacuum. In other words, the vacuum stages may decrease in pressure along the pump longitudinal axis. Figure 1 shows the pump 50 as a cartridge type turbo pump,, but any suitable vacuum pump may be used, provided that it is suitable for generating a vacuum in various vacuum stages. In a cartridge type turbo pump there is no separate external housing of the pump. Each of the vacuum stages are exposed for connection to additional components. The mass spectrometer 100 further comprises an inlet for receiving a sample to be analysed using the mass spectrometer 100. The inlet feeds into a first pumped component 10. The first pumped component 10 is arranged to receive the sample from the inlet to the mass spectrometer 100. This may be a direct connection or there may be one or more intermediate components. Throughout the specification, ordinal adjectives (i.e. “first”, “second”, “third”, etc.) are used to refer to various pumped components. The use of these ordinal adjectives is for identification only, and does not imply that these are necessarily all present. For example, it may be possible to have the second pumped component 15 (discussed below) without the first pumped component 10. Likewise, there may be additional components in the mass spectrometer 100 which are provided with vacuum. These additional components may be before or after any of the pumped components 10, 15, 20 discussed herein in the flow through the mass spectrometer 100. For the avoidance of doubt, the ordinal adjective for any pumped component (or indeed any other component which is also supplied with vacuum) can be renumbered for enhanced clarity. While Figures 3 and 4 will be discussed in detail below it is noted that the primary difference is that the first pumped component 10 shown in Figure 1 is omitted. The first pumped component 10 has a first longitudinal axis. This first longitudinal axis extends centrally along the first pumped component 10 in its greatest dimension and / or in a direction of flow of the sample through the first pumped component 10. In certain examples, the first pumped component 10 may comprise a first multipole, for example a first quadrupole Q1 (or hexapole, or octupole) of the mass spectrometer 100. This first multipole can operate in the mass spectrometer 100 as a first mass filter. That is, the first pumped component 10 may be a mass filter. Such a first mass filter can, however, be omitted from a mass spectrometer 100 such as shown in Figures 3 and 4. A first vacuum stage of the pump 50 is fluidly connected to the first pumped component 10, for applying a vacuum to the first pumped component 10. This may be a direct connection between the first pumped component 10 and the first vacuum stage. Particularly, a connection without any significant turns or bends - a straight connection - is preferred. In addition, the distance between a pump opening and a place where gas leaves the pumped components is preferably minimized. Also, the pump is preferred to have a large cross-sectional area. The opening of the pump could, for example, be up to 25% (i.e. 90°) of the outer circumference of the pump 50, or indeed even more. In certain cases, the opening could be at least 10% or at least 15% of the outer circumference of the pump 50. The opening being the portion of the pump 50 which is connected to the pumped components 10, 15, 20. Throughoutthe specification, ordinal adjectives (i.e. “first”, “second”, “third”, etc.) are used to refer to various vacuum stages of the pump 50. The use of these ordinal adjectives is for identification only, and does not imply that these are necessarily all present. For example, it may be possible to have the second vacuum stage (discussed below) without the first vacuum. Likewise, there may be additional vacuum stage in the pump 50. These additional vacuum stages may be before or after any of the vacuum stages discussed herein. For example, there may be at least one vacuum stage preceding the vacuum stage identified as the “first” vacuum stage herein. For the avoidance of doubt, the ordinal adjective for any vacuum stage can be renumbered for enhanced clarity. The first longitudinal axis and the pump longitudinal axis may be transverse to one another. In other words, at an angle to one another. In certain examples they may be perpendicular (i.e. 90°) or substantially perpendicular. The angle may also be any angle between and including 45° and 135°. For example between 70° and 110°, or between 80° and 100°, or between 85° and 95°. Substantially perpendicular may be defined based on any of these ranges. The mass spectrometer 100 further comprises a second pumped component 15. The second pumped component 15 receives the sample from the first pumped component 10. This may be, for example, via a first connector 12. This could be via a first curvature part 12, which causes the ion beam / trajectory to curve between the first pumped component 10 and the second pumped component 15. For example, this could be over an angle of, in the example shown, approximately 90 degrees. The sample ions entering the second pumped component 15 have undergone any processing, such as filtering, performed in the first pumped component 10. In examples without a first pumped component 10 the inlet may deliver the sample directly to the second pumped component 15. Although not shown in the Figures, ion optical components, such as lenses, can be provided between the first pumped component 10 and the second pumped component 15 in order to redirect the sample from the first pumped component 10 to the second pumped component 15. Throughout the specification, ordinal adjectives (i.e. “first”, “second”, “third”, etc.) are used to refer to various connectors. The use of these ordinal adjectives is for identification only, and does not imply that these are necessarily all present. For example, it may be possible to have the second connector 18 (discussed below) without the first connector 12. Likewise, there may be additional connectors in the mass spectrometer 100. These additional connectors may be before or after any of the pumped components 10, 15, 20 discussed herein in the flow through the mass spectrometer 100. For the avoidance of doubt, the ordinal adjective for any connector can be renumbered for enhanced clarity. The second (indirectly) pumped component 15 has a second longitudinal axis. This second longitudinal axis extends centrally along the second pumped component 15 in its greatest dimension and / or in a direction of flow of the sample through the second pumped component 15. In certain examples, the second pumped component 15 may comprise a collision cell of the mass spectrometer 100. The collision cell may comprise an inlet for receiving the sample, and an outlet for letting out the sample, and a gas feed for receiving a collision gas. The gas feed may be, for example, by a gas feed tube. A second vacuum stage of the pump 50 is fluidly connected to the second pumped component 15, for applying a vacuum to the second pumped component 15. This may be a direct connection between the second pumped component 15 and the second vacuum stage. Particularly, a connection without any significant turns or bends - a straight connection - is preferred. The second vacuum stage may be at a higher pressure (and hence a weaker vacuum) than the first vacuum stage. In other words, where the vacuum stages decrease in pressure along the pump longitudinal axis, the second vacuum stage may be before the first vacuum stage. This second vacuum stage can act to draw any material which leaks from the inlet or outlet of the collision cell, as opposed to being directly applied to the collision cell. For example, the collision cell may be within a larger container, this external larger container being the second pumped component 15 which is directly connected to the second vacuum stage. The first longitudinal axis of the first pumped component 10 and the second longitudinal axis of the second pumped component 15 may be in a first plane with one another. The first longitudinal axis of the first pumped component 10 and the second longitudinal axis of the second pumped component 15 may be transverse to one another. In other words, at a first angle to one another. The first connector 12 (such as first curvature part 12) can be shaped to curve the ion beam / trajectory over the first angle. In certain examples this first angle is perpendicular (i.e. 90°) or substantially perpendicular. The first angle may also be any angle between and including 45° and 135°. For example between 70° and 110°, or between 80° and 100°, or between 85° and 95°. Substantially perpendicular may be defined based on any of these ranges. The pump 50 is between the first pumped component 10 and the second pumped component 15. For example, if the first angle were bisected then the bisected angle would pass through the pump. The second longitudinal axis and the pump longitudinal axis may be transverse to one another. In other words, at an angle to one another. In certain examples they may be perpendicular (i.e. 90°) or substantially perpendicular. The angle may also be any angle between and including 45° and 135°. For example between 70° and 110°, or between 80° and 100°, or between 85° and 95°. Substantially perpendicular may be defined based on any of these ranges. The mass spectrometer 100 further comprises a third pumped component 20. The third pumped component 20 receives the sample from the second pumped component 15. This may be, for example, via a second connector 18. This could be via a second curvature part 18 which causes the ion beam / trajectory to curve between the second pumped component 15 and the third pumped component 20. For example, this could be over an angle of, in the example shown, approximately 90 degrees. The sample ions entering the third pumped component 20 have undergone any processing, such as filtering, performed in the second pumped component 15. Although not shown in the Figures, ion optical components, such as lenses, can be provided between the second pumped component 15 and the third pumped component 20 in order to redirect the sample from the second pumped component 15 to the third pumped component 20. The third pumped component 20 has a third longitudinal axis. This third longitudinal axis extends centrally along the third pumped component 20 in its greatest dimension and / or in a direction of flow of the sample through the third pumped component 20. In certain examples, the third pumped component 20 may be a second multipole, for example a second quadrupole Q2 (or hexapole, or octupole) of the mass spectrometer 100. The second multipole may have the same number of poles as first multipole, or a different number. As noted above, the first pumped component 10 may be omitted. In such cases where, the third pumped component 20 may be a first multipole, such as a first quadrupole (or hexapole, or octupole). A third vacuum stage of the pump 50 is fluidly connected to the third pumped component 20, for applying a vacuum to the third pumped component 20. This may be a direct connection between the third pumped component 20 and the third vacuum stage. Particularly, a connection without any significant turns or bends - a straight connection. The third vacuum stage may be at a lower pressure (and hence a stronger vacuum) than the second vacuum stage. In other words, where the vacuum stages decrease in pressure along the pump longitudinal axis, the third vacuum stage may be after the second vacuum stage. The first vacuum stage and the third vacuum stage may be at the same pressure as one another. For example, they may be co-incident in the pump 50. In further examples, the third vacuum stage may be at a lower pressure (and hence a stronger vacuum) than the first vacuum stage. In other words, where the vacuum stages decrease in pressure along the pump longitudinal axis, the third vacuum stage may be after the first vacuum stage. For example, the order may be the second vacuum stage then the first vacuum stage then the third vacuum stage. This is in order of decreasing pressure and hence increasing vacuum strength. The third longitudinal axis of the third pumped component 20 and the pump longitudinal axis may define a third angle. This third angle may be between 0° and 30°. The third angle being between 0° and 30° is agnostic on the direction of the third angle. In other words this includes ±30°. It is the magnitude of the third angle. The third longitudinal axis of the third pumped component 20 and the pump longitudinal axis may be parallel (i.e. 0°) or substantially parallel. The third angle may also be any angle between and including 0° and 30°. For example between 0° and 20°, or between 0° and 10°, or between 0° and 5°. Substantially parallel may be defined based on any of these ranges. That is, the third pumped component 20 and the pump 50 may extend in generally the same direction as one another. They may each be elongate in this direction. This is useful as the third vacuum stage may also be further along the pump longitudinal axis in this direction and hence the greater vacuum level can be delivered to the third pumped component 20. The third longitudinal axis and the first longitudinal axis may be transverse to one another. In other words, at an angle to one another. In certain examples they may be perpendicular (i.e. 90°) or substantially perpendicular. The angle may also be any angle between and including 45° and 135°. For example between 70° and 110°, or between 80° and 100°, or between 85° and 95°. Substantially perpendicular may be defined based on any of these ranges. The second longitudinal axis of the second pumped component 15 and the third longitudinal axis of the third pumped component 20 may be in a second plane with one another. The third longitudinal axis and the second longitudinal axis may be transverse to one another. In other words, at a second angle to one another. The second connector 18 (such as second curvature part 18) can be shaped to curve the ion beam / trajectory over the first angle. In certain examples they may be perpendicular (i.e. 90°) or substantially perpendicular. The angle may also be any angle between and including 45° and 135°. For example between 70° and 110°, or between 80° and 100°, or between 85° and 95°. Substantially perpendicular may be defined based on any of these ranges. In certain examples, the first longitudinal axis, the second longitudinal axis, and the third longitudinal axis may be mutually orthogonal to one another, or substantially mutually orthogonal to one another. By mutually orthogonal it means that each axis is perpendicular to the other two. This arrangement of the first pumped component 10, second pumped component 15 and third pumped component 20 allows them to be set rotationally and longitudinally around the pump 50. This can be seen in Figures 1 and 2 and allows for the overall size of the mass spectrometer 100 to be reduced compared to a similar mass spectrometer with its components arranged in a straight line as in the prior art. In general, and across each of the examples discussed herein, from a plan view of the pump 50, in the direction of the pump longitudinal axis, a pump outer perimeter may be defined. The respective pumped components 10, 15, 20 which are present in the particular example are arranged outwardly (from a centre of the pump 50) of the pump outer perimeter over a significant portion thereof. For example, this may be at least 25% of the pump outer perimeter. Specifically, with a substantially cylindrical pump 50, there may be pumped components 10, 15, 20 arranged spanning at least 90° from the longitudinal axis of the pump 50. Preferably, this may be at least 110°. As a result, each vacuum stage can be connected to the respective pumped component 10, 15, 20 without the need for complex tubing. A direct connection can be made between the respective vacuum stage and pumped component 10,15, 20. As a part of this, the first pumped component 10 may be aligned with the first vacuum stage; and / or the second pumped component 15 may be aligned with the second vacuum stage; and / or the third pumped component 20 may be aligned with the third vacuum stage. This could be seen, for example, in a view perpendicular to the pump longitudinal axis. Because of this alignment a straight connector can be used to convey each vacuum, even though they are at different pressures and hence different positions along this longitudinal axis. The alignment only needs to be some degree of overlap in this view, such that the vacuum can be appropriately transferred. Each pumped component 10, 15, 20 may be adjacent to the pump 50. That is, they are all directly next to the pump 50 without any intermediate component or wall. For example, they may all be spaced from the pump at substantially the same distance when viewed in plan view. For example, within 10% of the same distance in plan view. The mass spectrometer may further comprise a detector 60. The detector 60 carries out the identification of the ions in the sample. The detector 60 receives the sample from the third pumped component 20. The detector 60 has a detector longitudinal axis. This detector longitudinal axis extends centrally along the detector 60 in its greatest dimension and / or in a direction of flow of the sample into / through the detector 60. The detector longitudinal axis and the third longitudinal axis of the third pumped component 20 may be in a third plane with one another. The detector longitudinal axis and the third longitudinal axis of the third pumped component 20 may be transverse to one another. In other words, at a fourth angle to one another. In certain examples this fourth angle is perpendicular (i.e. 90°) or substantially perpendicular. The fourth angle may also be any angle between and including 45° and 135°. For example between 70° and 110°, or between 80° and 100°, or between 85° and 95°. Substantially perpendicular may be defined based on any of these ranges. The detector longitudinal axis and the second longitudinal axis of the second pumped component 15 may be transverse to one another. In other words, at an angle to one another. In certain examples this angle is perpendicular (i.e. 90°) or substantially perpendicular. The angle may also be any angle between and including 45° and 135°. For example between 70° and 110°, or between 80° and 100°, or between 85° and 95°. Substantially perpendicular may be defined based on any of these ranges. The detector longitudinal axis and the pump longitudinal axis may be transverse to one another. In other words, at an angle to one another. In certain examples this angle is perpendicular (i.e. 90°) or substantially perpendicular. The angle may also be any angle between and including 45° and 135°. For example between 70° and 110°, or between 80° and 100°, or between 85° and 95°. Substantially perpendicular may be defined based on any of these ranges. The detector may or may not be pumped and may thus be fluidly connected to a suitable vacuum stage. The detector longitudinal axis and the first longitudinal axis of the first pumped component 10 may define an angle. This angle may be between 0° and 30°. The angle being between 0° and 30° is agnostic on the direction of the angle. In other words, this includes ±30°. It is the magnitude of the angle. The detector longitudinal axis and the first longitudinal axis of the first pumped component 10 may be parallel (i.e. 0°) or substantially parallel. The angle may also be any angle between and including 0° and 30°. For example between 0° and 20°, or between 0° and 10°, or between 0° and 5°. Substantially parallel may be defined based on any of these ranges. That is, the detector 60 and the first pumped component 10 may extend in generally the same direction as one another. They may each be elongate in this direction. The detector 60 is arranged offset from the pump 50 in the longitudinal direction, for example underneath or above the pump 50. That is, in plan view the detector 60 and pump 50 at least partially overlap. In use, the detector 60 may be readily detachable such that it can be removed from the mass spectrometer 100, such as for servicing, repair and / or cleaning. The longitudinal axis of the detector 60 may be substantially parallel with, or coincide with, the longitudinal axis of the third pumped component 20. The mass spectrometer 100 may further comprise one or more additional components upstream of the first component 10. In Figure 1, there is a spray chamber 2 and a plasma chamber 3, with a plasma connector 4 between the plasma chamber 3 and the first pumped component 10. One or more of the spray chamber 2, plasma chamber 3, and / or plasma connector 4 may be omitted. The spray chamber 2 feeds the sample into the plasma chamber 3. The plasma chamber 3 then feeds into the plasma connector 4 and hence the first pumped component 10. There may be a connecting portion between the spray chamber 2 and the plasma chamber 3, or they may be immediately adjacent to one another such as shown in Figure 1. The plasma chamber 2 is configured to ionizing the sample. Typically, this could be by using a plasma torch and a fluid injector. The spray chamber 2 has a spray chamber longitudinal axis. This spray chamber longitudinal axis extends centrally along the spray chamber 2 in its greatest dimension and / or in a direction of flow of the sample through the spray chamber 2. The flow direction of the fluid / sample through the spray chamber 2 may define the spray chamber longitudinal axis. That is, the spray chamber longitudinal axis may be in the direction of fluid flow through the spray chamber 2. The spray chamber 2 may be at atmospheric pressure. The plasma chamber 3 has a plasma chamber longitudinal axis. This plasma chamber longitudinal axis extends centrally along the plasma chamber 3 in its greatest dimension and / or in a direction of flow of the sample through the plasma chamber 3. The flow direction of the fluid / sample through the plasma chamber 3, such as through the injector into the plasma torch, may define the plasma chamber longitudinal axis. That is, the plasma chamber longitudinal axis may be in the direction of sample flow through the plasma chamber 3. The plasma chamber 3 may be at atmospheric pressure. The spray chamber longitudinal axis and the plasma chamber longitudinal axis may define a sixth angle. This sixth angle may be between 0° and 30°. The sixth angle being between 0° and 30° is agnostic on the direction of the sixth angle. In other words, this includes ±30°. It is the magnitude of the sixth angle. The spray chamber longitudinal axis and the plasma chamber longitudinal axis may be parallel (i.e. 0°) or substantially parallel. The sixth angle may also be any angle between and including 0° and 30°. For example between 0° and 20°, or between 0° and 10°, or between 0° and 5°. Substantially parallel may be defined based on any of these ranges. That is, the spray chamber 2 and the plasma chamber 3 may extend in generally the same direction as one another. They may each be elongate in this direction. The plasma chamber longitudinal axis and the first longitudinal axis of the first pumped component 10 may be in a plane with one another. The plasma chamber longitudinal axis and the first longitudinal axis of the first pumped component 10 may be transverse to one another. In other words, at a fifth angle to one another. In certain examples this fifth angle is perpendicular (i.e. 90°) or substantially perpendicular. The fifth angle may also be any angle between and including 45° and 135°. For example between 70° and 110°, or between 80° and 100°, or between 85° and 95°. Substantially perpendicular may be defined based on any of these ranges. The plasma chamber longitudinal axis and the second longitudinal axis of the second pumped component 15 may be transverse to one another. In other words, at an angle to one another. In certain examples this angle is perpendicular (i.e. 90°) or substantially perpendicular. The angle may also be any angle between and including 45° and 135°. For example between 70° and 110°, or between 80° and 100°, or between 85° and 95°. Substantially perpendicular may be defined based on any of these ranges. The plasma chamber longitudinal axis and the detector longitudinal axis may be transverse to one another. In other words, at an angle to one another. In certain examples this angle is perpendicular (i.e. 90°) or substantially perpendicular. The angle may also be any angle between and including 45° and 135°. For example between 70° and 110°, or between 80° and 100°, or between 85° and 95°. Substantially perpendicular may be defined based on any of these ranges. The plasma chamber longitudinal axis and the third longitudinal axis of the third pumped component 20 may define an angle. This angle may be between 0° and 30°. The angle being between 0° and 30° is agnostic on the direction of the angle. In other words this includes ±30°. It is the magnitude of the angle. The plasma chamber longitudinal axis and the third longitudinal axis of the third pumped component 20 may be parallel (i.e. 0°) or substantially parallel. The angle may also be any angle between and including 0° and 30°. For example between 0° and 20°, or between 0° and 10°, or between 0° and 5°. Substantially parallel may be defined based on any of these ranges. That is, the plasma chamber 3 and the third pumped component 20 may extend in generally the same direction as one another. They may each be elongate in this direction. The plasma chamber longitudinal axis and the pump longitudinal axis may define an angle. This angle may be between 0° and 30°. The angle being between 0° and 30° is agnostic on the direction of the angle. In other words this includes ±30°. It is the magnitude of the angle. The plasma chamber longitudinal axis and the pump longitudinal axis may be parallel (i.e. 0°) or substantially parallel. The angle may also be any angle between and including 0° and 30°. For example between 0° and 20°, or between 0° and 10°, or between 0° and 5°. Substantially parallel may be defined based on any of these ranges. That is, the plasma chamber 3 and the pump 50 may extend in generally the same direction as one another. They may each be elongate in this direction. The spray chamber longitudinal axis and the first longitudinal axis of the first pumped component 10 may be in a plane with one another. The spray chamber longitudinal axis and the first longitudinal axis of the first pumped component 10 may be transverse to one another. In other words, at an angle to one another. In certain examples this angle is perpendicular (i.e. 90°) or substantially perpendicular. The angle may also be any angle between and including 45° and 135°. For example between 70° and 110°, or between 80° and 100°, or between 85° and 95°. Substantially perpendicular may be defined based on any of these ranges. The spray chamber longitudinal axis and the second longitudinal axis of the second pumped component 15 may be transverse to one another. In other words, at an angle to one another. In certain examples this angle is perpendicular (i.e. 90°) or substantially perpendicular. The angle may also be any angle between and including 45° and 135°. For example between 70° and 110°, or between 80° and 100°, or between 85° and 95°. Substantially perpendicular may be defined based on any of these ranges. The spray chamber longitudinal axis and the detector longitudinal axis may be transverse to one another. In other words, at an angle to one another. In certain examples this angle is perpendicular (i.e. 90°) or substantially perpendicular. The angle may also be any angle between and including 45° and 135°. For example between 70° and 110°, or between 80° and 100°, or between 85° and 95°. Substantially perpendicular may be defined based on any of these ranges. The spray chamber longitudinal axis and the third longitudinal axis of the third pumped component 20 may define an angle. This angle may be between 0° and 30°. The angle being between 0° and 30° is agnostic on the direction of the angle. In other words this includes ±30°. It is the magnitude of the angle. The spray chamber longitudinal axis and the third longitudinal axis of the third pumped component 20 may be parallel (i.e. 0°) or substantially parallel. The angle may also be any angle between and including 0° and 30°. For example between 0° and 20°, or between 0° and 10°, or between 0° and 5°. Substantially parallel may be defined based on any of these ranges. That is, the spray chamber 3 and the third pumped component 20 may extend in generally the same direction as one another. They may each be elongate in this direction. The spray chamber longitudinal axis and the pump longitudinal axis may define an angle. This angle may be between 0° and 30°. The angle being between 0° and 30° is agnostic on the direction of the angle. In other words, this includes ±30°. It is the magnitude of the angle. The spray chamber longitudinal axis and the pump longitudinal axis may be parallel (i.e. 0°) or substantially parallel. The angle may also be any angle between and including 0° and 30°. For example between 0° and 20°, or between 0° and 10°, or between 0° and 5°. Substantially parallel may be defined based on any of these ranges. That is, the spray chamber 3 and the pump 50 may extend in generally the same direction as one another. They may each be elongate in this direction. In certain examples, the spray chamber longitudinal axis and plasma chamber longitudinal axis may be co-incident with one another. The plasma connector 4 may have any suitable shape. In Figure 1 this is a right-angle (90°) connector, but equally it can be any shape depending on the angle between the plasma chamber longitudinal axis and the first longitudinal axis of the first pumped component 10. A combined longitudinal axis may be defined for the spray chamber 2 and plasma chamber 3. This may be the same as one or more of the spray chamber longitudinal axis and / or the plasma chamber longitudinal axis and can be used interchangeably therewith. Figure 3 shows a schematic perspective view of a second mass spectrometer 100, with Figure 4 the corresponding top view. Unless otherwise expressly stated otherwise this second mass spectrometer has any and all features disclosed above in relation to the first mass spectrometer 100 of Figures 1 and 2. The second mass spectrometer 100 is identical to the first mass spectrometer 100, and the disclosure above, except for in that it does not include the first pumped component 10 and the first connector 12 or first curvature part 12. Instead, flow from the plasma chamber 3 is straight into the second pumped component 10 (the collision cell) via the plasma connector 4. The relative angles of all of the other components of the second mass spectrometer 100 may be as described above. In this second mass spectrometer 100 it may be appropriate to adjust the nomenclature of each pumped component 15, 20 and vacuum stage accordingly (i.e. reduce the numbering of each by one). Otherwise, the second mass spectrometer 100 is in accordance with the disclosure regarding the first mass spectrometer 100. It will be appreciated that embodiments of the disclosure may be implemented using a variety of different information processing systems. In particular, although the Figures and the discussion thereof provide exemplary computing systems and methods, these are presented merely to provide a useful reference in discussing various aspects of the disclosure. Embodiments may be carried out on any suitable data processing device, such as a personal computer, laptop, tablet, personal digital assistant, mobile telephone, smart phone, set top box, television, server computer, etc.. Of course, the description of the systems and methods has been simplified for purposes of discussion, and they are just one of many different types of systems and methods that may be used. It will be appreciated that the boundaries between logic blocks are merely illustrative and that alternative embodiments may merge logic blocks or elements, or may impose an alternate decomposition of functionality upon various logic blocks or elements. It will be appreciated that the above-mentioned functionality may be implemented as one or more corresponding modules as hardware and / or software. For example, the above-mentioned functionality may be implemented as one or more software components for execution by a processor of the system. Alternatively, the above-mentioned functionality may be implemented as hardware, such as on one or more field-programmable-gate-arrays (FPGAs), and / or one or more application-specific-integrated-circuits (ASICs), and / or one or more digital-signal-processors (DSPs), and / or other hardware arrangements. Method steps implemented in flowcharts contained herein, or as described above, may each be implemented by corresponding respective modules. Moreover, multiple method steps implemented in flowcharts contained herein, or as described above, may be implemented together by a single module. It will be appreciated that, insofar as embodiments of the disclosure are implemented by a computer program, then a storage medium and a transmission medium carrying the computer program form aspects of the disclosure. The computer program may have one or more program instructions, or program code, that, when executed by a computer, causes an embodiment of the disclosure to be carried out. The term “program” as used herein, may be a sequence of instructions designed for execution on a computer system, and may include a subroutine, a function, a procedure, a module, an object method, an object implementation, an executable application, an applet, a servlet, source code, object code, a shared library, a dynamic linked library, and / or other sequences of instructions designed for execution on a computer system. The storage medium may be a magnetic disc (such as a hard drive or a floppy disc), an optical disc (such as a CD-ROM, a DVD-ROM or a Blu-ray disc), or a memory (such as a ROM, a RAM, EEPROM, EPROM, Flash memory or a portable / removable memory device), etc.. The transmission medium may be a communications signal, a data broadcast, a communications link between two or more computers, etc.. Each feature disclosed in this specification, unless stated otherwise, may be replaced by alternative features serving the same, equivalent, or similar purpose. Thus, unless stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features. As used herein, including in the claims, unless the context indicates otherwise, singular forms of the terms herein are to be construed as including the plural form and, where the context allows, vice versa. For instance, unless the context indicates otherwise, a singular reference herein including in the claims, such as “a” or “an” (such as a component or an element) means “one or more” (for instance, one or more components, or one or more elements). Throughout the description and claims of this disclosure, the words “comprise”, “including”, “having” and “contain” and variations of the words, for example “comprising” and “comprises” or similar, mean that the described feature includes the additional features that follow, and are not intended to (and do not) exclude the presence of other components. The use of any and all examples, or exemplary language (“for instance”, “such as”, “for example” and like language) provided herein, is intended merely to better illustrate the disclosure and does not indicate a limitation on the scope of the disclosure unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the disclosure. Any steps described in this specification may be performed in any order or simultaneously unless stated or the context requires otherwise. Moreover, where a step is described as being performed after a step, this does not preclude intervening steps being performed. All of the aspects and / or features disclosed in this specification may be combined in any combination, except combinations where at least some of such features and / or steps are mutually exclusive. In particular, the preferred features of the disclosure are applicable to all aspects and embodiments of the disclosure and may be used in any combination. Likewise, features described in non-essential combinations may be used separately (not in combination). A method of manufacturing and / or operating any of the devices disclosed herein is also provided. The method may comprise steps of providing each of the features disclosed and / or configuring or using the respective feature for its stated function.

Claims

1. A mass spectrometer comprising:a pump having a pump longitudinal axis, the pump comprising a plurality of vacuum stages arranged along the pump longitudinal axis;an inlet for receiving a sample;a first pumped component having a first longitudinal axis, the first pumped component arranged to receive the sample from the inlet, the first pumped component fluidly connected to a first vacuum stage of the plurality of vacuum stages;a second pumped component having a second longitudinal axis, the second pumped component arranged to receive the sample from the first pumped component, the second pumped component fluidly connected to a second vacuum stage; anda third pumped component having a third longitudinal axis, the third pumped component arranged to receive the sample from the second pumped component, the third pumped component fluidly connected to a vacuum stage of the plurality of vacuum stages at a lower pressure than the vacuum stage fluidly connected to the second pumped component, wherein:the first longitudinal axis and the second longitudinal axis are transverse at a first angle to one another,the second longitudinal axis and the third longitudinal axis are transverse at a second angle to one another;the third longitudinal axis and the pump longitudinal axis defining a third angle, the third angle is between 0° and 30°.

2. The mass spectrometer of claim 1, wherein the second vacuum stage is configured to be at a higher pressure than the first vacuum stage and the third vacuum stage is configured to be at a lower pressure than the second vacuum stage.

3. The mass spectrometer of claim 2, wherein the third vacuum stage is configured to be at a lower pressure than the first vacuum stage.

4. The mass spectrometer of any preceding claim, wherein the first angle and / or the second angle are between 45° and 135°, preferably between 70° and 110°, more preferably between 80° and 100°, most preferably between 85° and 95°.

5. The mass spectrometer of any preceding claim, wherein:the first longitudinal axis and the second longitudinal axis are substantially perpendicular; and / orthe second longitudinal axis and the third longitudinal axis are substantially perpendicular.

6. The mass spectrometer of any preceding claim, wherein the third angle is between 0° and 20°, more preferably between 0° and 10°, most preferably between 0° and 5°.

7. The mass spectrometer of any preceding claim, wherein the third longitudinal axis and the pump longitudinal axis are substantially parallel.

8. The mass spectrometer of any preceding claim, wherein the first longitudinal axis, the second longitudinal axis, and the third longitudinal axis are substantially mutually orthogonal.

9. The mass spectrometer of any preceding claim, wherein the pump is arranged with each of the first pumped component, second pumped component, and third pumped component adjacent to the pump.

10. The mass spectrometer of any preceding claim, further comprising a detector with a detector longitudinal axis, the detector arranged offset from the pump in a direction of the pump longitudinal axis.

11. The mass spectrometer of claim 10, wherein the third longitudinal axis and the detector longitudinal axis are transverse at a fourth angle to one another.

12. The mass spectrometer of claim 11, wherein the fourth angle is between 45° and 135°, preferably between 70° and 110°, more preferably between 80° and 100°, most preferably between 85° and 95°.

13. The mass spectrometer of claim 11 or 12, wherein:the third longitudinal axis and the detector longitudinal axis are substantially perpendicular.

14. The mass spectrometer of any preceding claim, wherein in a direction of the pump longitudinal axis:the first pumped component is aligned with the first vacuum stage; and / or the second pumped component is aligned with the second vacuum stage; and / or the third pumped component is aligned with the third vacuum stage.

15. The mass spectrometer of any preceding claim, wherein the first pumped component comprises a first multipole.

16. The mass spectrometer of any preceding claim, wherein the second pumped component comprises a collision cell.

17. The mass spectrometer of any preceding claim, wherein the third pumped component comprises a second multipole.

18. The mass spectrometer of any preceding claim, wherein the pump is a cartridge type turbo pump.

19. The mass spectrometer of any preceding claim, further comprising a plasma chamber arranged to deliver the sample to the inlet, the plasma chamber for ionizing the sample, the plasma chamber having a plasma chamber longitudinal axis.

20. The mass spectrometer of claim 19, wherein the plasma chamber longitudinal axis and the first longitudinal axis are transverse at a fifth angle to one another.

21. The mass spectrometer of claim 20, wherein the fifth angle is between 45° and 135°, preferably between 70° and 110°, more preferably between 80° and 100°, most preferably between 85° and 95°.

22. The mass spectrometer of any of claims 19 to 21, wherein:the plasma chamber longitudinal axis and the first longitudinal axis are substantially perpendicular.

23. The mass spectrometer of any of claims 19 to 22, further comprising a spray chamber arranged to deliver the sample to the plasma chamber, the spray chamber having a spray chamber longitudinal axis.5 24. The mass spectrometer of claim 23, wherein the spray chamber longitudinal axisand the plasma chamber longitudinal axis define a sixth angle, the sixth angle between 0° and 30°.

25. The mass spectrometer of claim 24, wherein the sixth angle is between 0° and 20°, 10 more preferably between 0° and 10°, most preferably between 0° and 5°.

26. The mass spectrometer of any of claims 22 to 25, wherein the spray chamber longitudinal axis and the plasma chamber longitudinal axis are substantially parallel.15 27. A method of analysing a sample comprising delivering the sample to the inlet of themass spectrometer of any preceding claim.

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