Optical arrangement for light fragmentation

Abstract

The invention discloses an optical arrangement that splits a light beam into a plurality of beamlets and focuses each beamlet at a respective line. Each line is defined with reference to a respective spatially separated location in at least one dimension such that each beamlet photofragments a different ion defined at the respective location. Each of the spatially separated locations may correspond to a respective capture region of an ion trap in the array of ion traps.

Description

Technical Field

[0001] The present disclosure relates to an optical arrangement for light fragmentation. The optical arrangement can be used in a mass spectrometry system based on an ion trap array.

[0002] CROSS-REFERENCE TO RELATED APPLICATIONS

[0003] This patent application claims priority to U.S. patent application No. 17 / 823,618 filed on August 31, 2022, which is incorporated herein by reference. Background Art

[0004] Mass spectrometry uses the fragmentation of ionized molecules to obtain molecular fingerprints. This facilitates techniques such as tandem mass spectrometry (MS 2 ) or MS n analyze.

[0005] A range of fragmentation techniques are known. One example is photofragmentation or photodissociation (PD), particularly using ultraviolet (UV) or infrared multiphoton (IRM) PD. Examples include: US-10,276,357; US-2016 / 358766; US-9,202,678; US-7,618,806; US-6,342,393; US-6,642,516; US-8,106,353 and WO-2013 / 005060. Further examples include: Payne, AH, Glish, GL., “Thermally assisted infrared multiphotonphotodissociation in a quadrupole ion trap”, Anal. Chem. 73, 3542–3548 (2001); Kim, TY et al., “Peptide photodissociation at 157nm in a linear ion trap massspectrometer”, Rapid Comm. Mass Spectrom. 19, 1657–1665 (2005); Brodbelt, JS, Wilson, JJ, “Infrared multiphoton dissociation in quadrupole ion traps”, MassSpectrom. Rev. 28, 390–424 (2009); Racaud, A. et al., “Wavelength-tunable ultraviolet photodissociation (UVPD) of heparin-derivated disaccharides in a linear iontrap”, J. Am. Soc. Mass Spectrom.20, 1645–1651 (2009); Madsen, JA et al., “Top-downprotein fragmentation by infrared multiphoton dissociation in a dual pressurelinear ion trap”, Anal. Chem. 81, 8677–8686 (2009); and Ly, T., Julian, RR, “Ultraviolet photodissociation: developments towards applications for mass-spectrometry-based proteomics” Angew. Chem. Int. Ed. 48, 7130–7137 (2009).

[0006] refer to Figure 1 , shows an exemplary schematic arrangement of a linear ion trap for photodissociation. The linear ion trap comprises: an RF electrode 10; and an end opening 20. Typically, the laser is located outside the vacuum chamber of the mass spectrometer in which the linear ion trap is located. Special optics, flanges and windows (not shown) are provided to deliver photons to ions 40 via a laser beam 30, which are typically trapped so as to be effectively located in a single point. When the ions are trapped, they are typically irradiated so that multiple pulses can be applied and the resulting fragments can be contained within the same volume.

[0007] Usually, at least or greater than 0.01 J / cm 2 Up to 0.1J / cm 2 A flux of 200 Å is desirable for efficient PD, although for IRMPD it can be increased by several orders of magnitude if the irradiated ions are trapped in a bath gas that can quickly remove the energy deposited into the ions.

[0008] Recently, arrays of mass analyzers have been discussed, including in the following documents: US-5,206,506 (which also suggests the use of IRMPD); US-6,762,406; US-8,203,118; US-9,293,316; US-9,607,817 (also suggesting the use of PD); US-10,199,208; WO-2013 / 092923 (again suggesting the use of PD); and WO-2014 / 176316. The mass analyzer can be separate from the ion trap used for fragmentation. In most cases, collision induced dissociation (CID) is used to fragment the ions in these arrays. Typically, fragmentation of the ions is achieved sequentially.

[0009] It is desirable to improve the implementation of PDs in arrays of mass analyzers, particularly where each mass analyzer is or has an associated respective ion trap. Ion trap arrays have been extensively used in quantum computers and are increasingly used in mass spectrometry. An efficient implementation of PDs may provide significant benefits to such arrays. Summary of the invention

[0010] In this context, an optical arrangement according to claim 1, a light fragmentation system according to claim 14 and a method of processing a light beam for light fragmentation according to claim 20 are provided. Preferred and / or optional features are disclosed in the dependent claims.

[0011] A single laser beam can be split to simultaneously provide corresponding focused laser energy (beamlets) for fragmentation of ions in the ion trap at at least one point in each of a plurality of ion traps in an array. Thus, an optical arrangement is provided for correspondingly splitting a single laser beam. Thus, the high energy of each pulse can be effectively utilized to achieve rapid fragmentation.

[0012] This optical arrangement is advantageously used for ion trap arrays. In particular, each ion trap in the ion trap can have nanometer-scale dimensions, for example, the typical length of the trap is no more than 10mm, and optionally no more than 5mm, 2mm, 1mm or 0.5mm. A specific example of such an ion trap can be a nanometer-scale electrostatic ion trap (μEST, for example as discussed in co-pending and co-assigned U.S. patent application No. 17 / 823618) or an RF trap (for example, as used in a quantum computer). In such an example ion trap array, a single laser pulse with sufficient energy can be generated to fragment the ions across a large number of traps at the same time. In other words, the optical arrangement can provide at least (or more than) 10, 50, 100, 500 or even 1000 beamlets. Ions can be guided into the ion trap in a first direction and / or confined in the ion trap, wherein the light beam (laser beam) is guided perpendicular to the first direction.

[0013] It has therefore been realised that fragmentation in an array of ion traps can be achieved not by addressing each trap individually, but by splitting a (macroscopic) laser beam into an array of matched beamlets, each of which can be aligned with a single trap. Thus, optical fragmentation is scaled to hundreds (and potentially thousands) of ion traps. This, in turn, can allow for increased analytical throughput in these parallel channels.

[0014] The prior art does not take into account the possibility of photofragmentation of multiple ion samples simultaneously in a trap array, especially when the ion traps are of miniature size. In the latter case, there is a significant mismatch between the typical size of the laser beam and the size of the ion beam in the trap, and between the energy or repetition rate of the laser pulses and the required flux or ion residence time.

[0015] One option for achieving the splitting uses a zone plate (using a structure similar to a Fresnel lens, but based on refraction rather than diffraction), which can be in the form of a segmented cylindrical lens (SCL). Other options may include tilted microlens arrays or fiber bundles. In addition to splitting the beam, the optical arrangement also focuses each beamlet onto a plane, and more specifically onto a line. Focusing can be achieved by cylindrical lenses and / or SCLs. In the case where a zone plate is used to split the beam, focusing can be separate from the zone plate, or provided by modifying the front or back surface of the cylindrical lens to integrate the SCL. Two specific implementations of the SCL (or SCL integration) are considered for horizontal splitting and focusing: segments that are symmetrical around the longitudinal (median) plane; and asymmetric segments.

[0016] The arrangements discussed above can be used to split a beam into multiple beamlets in the horizontal dimension or in the vertical dimension. For vertical splitting, a zone plate (which can be implemented as a planar or as a multi-faceted prism) can be provided with a cylindrical lens for focusing. These can be integrated, similar to the horizontal splitting arrangement. Alternatively, an inclined microlens array can provide both splitting and focusing, but with more complex manufacturing. The splitting arrangement in the first (horizontal) direction can be provided together with the splitting arrangement in the second orthogonal (vertical) direction to achieve focused beamlets at points separated in space across two dimensions (each point corresponding to the capture area of ​​a corresponding ion trap).

[0017] Alignment can be achieved by a combination of additional optics for rastering the laser beam (advantageously in two dimensions) and detection pads (preferably four) surrounding the area where the beamlets are to be focused.

[0018] A laser (typically ultraviolet (UV) or infrared (IR)) is advantageously used together with an optical arrangement for light fragmentation. The energy output of the laser is then preferably sufficient to fragment the ions per beamlet. In another sense, the laser and optical arrangement may be configured to achieve at least 0.01 J / cm at each separate location where the ions are defined for fragmentation. 2 of optical flux.

[0019] Implementations of the methods discussed herein can significantly outperform sequentially scanning the laser well by well. Based on the limited rate of, for example, UV lasers (typically <1 kHz to 10 kHz), sequential fragmentation can become too slow and inefficient for a large number of wells in an array.

[0020] It should be noted that various aspects of the present disclosure can be combined. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The present disclosure may be put into practice in many ways and a preferred embodiment will now be described by way of example only and with reference to the accompanying drawings, in which:

[0022] Figure 1 An example schematic arrangement of a linear ion trap for photodissociation is shown;

[0023] Figure 2A shows a plan view of a first exemplary embodiment of an optical arrangement for splitting a laser beam into beamlets along a single dimension;

[0024] Figure 2B shows a plan view of a second exemplary embodiment of an optical arrangement for splitting a laser beam into beamlets along a single dimension;

[0025] Figure 2C shows a plan view of a third exemplary embodiment of an optical arrangement for splitting a laser beam into beamlets along a single dimension;

[0026] Figure 3A illustrates a perspective view of a first segmented cylindrical lens (SCL) in a stacked configuration, the first SCL being configured as a single-dimensional linear array that splits a beam into beamlets along a first dimension;

[0027] Figure 3B illustrates a perspective view of a second SCL in a stacked configuration, the second SCL being configured as a single-dimensional linear array that splits a beam into beamlets along a second dimension;

[0028] Figure 4A shows a plan view of an example SCL and ray traces of the SCL output at a one-dimensional array of focal spots according to an embodiment of the present disclosure;

[0029] Figure 4B depicts an example data set for calculating the center of arc (CoA) position in SCL to achieve a specific focal length;

[0030] Figure 5A A method for producing multiple focal points in a one-dimensional array using a cylindrical lens is schematically shown;

[0031] Figure 5B Shown according to Figure 5A perspective views of example implementations of the method;

[0032] Figure 5C Schematically depicts the Figure 5B A cross section of a facet of a zone plate is shown;

[0033] Figure 5D Schematically shows the Figure 5C A cross section of a multi-faceted prism with facets shown;

[0034] Fig. 6A illustrates a perspective view of a horizontally elongated cylindrical microlens array having tilted axes;

[0035] Figure 6B Shows Fig. 6A Schematic cross sections of some of the cylindrical microlenses of FIG.

[0036] Figure 7 shows a schematic perspective view of an optical arrangement for forming a two-dimensional array of beamlets based on a combination of an SCL and a faceted prism and a cylindrical lens;

[0037] Figure 8 A two-dimensional array of stacked micro electrostatic traps (uESTs) is illustrated; and

[0038] Fig. 9 A perspective view of components on an ion trap with additional features for beam alignment is shown. DETAILED DESCRIPTION

[0039] The focus of the present disclosure is on the photofragmentation or photodissociation (PD) of multiple groups of ions, each group of ions being defined by a respective ion optical device (eg, ion trap). The details of how the ions are trapped are not inevitably relevant for the purposes of the present disclosure.

[0040] U.S. patent application No. 17 / 823618, filed on August 31, 2022 and assigned jointly with the present disclosure, discloses a microelectrostatic trap (μEST) array. The details of this U.S. patent are incorporated by reference. These traps can be formed in one or two dimensions. The array can be large (more than hundreds of traps). Although the present disclosure is well suited for such μEST arrays, it is not limited to such applications. For example, it can be used with other types of ion optical devices or ion trap (including RF trap) arrays. Typically, the size of such ion optical devices or ion traps is small (nanoscale), for example, the length of the trap does not exceed 10 mm and optionally does not exceed 5 mm, 2 mm, 1 mm or 0.5 mm. Additionally or alternatively, the number of ion optical devices or ion traps in the array is typically large, for example at least (or more than) 10, 50, 100, 500 or 1000 devices or traps.

[0041] PD fragmentation of multiple groups of ions is advantageously achieved by emitting a single pulse from a laser, each group of ions being confined within a separate ion optical device or ion trap in an array. Typically ultraviolet (UV) or infrared multiphoton (IRM) lasers are used. The present disclosure provides an optical arrangement that may include a beam splitter arrangement for spatially splitting the laser pulse output into beamlets in different planes. Optionally, a lens array (particularly using micro lenses, optionally with anti-reflective coatings) may be provided for focusing each portion of the pulse into a corresponding collimated beam.

[0042] Thus, in a general sense, an optical arrangement may be considered that is configured to split a beam into a plurality of beamlets and to focus each beamlet at a corresponding line (in a plane). Each line (or each plane) is defined with reference to a corresponding spatially separated position in at least one dimension (generally referred to herein as the z-dimension) such that each beamlet (or each of at least some of the beamlets) photofragmentates a different ion defined at the corresponding position.

[0043] This can additionally (or alternatively) be considered as a method of processing a light beam for photofragmentation, the method comprising: splitting the light beam into a plurality of beamlets; and focusing each beamlet at a corresponding line, each line being defined with reference to a corresponding spatially separated position in at least one (z) dimension, such that each beamlet (or each beamlet in at least some of the beamlets) photofragmentates different ions defined at the corresponding position.

[0044] A number of exemplary optical arrangements and / or methods for achieving this will now be discussed (although reference will be made again below to the general meaning of the above discussion). Although these examples are shown as providing a small number of beamlets (e.g., 5 or 8), it should be understood that this is for illustrative purposes only. These arrangements can be implemented with any number of beamlets, for example, at least or more than 10, 100, 500, or 1000.

[0045] Reference now Figure 2A , a plan view of a first exemplary embodiment of an optical arrangement for splitting a laser beam into beamlets along a single dimension is shown. The optical arrangement 100 includes: a regular cylindrical lens 110; and a segmented cylindrical lens (SCL) 130. A single laser beam 105 is split into beamlets 140 by the optical arrangement 100, each beamlet being focused onto a corresponding capture region of an ion trap array 150. The capture region of the first ion trap 151 defines a first focus, the capture region of the second ion trap 152 defines a second focus, the capture region of the third ion trap 153 defines a third focus, the capture region of the fourth ion trap 154 ​​defines a fourth focus, and the capture region of the fifth ion trap 155 defines a fifth focus.

[0046] The laser beam 105 is first refracted by a cylindrical lens 110 (focusing lens). The cylindrical lens 110 may be a regular plano-convex lens with a curved front surface 111 and a flat rear surface 112. The purpose of this lens is to form a reference (base) focus. The reference (base) focus may be any one of the first to fifth focuses or any intermediate point.

[0047] The SCL 130 is used as a zone plate to focus the beamlets at different focal points. For example, one of the beamlets may be associated with a first focal point (defined by the capture region of the first ion trap 151). In this case, the corresponding segment on the SCL 130 may have a flat surface (no refraction). Other segments on the SCL 130 have a curvature that changes the focal length provided by the lens 110 to form a subset of focal points, such as the second to fifth focal points (defined by the capture regions of the second to fifth ion traps 152-155). This is achieved by segmenting the area on the front or back side of the SCL (zone plate) 130. The areas on the SCL 130 are cut or otherwise physically manufactured (and operated based on refractive properties rather than diffraction). These areas all have equal areas to provide the same photon flux at the corresponding focal points. The power density on each of the lenses should be several orders of magnitude lower than the damage threshold for the lens material (usually, CaF2, MgF2, or quartz glass for UV).

[0048] Nine zones are thereby formed, of which four are mirrored on either side of the central zone 1 121 to form a central beamlet. These zones are: zone 2 122A, 122B, forming two zone 2 beamlets; zone 3 123A, 123B, forming two zone 3 beamlets; zone 4 124A, 124B, forming two zone 4 beamlets; and zone 5 125A, 125B, forming two zone 5 beamlets.

[0049] The SCL 130 is thus customized for multiple focal points (or more specifically, focal lines). In order to define the beamlets 140. The zone 1 beamlets are focused at the capture region of the first ion trap 151. The zone 2 beamlets are focused at the capture region of the second ion trap 152. The zone 3 beamlets are focused at the capture region of the third ion trap 153. The zone 4 beamlets are focused at the capture region of the fourth ion trap 154. The zone 5 beamlets are focused at the capture region of the fifth ion trap 155. The position of the SCL 130 should be precise relative to the focusing lens 110(). This is to match the ray traces after the focusing lens 110 with the segments on the SCL 130.

[0050] It should be noted that providing the cylindrical lens 110 before the SCL 130 allows for simplified manufacturing of curved surfaces in the region on the SCL 130. It can be easier to manufacture and allows for high tolerances for large radii of curvature compared to small radii of curvature. The following quantitative example illustrates how such large radii of curvature result from this implementation.

[0051] For example, the radius of curvature R is defined by (N-1)*F, where N is the refractive index and F is the focal length of the lens. For F=50 mm on a fused silica substrate (N=1.5608 at a wavelength of 193 nm), R=0.5608*50=28.04 mm. This is considered small for physical manufacturing.

[0052] When the regular lens 110 is located in front of the SCL 130, the radius of curvature on the segment can be significantly larger than 28 mm and only slightly different from a flat surface. For example, the farthest focus (corresponding to the capture area of ​​the fifth ion trap 155) can be exactly at the focus of the cylindrical lens 110. Therefore, the corresponding segment on the SCL 130 should have a flat surface with an infinite radius of curvature.

[0053] Assuming that the total number of beamlets is n0, d represents the distance between the cylindrical lens 110 and the SCL 130, and Δ represents the pitch between the focal points (ion traps), the other segments will each have a focal length according to the following formula (f1 represents the focal length of the cylindrical lens 130, and f2(n) represents the focal length of the nth segment of the SCL 130):

[0054]

[0055] Here, f1 is 50 mm, d is 10 mm, Δ = 0.5 mm and n0 = 5, giving (where R n represents the curvature radius of the nth segment of the SCL 130):

[0056] f2(5) = infinity, R5 = infinity (equivalent to a flat surface);

[0057] f2(4)=3960mm, R4=2221mm;

[0058] f2(3)=1960mm, R3=1099mm;

[0059] f2(2) = 1293 mm, R2 = 725 mm; and

[0060] f2(1)=960mm,R1=538mm

[0061] Therefore, when the front lens is not used, the radius of curvature of the segment for the SCL 130 is significantly greater than the value of 28 mm.

[0062] Reference now Figure 2B , a plan view of a second exemplary embodiment of an optical arrangement for splitting a laser beam into beamlets along a single dimension is shown. This is similar in some respects to the first embodiment (although more preferred), and where the same features are shown, the same figure numbers are used. The optical arrangement 200 in this embodiment uses a modified zone plate or focusing lens. The front surface 111 of the focusing lens is a regular cylindrical lens surface. However, the rear surface 212 of the focusing lens is modified. This is shown in the enlarged portion of the rear surface 212. The modification to the rear surface 212 forms a segmented cylindrical lens customized for multiple focal points. In this way, identical beamlets 140 are formed from a single component and can be directed to an array 150. Depending on the modifications made to the rear surface 212, the manufacture of this embodiment may be complicated. The planar rear surface of the focusing lens can make manufacture more straightforward.

[0063] Reference now Figure 2C , shows a plan view of a third exemplary embodiment of an optical arrangement for splitting a laser beam into beamlets along a single dimension. This is also similar to the first embodiment (and more preferred than the first and second embodiments) in some respects, and where the same features are shown, the same figure numbers have been used. The optical arrangement 300 in this embodiment also uses a modified zone plate or focusing lens. However, the front surface 311 is modified from a regular lens and incorporates a segmented cylindrical lens customized for multiple focal points. This is shown in an enlarged portion of the front surface 311. The back surface 112 of the focusing lens is typically planar and simply allows the beamlets 140 to refract at the surface and then be directed to the array 150. The planar rear surface can make it easier to manufacture a lens that is more compact than the front surface 311. Figure 2A and Figure 2B The illustrated embodiment is more straightforward.

[0064] In implementation, it is desirable to split the beam into beamlets in two dimensions. This can be achieved by using stacked SCLs, each stacked SCL being configured to form a single-dimensional linear array of beamlets. Figure 3A , illustrates a perspective view of a first SCL in a stacked configuration that is configured to split a beam into a single-dimensional linear array of beamlets along a first dimension (in this case, along the z dimension as shown).

[0065] SCL 400 is shown as having segments that are symmetrical with respect to the sagittal (median) plane. It comprises: a central segment 401, first outer segments 402A, 402B and second outer segments 403A, 403B. The central segment 401 is thus bounded by the first outer segment labeled 402 (and similarly, the second outer segment 403) on both sides away from the sagittal plane. The segments with the same labeling on both sides of the central segment 401 direct light to the same focal plane. In implementation, any number of outer segments may be provided, but for the purposes of this example, it may be considered that the SCL 400 has seven outer segments on each side of the central segment 401. As described above with reference to Figure 2C As explained, this results in the beamlets being focused at eight locations along a single dimension.

[0066] The beam 410 extends in the x-dimension, perpendicular to the z-dimension (the depth of the SCL 400) and the y-dimension (the width of the SCL 400 across the segments). Thus, the beamlets are focused at lines along the (horizontally) spaced region 450: the center segment 401 is focused at a first line 441; the first outer segments 402A, 402B are focused at a second line 442; and the second outer segments 403A, 403B are focused at a third line 443. The array pitch 455 (the spacing between the lines) is typically 0.4 mm to 0.5 mm.

[0067] Reference now Figure 3B , which illustrates a perspective view of a second SCL in a stacked configuration configured as a single-dimensional linear array of beamlets along a second dimension (in this case, along the x dimension as shown). SCL 500 is shown as having 8 central segments (501, 502, 503, 504, 505, 506, 507, 508) and 2 outer segments (i.e., 10 segments total). Only the 8 central segments are used to split and focus the beam 410. The result of this focusing (as described above with reference to Figure 2C 5 (in question) is a one-dimensional spaced array of beamlets 520. The beamlets 520 are spaced apart in the (vertical) x dimension. The array pitch 525 (the spacing between beamlets) is typically 0.1 mm to 0.5 mm, or more typically 0.4 mm to 0.5 mm.

[0068] As a guide, the size of each lens of each SCL can vary from about 10 mm x 10 mm to about 40 mm x 40 mm. The size of each cell or ion trap (and therefore the spacing between cells) can vary from 50 μm to 5 mm. The positioning accuracy of the beamlets can range from 5 μm to 200 μm. Figure 3A and Figure 3BThe two elements of the CMOS operate in two orthogonal planes, so there is a certain degree of independence between them. Standard alignment procedures using micro-positioning stages (with an accuracy of about tens to hundreds of microns) may be sufficient.

[0069] The result of stacking the first SCL 400 and the second SCL 500 is to form a two-dimensional array of focal spots. In this specific example, an 8x8 array of beamlets can thus be provided. Figure 3A and Figure 3B The SCL shown can therefore be considered as a three-dimensional building block to form a two-dimensional array of foci.

[0070] A further explanation of the construction of an SCL for providing a one-dimensional array of foci is now provided. In this regard, reference is made to Figure 4A , which shows a plan view of ray traces of an example SCL and a one-dimensional array of foci output according to an embodiment of the present disclosure. The foci are labeled F1-F8, each of which will match the center of a corresponding ion optical device or ion trap (e.g., a corresponding μEST unit).

[0071] In this example, the SCL 600 includes eight segments 601, 602, 603, 604, 605, 606, 607, 608 arranged around a central axis 610. The height h of the segments in the SCL 600 and the bottom thickness t of the SCL 600 are marked.

[0072] This arrangement differs from Figure 3A The SCL shown in FIG. 600 does not have segments arranged symmetrically around the longitudinal plane. Each segment is a source for a unique focal plane. This allows a reduction in the number of physical segments (compared to Figure 2A , Figure 2B and Figure 2C ) compared to those shown, but allows a higher number of functional elements. This can improve manufacturability. In the SCL 600, the center plane is not a symmetry plane. Therefore, a sequence of segments with continuously varying radii is produced on the lens. This can avoid significant overlap between adjacent beamlets and thereby reduce interference from beamlets entering adjacent cells. Therefore, compared to e.g. FIG. 2A to FIG. 3B This sequence may be preferred compared to the sequence shown.

[0073] The ray paths 620 from the front face 611 of the SCL 600 to the respective focus points F1-F8 for each segment are shown with solid lines for segments 603, 606, 607 and 608. Dashed lines 630 connect the respective edges on the front face 611 of each segment to the respective arc centers of segments C1-C8. These are labeled with radii R1-R8 (each a radius of curvature). For segments p above the centerline (even-numbered segments), the centerline 610 is aligned with the farthest R1. pThe angle between them is marked as α p , and the center line 610 is closest to the R p The angle between is marked as β p For the segment q below the center line (odd segment), the center line 610 is at the farthest R q The angle between them is marked as γ q , and the center line 610 is closest to the R q The angle between them is denoted as δ q It is desirable to define these angles accurately.

[0074] In the case of n=4 (and where t represents the bottom thickness of SCL 600), the formula for the edge segment: angles α, β, γ, δ and arc center position C 2n and C 2n-1 This is given by the following expression, so that the total number of segments is 2*n=8.

[0075]

[0076] For even-numbered segments angle α 2k ,β 2k (above centerline 610), the angle satisfies the following expression.

[0077] R 2k *sinα 2k = k*h, k = 1…4 (5)

[0078] R 2k *sinβ 2k =(k-1)*h, k=1…4 (6)

[0079] For odd-numbered segments angle γ 2m-1 ,δ 2m-1 (below centerline 610), the angle satisfies the following expression.

[0080] R 2m-1 *sinγ 2m-1 =m*h, m=1…4 (7)

[0081] R 2m-1 *sinδ 2m-1 =(m-1)*h, m=1…4 (8)

[0082] Based on the geometric relationships described in detail previously, the following expressions can be determined.

[0083] R 2k *cosβ 2k -R 2k-2 *cosα 2k-2 =C 2k -C2k-2 (9)

[0084] R 2m-1 *cosδ 2m-1 -R 2m-3 *cosγ 2m-3 =C 2m-1 -C 2m-3 (10)

[0085] Therefore, a loop formula can be defined to find the arc center (CoA or center of curvature) position starting from the edge segments on both sides. The CoA position for even segments is given by formula (11), while the CoA position for odd segments is given by formula (12).

[0086] C 2k-2 =C 2k +R 2k-2 *cosα 2k-2 -R 2k *cosβ 2k (11)

[0087] C 2m-3 =x 2m-1 +R 2m-3 *cosγ 2m-3 -R 2m-1 *cosδ 2m-1 (12)

[0088] To determine the design of the SCL, the geometry of the focal array to be produced is first considered. Then, practical design aspects are identified, such as: (1) the distance from the physical elements of the optics to the location of the focal array; and (2) the manufacturability of the multiple curved surfaces of the optic. The first aspect reflects geometric constraints, such as interference from other design elements. By default, a range of 10 mm to 100 mm is assumed to be safe to avoid those interferences. When a small focal size is required, a relatively small focal length (less than 100 mm) may be beneficial. In some cases, a focal length in the range of about 80 mm may be appropriate. There may be a tradeoff between interference and focal size. From a manufacturability perspective, it is desirable that the radius of the curved surface should be manufacturable.

[0089] For example, it may be desirable to provide an 8x8 element beamlet array with a focal pitch of 0.5 mm in both axes. Figure 2CThe geometry shown can be used to form a one-dimensional array of focal points located along the optical z-axis. A 30 mm x 30 mm cylindrical lens can be well suited to the size of the beam after the beam expander. Many commercial cylindrical lenses have this or similar dimensions. For a segment width of 3 mm and 8 elements, the segmented portion of the lens can take 8 mm x 3 mm = 24 mm. The rest of the lens area (3 mm on each side) can be reserved for mounting the lens in a holder.

[0090] It should be noted that as the width of each segment decreases, it becomes more challenging to form undercuts between segments, leading to finer manufacturing. A segment width of 3 mm should be adequate for processing. More generally, the segment width is ideally in the range of 0.5 mm to 5 mm. The lens bottom width or thickness (t) has been assumed to be 5 mm, particularly since this is a standard based on optics catalogs.

[0091] For the purposes of the following calculations, a plano-convex geometry is assumed for all segments. Other shapes are possible, such as optimal shape lenses, but these can be more complex and expensive.

[0092] Next reference Figure 4B , depicts an example data set for calculating the CoA position in the SCL to achieve a specific focal length. The example calculation is for a total of 8 segments on the lens, where the pitch step (distance x1-x2, x2-x3, x3-x4, etc.) is 0.5mm. Other parameters for this example include: material of fused silica; refractive index, N=1.5608 at a wavelength of 193nm; segment width, h=3mm; bottom thickness t=5mm. In this example case, the lens size is approximately 30mm×30mm. In order to calculate the CoA position, the focal length F1,…,F8 650 (column C) is first determined according to the defined pitch step.

[0093] Check Figure 4A The first section 601 shown may assume a plano-convex configuration. Define the focal length as f, the radius of curvature as R, and the refractive index as N, and the relationship between the radius of curvature and the focal length is defined by the following formula:

[0094] R=F*(N-1) (13)

[0095] For a typical R value (e.g., 46 mm), the focal length can be calculated to be 82.03 mm. For N, its value at a wavelength of 193 nm is used, which is equal to 1.5608 (material - fused silica). All other focal lengths for other segments can be set using a design-defined pitch of 0.5 mm. The remaining radius R1, ..., R8 660 (column E) is then calculated accordingly. The resulting value is no higher than 48 mm, which is very normal in industrial standards. Lenses of similar radius can be routinely found in optical product catalogs, so it is believed that such lenses can be easily manufactured.

[0096] Finally, the angles and CoA 670 (column O) can be determined using equations (1)-(12). The shape of each arc on the lens can be established by defining its center location and the start and end points. When the center of each arc is calculated and the radius is known, the arc can be completely defined by the start angle δ and the end angle γ. For example, angles δ3 and γ3 are for segment 603 ( Figure 4A ). It should be noted that for segments 601 and 602, only one angle is required.

[0097] The process starts with an edge segment, which in this case is Figure 4A The segments 607 and 608 shown are shown. First, the angles α8 and γ7 are calculated according to formulas (1) and (2). Then, the arc center positions C8 and C7 are calculated according to formulas (3) and (4). The remaining angles are calculated using formulas (5) to (8). All these angles are Figure 4B For convenience, the angles are shown in both degrees and radians.

[0098] Finally, the angles α, β, λ and δ calculated above and the values ​​C7 and C8 calculated in equations (11) and (12) are used to calculate arc centers C1-C6 for segments 1 to 6. The center position, radius, start angle and end angle are now defined for each arc.

[0099] See now Figure 5A , which schematically illustrates a method for using cylindrical lenses to produce multiple focal points in a one-dimensional (vertical) array. The method forms beamlets with multiple spatial frequencies and / or angles, for example using a plane zone plate, which may also be referred to as a multi-faceted prism (as described below with reference to Figure 5B Discussed). A central x-axis and orthogonal y-axis are shown, and the paraxial approximation is assumed.

[0100] The cylindrical focusing lens 710 is positioned parallel to the y-axis and centered on the x-axis. The wavefront (θ) of the first beamlet 701 for a first angle with the x-axis is shown. x1 ) and the wavefront (θ) of the second beamlet 702 at a second smaller angle to the x-axis x2). The focusing lens 710 focuses the first beamlet 701 to provide a first focused beamlet 720, which is focused at a first horizontal line B1 with a first displacement Δ1 along the y-axis. Similarly, the focusing lens 710 focuses the second beamlet 702 to provide a second focused beamlet 730, which is focused at a second horizontal line B2 with a first displacement Δ2 along the y-axis. Thus, a one-dimensional vertical array of focal lines is generated.

[0101] This method exploits the fact that when a parallel beam enters the lens at an angle, the focus for the beam is not on the optical axis but is displaced. If the input beam comprises a series of parallel beams that hit the focusing lens 710 at different angles, there are several focal points in the focal plane, where the displacement is proportional to the angle of incidence and the focal length of the lens. In other words, the displacement of the nth beamlet along the y-axis (from the x-axis) is given by the following expression.

[0102] Δ n =f*Θ xn (14)

[0103] This opens the way to create an array of focal spots featuring regular spacing between the focal spots. The beam is split into subsets of individual beamlets that enter the lens at different angles. A number of options for thus forming an array of vertical beamlets are now discussed.

[0104] Next reference Figure 5B , showing that according to Figure 5A 700; and a cylindrical lens 710. Eight different beamlets are shown: four beamlets above the x-axis O (labeled 1, 2, 3, 4); and four beamlets below the x-axis O (labeled -1, -2, -3, -4).

[0105] Thus, the multi-faceted prism 700 has a number of facets equal to the number of beamlets required. The angled surfaces of the prism 700 are flat. In this figure, 8 beamlets are shown. The cylindrical lens 710 collects the individual beamlets into a focal point. The calculations for each facet can be performed as follows. First, the focal length f can be selected for the cylindrical lens based on the design non-interference requirements, especially the proximity to other construction elements and / or lenses. An exemplary calculation can be performed with f=50 mm. This can be selected so that Figure 5A The components are placed in Figure 2C Between the lens and the object plane shown. Figure 2C The focal length of the segments in may be about 80 mm, so for the second vertical arrangement f=50 mm may be safe. The prism 700 and cylindrical lens 710 may have a form factor of about 30 mm x 30 mm.

[0106] Then, assuming that the equidistant positions of the foci have a step size Δ=Δ2-Δ1=Δ3-Δ2=Δ4-Δ3, etc., the above formula (14) thus allows for the angle θ of each beamlet to be xi The calculated value of . Using the calculated angle Θ xi , the angle α can be calculated for each small face i .

[0107] Next reference Figure 5C , schematically depicting the Figure 5B A cross section of a facet of a zone plate 700 is shown, showing beamlet paths according to the angle of the front surface 705 of the facet of the zone plate 700. An example beamlet 750 is directed at the front surface 705 of the facet of the zone plate 700. An angle α of the nth facet at the back surface of the zone plate facet (prism) with the vertical (y) axis is shown. n and the beamlet angle Θ with the x-axis n The calculation of these angles for each facet can be determined according to the following expressions.

[0108] sinΘ n =n*sin(α n -β n ) (15)

[0109] sinα n =n*sinβ n (16)

[0110] The pair of equations (15) and (16) can be solved simultaneously to eliminate the angle β. This allows the angle θ at which the beam is deflected from the optical axis to be determined according to the expression xi Angle α with the small face i The relationship between.

[0111]

[0112] A simplified form of this formula can be found for paraxial optics.

[0113]

[0114] An exemplary calculation for 8 facets or zones is now discussed based on the following assumptions: focal length f = 50 mm; prism made of fused silica has a refractive index N = 1.5608; symmetry exists in the spur plane of the zone plate. Figure 5D These angles are described in detail, based on Figure 5C The facets shown schematically illustrate a multi-faceted prism 700 in cross section. The angle α of each facet with the vertical (y) axis is shown. iSince the multi-faceted prism 700 is symmetric about the x-axis, the angles are also symmetric.

[0115] The angle can be determined based on the following expression:

[0116] Δ=h / (2f) (19),

[0117] Where h is the distance between fragmentation locations (eg, between cells in an ion trap array, each ion trap may be μEST), and f is the focal length of cylindrical lens 710 .

[0118] In one example, assume h = 0.5 mm, f = 50 mm and n = 1.5608. Then, the angle α relative to the vertical (y) axis is i (in radians) are as follows:

[0119] α1=α -1 =Δ / 2 / (n-1)=0.0045 rad=0.26 degrees;

[0120] α2=α -2 =3 / 2Δ / (n-1)=0.013 rad=0.77 degrees;

[0121] α3=α -3 =5 / 2Δ / (n-1)=0.23 rad=1.28 degrees;

[0122] α4=α -4 =7 / 2Δ / (n-1)=0.031 rad=1.79 degrees.

[0123] All of these angles are small (less than 2 degrees), making the paraxial optical approximation valid.

[0124] Planar zone plates or multi-faceted prisms can be manufactured more directly than other implementations due to the flat surfaces of the prisms. However, this combination with a cylindrical lens (or equivalent) therefore requires two optical elements, which may need to be precisely aligned near the target array. Another variation of this approach can be a mirror array, including the digital micromirror device sold by Texas Instruments Inc.

[0125] An alternative approach can be based on a cylindrical microlens array. In this case, no separate prism and focusing lens are required, as a single optical setup can be used. Fig. 6A , illustrates a perspective view of a horizontally elongated cylindrical microlens array with tilted axes to form beamlets at multiple focal points in a one-dimensional (vertical) array. In this specific example, 8 focal points are shown. Similar to Figure 3AThe SCL array 800 has eight microlenses (801a, 802a, 803a, 804a, 801b, 802b, 803b, 804b) for splitting and focusing the beam 810. However, this design is different from Figure 2C and Figure 3A There are some differences between the designs shown. Fig. 6A In the design of , all segments have the same radius of curvature, which means that the focal length of all segments is the same. For comparison, Figure 2C The curvature radius of the SCL segments is different (as shown in the above reference Figure 4B Furthermore, the optical axes of these segments are tilted at an angle similar to the angle calculated in equation (18) above, as will be discussed below.

[0126] The result of this focusing is a one-dimensionally spaced array of beamlets 820 spaced in the (vertical) x dimension. The array pitch 825 (the spacing between beamlets) corresponds to the cell size and is typically 0.1 mm to 0.5 mm. Figure 5B The layout is different. Fig. 6A The cylindrical microlens 800 of SCL requires only one optical element, but is much more complex and has high requirements for the accuracy of each lens. The desire to accurately set both the exact lens profile (curvature of a specific radius) and the exact lens tilt angle makes the array 800 more difficult to implement than SCL.

[0127] Then refer to Figure 6B , showing Fig. 6A Schematic cross-section of some of the cylindrical microlenses of FIG. 1 , and more clearly showing the tilt axis. The tilt angle of the cylindrical microlens is given by the following expression, where h is the distance between the fragmentation locations (as discussed above), and f is the focal length of the microlens.

[0128] sin(α1)=h / (2*f);

[0129] sin(α2)=3h / (2*f);

[0130] sin(α3)=5h / (2*f);

[0131] sin(α4)=7h / (2*f).

[0132] It should be understood that α1 is the tilt angle for microlens 801a, α2 is the tilt angle for microlens 802a, α3 is the tilt angle for microlens 803a, and α4 is the tilt angle for microlens 804a. The tilt angle for microlens 801b is α-1 equal to α1, the tilt angle for microlens 802b is α-2 equal to α2, the tilt angle for microlens 803b is α-3 equal to α3, and the tilt angle for microlens 804b is α-4 equal to α4.

[0133] Using the assumptions of the above example, where h = 0.5 mm and f = 50 mm, these angles can be calculated as follows.

[0134] α1=α -1 = 0.005 rad = 0.29 degrees;

[0135] α2=α -2 = 0.015 rad = 0.86 degrees;

[0136] α3=α -3 = 0.025 rad = 1.43 degrees; and

[0137] α4=α -4 =0.035 rad=2.01 degrees.

[0138] Reference now Figure 7 , which shows the use of SCL-based (such as Figure 2C ) and multi-faceted prisms and cylindrical lenses (as shown Figure 5B Schematic perspective view of an optical arrangement for forming a two-dimensional array of beamlets by combining a plurality of parallel beams 900 (shown in Figure 3) to form a two-dimensional array of beamlets. This can be relatively straightforward to manufacture. It can be seen that a parallel beam 900 passing through an SCL 300 provides an array of horizontal focal points 910 (only the first three are shown), and a faceted prism with a cylindrical lens then adds vertical focal points 920 (three on either side of the center are shown). The result is a two-dimensional array of focal points with a corresponding beamlet focused at each focal point.

[0139] Alternative optical arrangements for splitting the beam and focusing the beamlets may be considered. For example, an arrangement based on a fiber optic bundle will be described in further detail below.

[0140] Returning to the general sense discussed above, preferably further optional and / or advantageous features may be considered, as will now be presented.

[0141] For example, the optical arrangement may include a zone plate (formed by a lens arrangement based on a Fresnel lens structure) configured to split the light beam into multiple beamlets. The zone plate may be planar or made as a segmented cylindrical lens (SCL) or a multi-faceted prism.

[0142] The optical arrangement may further include a cylindrical lens configured to receive and refract the beam or beams. A zone plate may be integrated with the cylindrical lens. The zone plate (which may include an SCL portion) may be configured to focus each beamlet at a corresponding plane, and the integration of the cylindrical lens with the zone plate may be achieved by adapting the front and / or rear surfaces of the cylindrical lens.

[0143] In the case where the zone plate is formed by an SCL section configured to focus each beamlet at a respective plane, the SCL section may have segments that are symmetrical about the sagittal (center plane) plane. In this case, segments equidistant from the sagittal plane may be used to focus the beamlets at a common plane. Alternatively, the SCL section may have segments that are asymmetrically arranged. Each segment may then focus the beamlets at a different respective plane.

[0144] In an embodiment, the optical arrangement may include a tilted microlens array configured to split the light beam into a plurality of beamlets and focus each beamlet at a respective plane.

[0145] In an embodiment, the optical arrangement may include an optical fiber bundle configured to split the light beam into a plurality of small beams. The optical arrangement may also include an array of lenses (particularly microlenses), each lens being aligned with a corresponding optical fiber of the optical fiber bundle to focus a corresponding small beam at a corresponding plane.

[0146] The first portion of the optical arrangement is advantageously configured to split the beam in a first direction, e.g., horizontally (this can be a direction parallel to the width of the first portion (which can be the y dimension) or a direction perpendicular to the width of the first portion (which can be the depth or z dimension)). This can allow each beamlet to be focused at a line spaced apart from the other lines along the first direction. In an embodiment, the first portion is formed by a first zone plate, which can also include a cylindrical lens or SCL portion. Other options for the first portion may include those discussed above (or elsewhere herein).

[0147] The second portion of the optical arrangement may be configured to split the beam in a second direction (e.g., a vertical or x-dimension) orthogonal to the first direction. This may allow each beamlet to be focused at a point spaced apart from the other points in the second direction (thereby splitting and focusing the beam in two dimensions). Advantageously, the second portion is arranged to receive the optical output from the first portion (although the opposite arrangement is possible in some specific implementations). In one option, the second portion may be formed by a second zone plate and a cylindrical lens portion. According to this option, in some embodiments, the cylindrical lens portion may be integral with the second zone plate. For example, the zone plate may be in the form of a multi-faceted prism having a cylindrical lens integrated into its front surface. The multi-faceted prism may then have a flat angled rear surface. According to a second option, the second portion may be formed by a tilted microlens array. Other options for the second portion may include those discussed above (or elsewhere herein).

[0148] Reference now Figure 8 , illustrating a two-dimensional array of stacked micro electrostatic traps (uESTs). These correspond to the disclosure of U.S. Patent Application No. 17 / 823618 filed on August 31, 2022. In this example, an 8×8 array of uESTs is shown. The direction of the optical beamlet (UV) 1000 for light fragmentation and the direction of the ion beamlet 1010 entering the μEST module 1020 (each μEST module has 8 traps) are shown. It can be seen that eight such μEST modules 1020 are shown. They are mounted on a motherboard chip 1030.

[0149] Each μEST module 1020 includes: at least one double-sided μEST chip 1021; a spacer chip 1022. The μEST module 1020 at the end of the array has a double-sided μEST chip 1021 and an end-piece μEST chip 1023, while the other μEST modules share two double-sided μEST chips 1021. At the base of each μEST module 1020, rear contact pads 1024 are provided on the spacer chip 1022. These are coupled to contact pads 1025 on the motherboard chip 1030. The through-wafer deep reactive ion etched (DRIE) slots 1035 in the motherboard chip 1030 accommodate eight spacer chips 1022.

[0150] The optical beamlets 1000 provided to the μEST array can be generated by the optical arrangement proposed in this paper, for example 8 rows of wells, with 8 wells in each row. For the sake of completeness, please note that Figure 7 and Figure 8 The 90 degree orientation difference between the two is indicated by the x- and y-arrows. The dimensions of the optical components are ideally matched to the pitch of the ion trap in each direction. If the pitch needs to be adjusted due to tolerances, additional optics can be used.

[0151] It can therefore be seen that a two-dimensional array of ion trap positions is provided by the μEST module 1020 (in the xz plane). By raster scanning the ion beam in the x and z directions, ions in the ion beam parallel to the y dimension can be introduced into any ion trap in the ion trap. The light beam (laser beam) 1000 is introduced from the side (parallel to the z dimension) and the two-dimensional (xz) array of focal points is aligned with the two-dimensional array of ion trap positions. It can also be understood that a one-dimensional array of focal lines can be aligned in this manner alternatively. Any coating of the optical arrangement discussed above is possible. Anti-reflection coatings can be optionally used to reduce losses (up to 4% loss can be generated each time the surface passes). This can be applied to one, some or all elements, lenses and prisms. This can be particularly useful for multi-lens arrangements.

[0152] In this case, alignment of the beamlets with the fragmentation sites in each ion trap is particularly advantageous. Fig. 9 An exemplary method for two-dimensional (x, y) alignment is discussed, wherein a perspective view of components on an ion trap with additional features for beam alignment is shown. The ion trap includes: a first (upper) electrode 1110; and a second (lower) electrode 1120. Ions are trapped in a trapping region between the first electrode 1110 and the second electrode 1120. The electrodes 1110, 1120 are typically formed on adjacent integrated circuits (or chips), such as Figure 8 As shown. For the purpose of light fragmentation, a laser beam (or more precisely, a beamlet) 1100 is directed into the capture region. As shown, alignment in the x-direction and y-direction is ideal for improving fragmentation efficiency and effectiveness.

[0153] Using detection pads can help correct alignment. Specifically, four detection pads are shown in this example: a first detection pad 1111 on the first electrode 1110; a second detection pad 1112 on the first electrode 1110; a third detection pad 1121 on the second electrode 1120; and a fourth detection pad 1122 on the second electrode 1120. It is desirable that the detection pads be positioned near the optimal position of the laser beam 1100 on the leading edge of the ion trap electrode.

[0154] Additional optics (not shown) may then be used to raster the laser beam 1100, preferably at the milliradian level in both the x- and y-dimensions. Doing so may allow the photoelectron signal to be detected sequentially on each of the pads 1111, 1112, 1121, 1122 by an electrometer (not shown). Based on the timing, duration, and rise time of the signal, the actual beam size and position in the operating mode may be established. The laser beamlet 1100 may then be directed to the target location 1130 accordingly.

[0155] This method can provide initial beam alignment on the target. Alternatives are possible. For example, Figure 2C Place a mask on all components on the SCL300 (reference Figure 7 ). Similar masks can be applied to Figure 5A (and / or Figure 7 A) shows a multi-faceted prism 700. After masking, only one element can be active. With this single element illuminated by the laser, a micropositioner (with a stepper motor to count steps for x- and y-displacement) can be used to pass through all four pads 1111, 1112, 1121, 1122.

[0156] A camera and register can then be used to detect when the laser hits each pad one after another, counting the steps in both directions. The design geometry dictates how the pad positions refer to where the ions are expected to arrive. Fig. 9 The step counts for the x1, x2, y1, y2 positions are shown to count the steps of the target 1130.

[0157] In the case of the μEST array, the ions can be illuminated at their turning points as they oscillate inside each of the ion traps. If all the ions of interest reach their turning points at the same time, a single laser pulse may be sufficient to provide sufficient flux for fragmentation. However, if the ions are not synchronized, multiple pulses can be used so that every ion in the final trap is fragmented.

[0158] In a typical example, a laser beam with a diameter of 2mm to 3mm and an energy of 5mJ to 10mJ is directed to an 8×8 well array with 0.5mm spacing in the x- and z-directions. With a 20 micron ion beam size, 1J / cm2 can be achieved in each of the 64 wells, even with 5x to 10x photon losses in the optics. 2 The flux.

[0159] In addition to the alternative embodiments based on digital micromirror devices already mentioned, embodiments based on fiber bundles terminated with microlens arrays can also be envisioned. Each lens of the microlens array can typically have a diameter of less than one millimeter, and typically as small as 10 μm. The pitch of the fiber bundle and the pitch of the microlenses are advantageously matched to the pitch of the ion trap array. In this case, the same effects as described above can be achieved for lenses and zone plates based on the Fresnel principle.

[0160] According to further summarized aspects of the present disclosure, a light fragmentation system can be considered, which includes: an optical arrangement as disclosed herein; and an ion trap array, each of the spatially separated positions corresponding to a corresponding capture area of ​​one of the ion traps. Preferably, the ion trap is a μEST or RF trap. In an embodiment, the ion trap has parallel longitudinal axes and / or axes for receiving ions, and laser and optical pulses are applied in directions orthogonal to the longitudinal axes and / or axes for receiving ions. Each ion trap can be formed by one or more planar electrode arrangements, for example formed on a chip (or other type of integrated circuit). The array can be formed by stacked chips and / or the longitudinal axis can be defined by the corresponding chip.

[0161] The ion traps in the array are typically arranged in two dimensions. The optical arrangement can then be configured to focus each beamlet at a corresponding point in two dimensions. Each point corresponds to a corresponding capture region of one of the ion traps in the ion trap array.

[0162] Each ion trap may include detection pads located around the area where the beamlets are to be focused. For example, four detection pads may be provided. The detection pads may be located on portions of the electrodes of the ion trap, for example on a surface of the ion trap close to where the beamlets arrive (which may be perpendicular to the surface of the electrode defining the extent of the capture area). The ion fragmentation system may then further include: additional optics configured to rasterize the laser beam (preferably in two dimensions) so that the detection pads detect the rastered beamlets; and a controller configured to align the beamlets based on output from the detection pads. Corresponding methods of beamlet alignment may also be considered.

[0163] The photofragmentation system also typically includes a laser configured to emit pulses at the optical arrangement for processing. Advantageously, the energy output of the laser is sufficient to cause each beamlet to photofragment the ions. Additionally or alternatively, the laser and the optical arrangement may be configured to achieve at least 0.01 J / cm at each of the plurality of locations. 2 of optical flux.

[0164] Although embodiments according to the present disclosure have been described with reference to specific types of devices and applications (specifically, mass spectrometry) and these embodiments have specific advantages in this context, as discussed herein, methods according to the present disclosure may be applied to other types of devices and / or applications. In particular, devices according to the present disclosure may be used in other applications, particularly in the case of light fragmentation or light dissociation using multiple beams (beamlets). The specific structure, arrangement, and operating details (e.g., parameters) of the processes described herein, although they may be advantageous (especially in view of known configurations and capabilities), may vary greatly to achieve an operating mode with similar or identical performance. Other types of beam splitters and / or focusing may be considered from those disclosed herein. Certain features may be omitted or replaced, for example as shown herein. Unless otherwise stated, each feature disclosed in this specification may be replaced with an alternative feature for the same, equivalent, or similar purpose. Therefore, unless otherwise stated, each feature disclosed is merely an example of a series of equivalent or similar attribute features.

[0165] Embodiments are described in which the front or rear surface of a zone plate is modified to integrate an SCL. This is because the optical industry typically processes optical element lenses precisely when their opposing surfaces have the same spherical symmetry. Thus, the examples described herein may be implemented with a double commercial symmetrical convex / concave lens (same radius of curvature on opposite sides) or a so-called best form lens (different radius of curvature on opposite sides). Cylindrical lenses typically have only one non-flat surface. However, it is possible to achieve the same result (significantly more difficult and not easy to manufacture) by modifying both the front and rear surfaces. In other words, a combination of profiles on opposing sides of a single optical element may be possible.

[0166] In the detailed description of various embodiments, for the purpose of explanation, many specific details are set forth to provide a thorough understanding of the disclosed embodiments. However, those skilled in the art will appreciate that these various embodiments may be practiced with or without these specific details. Furthermore, those skilled in the art can readily appreciate that the specific order in which the methods are presented and executed is illustrative, and it is contemplated that the order may be changed and still remain within the scope of the various embodiments disclosed herein.

[0167] As used herein, including in the claims, unless the context indicates otherwise, the singular form of the terms herein should be interpreted as including the plural form, and vice versa. For example, unless the context indicates otherwise, a singular reference herein (including in the claims), such as "one / kind" (such as an ion multipole device) means "one or more" (for example, one or more ion multipole devices). In the specification and claims of the present disclosure, the words "include", "comprising", "having" and "containing" and variations of these words, for example, "including" or similar words mean "including but not limited to", and are not intended to (and do not) exclude other components. In addition, the use of "or" is inclusive, so that when "A" is true, "B" is true, or "A" and "B" are both true, the phrase "A or B" is true.

[0168] The use of any and all examples or exemplary language ("for example," "such as," "for example," and similar language) provided herein is intended to merely better illustrate the present disclosure and does not indicate a limitation on the scope of the present disclosure unless otherwise required. No language in this specification should be construed as indicating any non-claimed element essential to the practice of the present disclosure.

[0169] The terms "first" and "second" can be reversed without changing the scope of the present disclosure. That is, an element referred to as a "first" element can instead be referred to as a "second" element, and an element referred to as a "second" element can instead be considered a "first" element.

[0170] Unless otherwise specified or the context requires otherwise, any steps described in this specification may be performed in any order or simultaneously. In addition, where a step is described as being performed after a step, this does not exclude intermediate steps being performed.

[0171] It should also be understood that, unless otherwise implicitly or explicitly understood or stated, for any given component or embodiment described herein, any possible candidate or alternative listed for that component may generally be used alone or in combination with each other. It should be understood that any list of such candidates or alternatives is merely illustrative and not restrictive, unless otherwise implicitly or explicitly understood or stated.

[0172] All literature and similar materials cited in this disclosure (including but not limited to patents, patent applications, articles, books, treaties, and internet web pages) are expressly incorporated by reference for any purpose. Unless otherwise defined, all technical and scientific terms used herein have the meaning commonly understood by one of ordinary skill in the art to which the various embodiments described herein belong.

Claims

1. An optical arrangement configured to split a light beam into a plurality of beamlets and focus each beamlet at a corresponding line, each line being defined with reference to a corresponding spatially separated position in at least one dimension, so that each beamlet in at least some of the beamlets optically fragments different ions defined at the corresponding position.

2. The optical arrangement of claim 1 , further comprising: A zone plate is configured to split the light beam into the plurality of beamlets.

3. An optical arrangement according to claim 2, wherein the zone plate is planar or is made as a segmented cylindrical lens (SCL) or a multi-faceted prism.

4. An optical arrangement according to claim 2 or claim 3, further comprising: A cylindrical lens is configured to receive and refract the beam or the beamlets.

5. The optical arrangement of claim 4, wherein the zone plate is integral with the cylindrical lens.

6. An optical arrangement according to claim 5, wherein the zone plate is configured to focus each beamlet at the corresponding line, and the integration of the zone plate with the cylindrical lens is achieved by adaptation of the front surface or the back surface of the cylindrical lens.

7. An optical arrangement according to any preceding claim, wherein the zone plate is fabricated as a SCL, and wherein the SCL has sections that are symmetrical about a sagittal plane.

8. An optical arrangement according to any preceding claim, wherein the first part of the optical arrangement is configured to split the beam in a first direction such that each beamlet is focused at a line spaced apart from other lines in the first direction.

9. An optical arrangement according to claim 8, wherein the first portion is formed by a first zone plate.

10. An optical arrangement according to claim 8 or claim 9, wherein the second part of the optical arrangement is configured to split the beamlets in a second direction orthogonal to the first direction so that each beamlet is focused at a point spaced apart from other points in the second direction.

11. An optical arrangement according to claim 10, wherein the second portion is formed by a second zone plate and a cylindrical lens portion, or wherein the second portion is formed by an array of tilted micro lenses.

12. An optical arrangement according to claim 10 or claim 11, wherein the second portion is formed by a cylindrical lens portion integral with a second zone plate.

13. An optical arrangement according to claim 12, wherein the zone plate is in the form of a multi-faceted prism, wherein the cylindrical lens is integrated into the front surface and the flat inclined rear surface of the multi-faceted prism.

14. A light fragmentation system, comprising: an optical arrangement configured to split the optical beam into a plurality of beamlets and to focus each beamlet at a respective line, each line being defined with reference to a respective spatially separated position in at least one dimension, such that each beamlet of at least some of the beamlets photofragmentates a different ion defined at the respective position; and An ion trap array, each of the spatially separated locations corresponds to a respective capture region of one of the ion traps.

15. The light fragmentation system of claim 14, wherein the ion trap array is arranged in two dimensions and the optical arrangement is configured to focus each beamlet at a respective point in the two dimensions corresponding to a respective capture region of one of the ion traps.

16. A light fragmentation system according to claim 14 or claim 15, wherein The ion trap is a μEST or RF trap; and / or The ion trap has a parallel longitudinal axis and / or axis for receiving ions, and the light beam is applied in a direction orthogonal to the longitudinal axis and / or axis for receiving ions.

17. The optical fragmentation system of any one of claims 14 to 16, wherein at least one ion trap or at least one row of ion traps in the ion trap array comprises detection pads located around the area where the beamlets are to be focused, the optical fragmentation system further comprising: additional optics configured to rasterize the beam such that the detection pad detects the rastered beamlets; and A controller is configured to align the beamlets based on output from the detection pad.

18. The light fragmentation system according to any one of claims 14 to 17, further comprising: An ultraviolet or infrared laser configured to emit the light beam at the optical arrangement.

19. The light fragmentation system of claim 18, wherein: The laser has an energy output sufficient to cause each beamlet to photofragment the ions; and / or The laser and the optical arrangement are configured to achieve at least 0.01 J / cm at each of the spatially separated locations. 2 of optical flux.

20. A method of processing a light beam for light fragmentation, the method comprising: splitting the light beam into a plurality of beamlets; as well as Each beamlet is focused at a respective line, each line being defined with reference to respective spatially separated positions in at least one dimension, such that each beamlet in at least some of the beamlets photo-fragmentates different ions defined at the respective positions.

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