JET EJECTION DEVICE

Abstract

The invention provides a microfluidic device (1) for jet ejection, wherein the microfluidic device (1) comprises a hosting chamber (100) defined by a chamber wall (110), wherein the hosting chamber (100) is configured to host a liquid (10), wherein along a device axis of elongation (A.sub.D) the hosting chamber (100) has a chamber length (L.sub.C) defined by a first chamber end (101) and a second chamber end (102), wherein the first chamber end (101) comprises a first chamber opening (1011) for jet ejection from the hosting chamber (100); wherein the chamber wall (110) comprises a pattern (300) of a first surface material (111) and a second surface material (112), wherein the first surface material (111) has an equilibrium contact angle .sub.1>90 for the liquid (10), and wherein the second surface material (112) has an equilibrium contact angle .sub.2 for the liquid (10), wherein .sub.1.sub.220; wherein the pattern (300) comprises a patch (200), wherein the patch has a patch boundary (205), and wherein (a) the patch (200) comprises one of the first surface material (111) and the second surface material (112), and wherein (b) at least 50% of the patch boundary (205) contacts the other of the first surface material (111) and the second surface material (112); wherein the chamber wall (110) has a wall surface area (S.sub.W), wherein the patch (200) has a patch surface area (S.sub.P), wherein 10.sup.4S.sub.P/S.sub.W2*10.sup.1.

Claims

1. A microfluidic device (1) for jet ejection, wherein the microfluidic device (1) comprises a hosting chamber (100) defined by a chamber wall (110), wherein: the hosting chamber (100) is configured to host a liquid (10), wherein along a device axis of elongation (A.sub.D) the hosting chamber (100) has a chamber length (L.sub.C) defined by a first chamber end (101) and a second chamber end (102), wherein the first chamber end (101) comprises a first chamber opening (1011) for jet ejection from the hosting chamber (100); the chamber wall (110) comprises a pattern (300) of a first surface material (111) and a second surface material (112), wherein the first surface material (111) has an equilibrium contact angle .sub.1>90 for the liquid (10), and wherein the second surface material (112) has an equilibrium contact angle .sub.2 for the liquid (10), wherein .sub.1.sub.220; the pattern (300) comprises a patch (200), wherein the patch has a patch boundary (205), and wherein (a) the patch (200) comprises one of the first surface material (111) and the second surface material (112), and wherein (b) at least 50% of the patch boundary (205) contacts the other of the first surface material (111) and the second surface material (112); the chamber wall (110) has a wall surface area (S.sub.W), wherein the patch (200) has a patch surface area (S.sub.P), wherein 10.sup.4S.sub.P/S.sub.W2*10.sup.1; and in a cross-section perpendicular to the device axis of elongation (A.sub.D) the hosting chamber (100) has a perimeter (115) with a chamber perimeter length P.sub.C, wherein the patch (200) covers a patch perimeter length P.sub.P along the perimeter (115), wherein P.sub.P is selected from the range of 0.01*P.sub.C-0.5*P.sub.C.

2. The microfluidic device (1) according to claim 1, wherein the patch (200) has a patch axis of elongation (A.sub.P), wherein the patch (200) has a patch length (L.sub.P) along the patch axis of elongation (A.sub.P) and a patch width (W.sub.P) perpendicular to the patch axis of elongation (A.sub.P), wherein L.sub.P1.5*W.sub.P.

3. The microfluidic device (1) according to claim 2, wherein the patch (200) comprises the first surface material (111), wherein the patch axis of elongation (A.sub.P) makes an angle 80 with the device axis of elongation (A.sub.D), and wherein the patch width W.sub.P is selected from the range of 0.01*L.sub.C-0.2*L.sub.C.

4. The microfluidic device (1) according to claim 2, wherein the patch (200) comprises the second surface material (112), wherein the patch axis of elongation (A.sub.P) makes an angle 30 with the device axis of elongation (A.sub.D), and wherein the patch length (L.sub.P) is selected from the range of 0.2*L.sub.C-0.95*L.sub.C.

5. The microfluidic device (1) according to claim 1, wherein applies that the pattern (300) has a plane of symmetry (150).

6. The microfluidic device (1) according to claim 1, wherein P.sub.P is selected from the range of 0.05*P.sub.C-0.25*P.sub.C.

7. The microfluidic device (1) according to claim 1, wherein the patch contacts the other of the first surface material (111) and the second surface material (112) along 99% of the patch boundary, and wherein the patch (200) has an outline defined by a plurality of line segments, wherein at most two of the line segments are curved.

8. The microfluidic device (1) according to claim 2, wherein the pattern (300) comprises a first set (310) of n patches (200), wherein n2, wherein: the n patches (200) are arranged successively downstream from the second chamber end (102); each patch (200) of the first set (310) comprises the first surface material (111); the patch axis of elongation (A.sub.P) of each patch (200) of the first set (310) makes an angle 80 with the device axis of elongation (A.sub.D).

9. The microfluidic device (1) according to claim 2, wherein the pattern (300) comprises a second set (320) of k patches (200), wherein k2, wherein: each patch (200) of the second set (320) comprises the second surface material (112); each patch (200) of the second set (320) is configured at a distance selected from the range of 0.3*L.sub.C-0.9*L.sub.C from the second chamber end (102); the patch axis of elongation (A.sub.P) of each patch (200) of the second set (320) makes an angle 30 with the device axis of elongation (A.sub.D).

10. The microfluidic device (1) according to claim 9, wherein k=2, and wherein the patches (200) of the second set (320) converge or diverge towards the first chamber end (101).

11. The microfluidic device (1) according to claim 2, wherein the pattern (300) comprises a plurality of third sets (330), wherein: each third set (330) comprises a set of m patches (200), wherein m2, wherein each patch (200) of the third set (330) comprises the second surface material (112), wherein the centroid of the patches (200) lie along an axis (A.sub.M) defined on the chamber wall (110), wherein the axis (A.sub.M) is parallel to the device axis of elongation (A.sub.D), wherein the patch axis of elongation (A.sub.P) of the m patches (200) of the third set (330) makes an angle 550 with the device axis of elongation (A.sub.D), wherein the centroids of two consecutive patches (200) of the third set (330) are configured at a first distance d1, wherein d1 is selected from the range of 0.05*L.sub.C-0.5*L.sub.C.

12. The microfluidic device (1) according to claim 11, wherein the axes (A.sub.M) of two neighboring third sets (330) are arranged at a distance d2, wherein d2 is selected from the range of 0.2*P.sub.C-0.5*P.sub.C.

13. The microfluidic device (1) according to claim 1, wherein the hosting chamber (100) has a chamber height (H.sub.C) selected from the range of 5-400 m, a chamber width (W.sub.C) selected from the range of 2*H.sub.C-10*H.sub.C, and a chamber length (L.sub.C) selected from the range of 100-5000 m, and wherein along at least 80% of the chamber length (L.sub.C) the hosting chamber (100) has a cross-sectional shape approximating a shape selected from the group comprising a rounded rectangle, a stadium, and an oval.

14. A jet ejection system (1000) comprising (i) the microfluidic device (1) according to claim 1, (ii) a liquid supply (500) and (iii) a heating system (600), wherein: the hosting chamber (100) comprises a hosting chamber opening (132); the liquid supply (500) is configured to provide the liquid (10) to the hosting chamber via the hosting chamber opening (132); the heating system (600) is configured to provide radiation (601) to one or more of the chamber wall (110) and the liquid (10) in the hosting chamber (100).

15. A method for ejecting a jet (20) with the microfluidic device (1) according to claim 1, wherein the method comprises: a liquid provision step comprising providing the liquid (10) to the hosting chamber (100), wherein the liquid provision step comprises filling 20-70 vol. % of the hosting chamber (100) with the liquid (10); an ejection step comprising providing radiation (601) to the chamber wall (110) and/or to the liquid (10) such that at least part of the liquid (10) is boiled and a liquid jet (20) is ejected.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0125] Embodiments of the invention will now be described, by way of example only, with reference to the accompanying schematic drawings in which corresponding reference symbols indicate corresponding parts, and in which: FIG. 1A-C schematically depict embodiments of the microfluidic device 1, FIG. 2A schematically depicts patches 200 of different shapes in embodiments, FIG. 2B and FIG. 2C schematically depict the plane of symmetry 150 of the pattern 300 in embodiments, FIG. 3 schematically depicts the pattern 300 comprising a plurality of sets of patches 200 in embodiments, and FIG. 4 schematically depicts an embodiment of a jet ejection system 1000. The schematic drawings are not necessarily on scale.

DETAILED DESCRIPTION OF THE EMBODIMENTS

[0126] FIG. 1A-C schematically depict embodiments of the microfluidic device 1. FIG. 1A shows a cross-section of the microfluidic device 1 in a cross-sectional plane parallel to the device axis of elongation A.sub.D. FIG. 1B depicts an isometric view of a different embodiment of the microfluidic device 1, and FIG. 1C depicts a cross-section of yet another embodiment of the microfluidic device 1 in a cross-sectional plane perpendicular to the device axis of elongation A.sub.D.

[0127] In embodiments, the invention may provide a microfluidic device 1 for jet ejection. In embodiments, the microfluidic device 1 may comprise a hosting chamber 100 defined by a chamber wall 110. Especially, the hosting chamber 100 may be configured to host a liquid 10. In embodiments, along a device axis of elongation A.sub.D the hosting chamber 100 may have a chamber length L.sub.C defined by a first chamber end 101 and a second chamber end 102. Note that, in embodiments, the chamber wall 110 may comprise the first chamber end 101 and the second chamber end 102. Especially, the first chamber end 101 may comprise a first chamber opening 1011 for jet ejection from the hosting chamber 100. In the embodiments depicted i.e., in FIG. 1A-C, the first chamber opening 1011 is as large as the first chamber end 101. However, in other embodiments, the first chamber opening 1011 may (only) be a portion of the of the first chamber end 101.

[0128] Especially, in embodiments, the first chamber end may be (fully) open. In particular, the hosting chamber 100 may have an average area S.sub.H in cross-sections perpendicular to the device axis of elongation A.sub.D, and the first chamber opening may (in a plane perpendicular to the device axis of elongation A.sub.D) have an opening area selected from the range of 0.5*S.sub.H-S.sub.H, especially from the range of 0.9*S.sub.H-S.sub.H, such as (essentially) S.sub.H.

[0129] In embodiments, the chamber wall 110 may comprise a (surface) pattern 300 of a first (repelling) surface material 111 and a second (affinity) surface material 112. Especially, the first surface material 111 may have an equilibrium contact angle .sub.1>90 for the liquid 10, and the second surface material 112 may have an equilibrium contact angle .sub.2 for the liquid 10. More especially, .sub.1.sub.220.

[0130] In embodiments, the (surface) pattern 300 may comprise a (surface) patch 200. In embodiments, the patch 200 may be a two-dimensional shape defined on the surface of the chamber wall 110. In embodiments, the patch may have a patch boundary 205 (see FIG. 2A). Further, in embodiments, the patch 200 may comprise one of the first surface material 111 and the second surface material 112. Further, in embodiments, at least 50% of the patch boundary 205 may contact the other of the first surface material 111 and the second surface material 112. In embodiments, the patch 200 may comprise the first surface material 111 and at least 80% of the patch boundary 205 may contact the second surface material 112. Additionally, in embodiments, the patch 200 may comprise the second surface material 112 and at least 80% of the patch boundary 205 may contact the first surface material 111. In further embodiments, the patch may contact the other of the first surface material 111 and the second surface material 112 along 99% of the patch boundary 205. Generally, the patch 200 may in embodiments be configured away from the first chamber end 101 (such as in the embodiments depicted in FIGS. 1A and 1B). In such embodiments, the patch 200 may be completely surrounded by the other of the first surface material 111 and the second surface material 112. Hence, in such embodiments at least 99% of the patch boundary 205, or (even) 100% of the patch boundary 205 may contact the other of the first surface material 111 and the second surface material 112. However, in other embodiments, the patch 200 may be configured such that patch boundary 205 may be coincident with the first chamber opening 1011. In such embodiments, only a part of the patch 200 may be surrounded by the other of the first surface material 111 and the second surface material 112. Therefore, in such embodiments, at least 50%, such as at least 60%, especially at least 70%, more especially at least 80% of the patch boundary 205 may contact the other of the first surface material 111 and the second surface material 112.

[0131] Note that, in embodiments, the pattern 300 may (also) comprise a plurality of patches 200. Only one patch 200 can be observed in the embodiment shown in FIG. 1A. The embodiments depicted in FIGS. 1B and 1C depict two and four patches 200, respectively.

[0132] In embodiments, the chamber wall 110 may have a (wall) surface area S.sub.W. Especially, the (surface) patch 200 has a (patch) surface area S.sub.P. More especially, 10.sup.4S.sub.P/S.sub.W2*10.sup.1.

[0133] In embodiments, the patch 200 may have a patch axis of elongation A.sub.P. Especially, the patch 200 may have a patch length L.sub.P (see also FIG. 2A) along the patch axis of elongation A.sub.P and a patch width W.sub.P perpendicular to the patch axis of elongation A.sub.P. In embodiments, the patch width W.sub.P may be measured along the chamber wall 110. Especially, L.sub.P1.5*W.sub.P. In the embodiments depicted in FIGS. 1A and 1B, the patch axis of elongation A.sub.P may be perpendicular to the device axis of elongation A.sub.D.

[0134] In embodiments, the patch 200 may have a patch shape approximating a shape selected from the group comprising a triangle, a trapezoid, especially a rectangle, a crescent moon, an oval, a circle, etc. In embodiments, the patch shape may approximate a triangle. In further embodiments, the patch shape may approximate a trapezoid. Yet further, in embodiments, the patch shape may approximate a rectangle. In other embodiments, the patch shape may approximate a crescent. Especially, the patch shape may approximate an oval. More especially, the patch shape may approximate a circle.

[0135] In further embodiments, the patch shape may be similar to the aforementioned shapes, however the curvature of one or more sides of the aforementioned shapes may be different. For example, the patch shape may be triangular-like, wherein the patch shape may be a triangle with one curved side. Hence, in this way, the patch shape may approximate a shape selected from the group comprising a triangle, a trapezoid, especially a rectangle, a crescent moon, an oval, a circle, etc. In embodiments, the patch 200 may have an outline defined by a plurality of line segments, wherein at most two of the line segments are curved. A plurality of different patch shapes in embodiments are depicted in FIG. 2A.

[0136] The term approximate and its conjugations herein, such as in to approximate a shape, refers to being nearly identical to, especially identical to, the following term, for example nearly identical to a circular sector or a semi-cylindrical shape. For example, a patch boundary 205 may define a circular patch 200 but for a defect. Similarly, for example, the rounded shape defined by the patch 200 may not be perfectly round but slightly ellipsoidal. In particular, an object approximating a first shape may herein refer to: a first shape realization encompassing the object, wherein the first shape realization is defined as the smallest encompassing shape of the (2D or 3D, respectively) object wherein the first shape realization has the shape of the first shape, wherein a ratio of the area (volume) of the first shape realization to the area (volume) of the object is 1.2, especially 1.1, such as 1.05, especially 1.02. For instance, a patch 200 may approximate a semi-cylindrical shape, wherein the first shape realization may be defined as the smallest encompassing semi-cylindrical shape of the patch 200, wherein a ratio of the volume of the first shape realization to the volume of the patch 200 is 1.2, especially 1.1, such as 1.05, especially 1.02, including 1. Further, if the dimensions of the first shape are defined, the term approximate may refer to the object and the first shape being superimposable (in 2D or 3D, respectively) such that an intersection between the object and the first shape covers at least n % of the object and at least n % of the shape, wherein n is at least 90%, such as at least 95%, especially at least 98%, such as at least 99%, including 100%.

[0137] In embodiments, the patch 200 may comprise the first surface material 111. Especially, the patch axis of elongation A.sub.P may make an angle 80 with the device axis of elongation A.sub.D. In embodiments, the patch width W.sub.P may be selected from the range of 0.01*L.sub.C-0.2*L.sub.C.

[0138] In embodiments, the patch 200 may comprise the second surface material 112. Especially, the patch axis of elongation A.sub.P may make an angle 30 with the device axis of elongation A.sub.D. In embodiments, the patch length L.sub.P may be selected from the range of 0.2*L.sub.C-0.95*L.sub.C.

[0139] Note that, the angle may especially be the smallest angle between the device axis of elongation (A.sub.D) and the patch axis of elongation (A.sub.P) i.e., no distinction is made between and +, both may be considered .

[0140] In embodiments, it may apply that the pattern 300 (of the first surface material 111 and the second surface material 112) may have a plane of symmetry 150 (see FIG. 2B). Especially, the device axis of elongation A.sub.D may be coincident with the plane of symmetry 150, or alternatively (or additionally) the device axis of elongation A.sub.D may be perpendicular to the plane of symmetry 150. Some embodiments where patterns have a plane of symmetry 150 are depicted in FIGS. 2B and 2C.

[0141] In embodiments, in a cross-section perpendicular to the device axis of elongation A.sub.D the hosting chamber 100 may have a perimeter 115 (or circumference) with a (chamber) perimeter length P.sub.C. Note that the perimeter 115 is indicated in FIG. 1C, wherein the extent of the perimeter 115 of the chamber wall 110 (in a cross-section perpendicular to the device axis of elongation A.sub.D) is, for visualizational purposes, schematically marked by an additional (closed) line (with arrows on either end). This has (also) been indicated in other embodiments in a similar manner in FIG. 2B (I) and FIG. 2C (I). Especially, the patch 200 may cover a (patch) perimeter length P.sub.P along the perimeter 115. In embodiments, P.sub.P may be selected from the range of 0.05*P.sub.C-0.25*P.sub.C.

[0142] In embodiments, in a cross-section perpendicular to the device axis of elongation A.sub.D the hosting chamber 100 has a perimeter 115 (or circumference) with a (chamber) perimeter length P.sub.C. Especially, the patch 200 may cover a (patch) perimeter length P.sub.P along the perimeter 115. More especially, P.sub.P may be selected from the range of 0.4*P.sub.C-P.sub.C.

[0143] In embodiments, the pattern 300 may comprise a plurality of patches 200. Especially, the pattern 300 may comprise a plurality of sets of patches 200. FIG. 3 depicts such embodiments.

[0144] In embodiments, the hosting chamber 100 may have a chamber height H.sub.C selected from the range of 5-400 m, a chamber width W.sub.C selected from the range of 2*H.sub.C-10*H.sub.C, and a chamber length L.sub.C selected from the range of 100-5000 m. Further, in embodiments, along at least 80% of the chamber length L.sub.C the hosting chamber 100 may have a cross-sectional shape approximating a shape selected from the group comprising a rounded rectangle, a stadium, and an oval.

[0145] FIG. 2A schematically depicts patches 200 of different shapes in embodiments.

[0146] In embodiments, the patch 200 may be defined by a plurality of sides. Embodiment I depicts a rectangular patch 200 defined by a longer length L.sub.P as compared to the width W.sub.P. In embodiments, the patch axis of elongation A.sub.P may pass through the midpoints of at least one side of the patch 200.

[0147] Furthermore, in embodiments, two sides of the patch 200 may be configured parallel to the patch axis of elongation A.sub.P. Note that the orientation of the patch 200 may influence the heterogenous surface chemistry of the chamber wall 110. Especially, the patch 200 may be configured at an angle with the device angle of elongation A.sub.D. Embodiment II is similar to embodiment I, however the patch 200 in embodiment II is oriented in a perpendicular direction to embodiment I.

[0148] In embodiment III of FIG. 2A, the patch 200 comprises a crescent shaped patch 200. Here, the patch 200 may especially be defined by just two curves of different radii forming a crescent shape. Note that in such embodiments, (alternative to a patch axis of elongation A.sub.P) a patch axis of orientation A.sub.O may be defined especially passing through the midpoint of the two curves (indicated by the dashed line).

[0149] In embodiment IV of FIG. 2A, the patch 200 comprises a half-stadium shape. A half-stadium shape may be defined by two parallel and equal sides and two connecting lines that connect the ends of the parallel sides to form a close two-dimensional region, wherein one of the two connecting sides is a straight line and the other is a curved line. In this embodiment, the patch length L.sub.P of the patch 200 may be measured along the direction of the parallel sides and the patch width W.sub.P may be measured as the distance between the two parallel sides (as indicated in the figure).

[0150] The patch axis of elongation A.sub.P of a (2D) shape may herein especially refer to an axis oriented along the direction of elongation and passing through the fictional center of mass of the (2D) shape (would the (2D) shape have an arbitrary thickness). In embodiments, the axis of elongation A.sub.P may pass through the midpoints of the shortest sides of the smallest rectangle realization encompassing the shape.

[0151] In embodiment V of FIG. 2A, the patch 200 comprises a patch 200 comprising three sides. In such an embodiment, the patch axis of elongation A.sub.P may be defined passing through the midpoint of one of the sides and through the point of intersection of the other two sides. In embodiments, wherein the patch 200 may comprise an odd number of sides, the patch axis of elongation A.sub.P may be defined through the midpoint of one of the sides and through the intersection of two other sides opposite to said side (such as depicted in embodiment VI).

[0152] Note that in embodiments, the patch 200 may (also) have other patch shapes approximating a shape selected from the group comprising a triangle, a trapezoid, especially a rectangle, a crescent moon, an oval, a circle, etc. Furthermore, in embodiments, the patch 200 may have a wave-like shape, wherein the patch length L.sub.P in such an embodiment may be measured in a direction along the same direction in which the wavelength may be measured and the patch width W.sub.P may be measured as the distance between the crest and the trough of the wave-like shape. In further embodiments, the patch 200 may have an outline defined by a plurality of line segments. Especially, at most two of the line segments may be curved.

[0153] FIG. 2B and FIG. 2C schematically depict embodiments illustrating the plane of symmetry 150 of the pattern 300. In embodiments, in a cross-section perpendicular to the device axis of elongation A.sub.D the hosting chamber 100 may have a perimeter 115 (or circumference) with a (chamber) perimeter length P.sub.C. Especially, the patch 200 may cover a (patch) perimeter length P.sub.P along the perimeter 115. In embodiments, P.sub.P may be selected from the range of 0.05*P.sub.C-0.25*P.sub.C. In further embodiments, P.sub.P may be selected from the range of 0.4*P.sub.C-P.sub.C.

[0154] FIG. 2B depicts a cross-section perpendicular to the device axis of elongation A.sub.D of embodiments comprising a hosting chamber 100 with a circular (or rounded) cross-section. Embodiment I comprises a pattern 300 comprising (only) one patch 200. In the depicted embodiment, the pattern 300 may have one plane of symmetry 150. Likewise, in embodiment II, the pattern 300 comprises two patches 200. In the depicted embodiment, the pattern 300 may have two planes of symmetry 150. The planes of symmetry 150 are indicated by dashed lines. In the depicted embodiments, the pattern 300 may have a further plane of symmetry 150, such as the cross-sectional plane.

[0155] FIG. 2C depicts a cross-section perpendicular to the device axis of elongation A.sub.D of embodiments comprising a hosting chamber 100 with an oval cross-section. Here, the chamber wall 110 in embodiment I, II, III and IV comprises one, two, three and four patches 200, respectively. Analogous to the embodiments in FIG. 2B, the pattern 300 may in embodiments comprise at least one plane of symmetry 150. For instance, the pattern 300 in embodiments I and III comprise (at least) one plane of symmetry 150. The pattern 300 in embodiments II and IV have (at least) two planes of symmetry.

[0156] FIG. 3 schematically depicts embodiments wherein the pattern 300 comprises a plurality of sets of patches 200.

[0157] In embodiment I, the pattern 300 comprises a first set 310 of n patches 200. Especially, n may at least be two. In embodiment I n is three. In embodiments, the n patches 200 may be arranged successively (and especially equidistantly) (in a direction parallel to the device axis of elongation A.sub.D) downstream from the second chamber end 102. Further, in embodiments, each patch 200 of the first set 310 may comprise the first surface material 111. Yet further, in embodiments, the patch axis of elongation A.sub.P of each patch 200 of the first set 310 may make an angle 80 with the device axis of elongation A.sub.D. In the embodiment depicted, the liquid is filled up to the first patch 200 of the first set 310 of n patches 200.

[0158] In embodiment II, the pattern 300 comprises a second set 320 of k patches 200. Especially, k may at least be two. In embodiment II, k is three. Note that, in embodiments, the pattern 300 may have a plurality of sets of patches 200. For instance, in the embodiment depicted, the pattern 300 comprises a first set 310 of one patch 200 and the second set 320 of three patches 200.

[0159] Further, in embodiments, each patch 200 of the second set 320 may comprise the second surface material 112. Especially, each patch 200 of the second set 320 may be configured at a (shortest) distance selected from the range of 0.3*L.sub.C-0.9*L.sub.C from the second chamber end 102 (measured along the device axis of elongation A.sub.D). In embodiments, the patch axis of elongation A.sub.P of each patch 200 of the second set 320 may make an angle 30 with the device axis of elongation A.sub.D. Additionally or alternatively, in embodiments, the patches 200 of the second set 320 may converge or diverge towards the first chamber end 101.

[0160] As mentioned before, the pattern 300 may comprise a plurality of sets, wherein each set may comprise a plurality of patches 200. Embodiment III depicts a microfluidic device comprising a plurality of third sets 330.

[0161] In embodiments, each third set 330 may comprise a set of m patches 200. In embodiments, m may at least be two. Embodiment III comprises two third sets 330 of m patches 200, wherein each third set 330 comprises three patches 200.

[0162] In embodiments, each patch 200 of the third set 330 may comprise the second surface material 112. Especially, the centroid of (all) the patches 200 may lie along an axis A.sub.M defined on the chamber wall 110. More especially, the axis A.sub.M may be parallel to the device axis of elongation A.sub.D. In embodiments, the patch axis of elongation A.sub.P of the m patches 200 of the third set 330 may make an angle 550 with the device axis of elongation A.sub.D. Further, in embodiments, the centroids of two consecutive patches 200 of the third set 330 may be configured at a first distance d1. Especially, d1 may be selected from the range of 0.05*L.sub.C-0.5*L.sub.C.

[0163] Furthermore, in embodiments, the axes A.sub.M of two neighboring third sets 330 may be arranged at a distance d2. Especially, d2 (measured in a perpendicular direction to the axis A.sub.M and along the chamber wall 110) may be selected from the range of 0.2*P.sub.C-0.5*P.sub.C. In the embodiment depicted in FIG. 3 (III), the first third set 330 makes a positive angle and the second third set 330 makes a negative angle . Hence, in this way, (patches 200 of) the plurality of third sets 330 may converge (or diverge) towards the first chamber end 101. In particular, in the embodiment depicted in FIG. 3 (III), the patches 200 of the plurality of third sets 330 may converge towards the first chamber end 101, especially the patches 200 of different third sets 330 may converge towards the first chamber end 101.

[0164] FIG. 4 schematically depicts an embodiment of a jet ejection system 1000.

[0165] In a further aspect, the invention may provide a jet ejection system 1000 comprising (i) the microfluidic device 1, (ii) a liquid supply 500 and (iii) a (laser-based) heating system 600. Note that the heating system 600 may in embodiments facilitate providing energy to the liquid 10 hosted in the hosting chamber 100. It will be apparent to the skilled person that other sources of energy may in embodiments (also) be used to provide energy to the liquid 10, for example by means of a piston, Joule heating, dielectric breakdown, etc. Some of these embodiments have been discussed further above.

[0166] In embodiments, the hosting chamber 100 may comprise a hosting chamber opening 132. Further, in embodiments, the liquid supply 500 (comprising stored liquid 550) may be configured to provide the liquid 10 to the hosting chamber 100 via the hosting chamber opening 132. Especially, tubes or (micro) pipes 510 may be used to connect the liquid supply 500 to the hosting chamber opening 132. Furthermore, the (laser-based) heating system 600 may be configured to provide (laser) radiation 601 to one or more of the chamber wall 110 and the liquid 10 in the hosting chamber 100. Especially, in embodiments, the laser radiation 601 may comprise an infrared laser pulse 610.

[0167] In embodiments, the hosting chamber opening 132 may be located at a distance L.sub.O from the second chamber end 102. In embodiments, L.sub.O may be selected from the range of 10-2000 m. Note that in some embodiments, the hosting chamber opening 132 may (also) be configured in the second chamber end 102, i.e. L.sub.O=0. Further, in embodiments, the hosting chamber opening 132 may have a diameter D.sub.O. Especially, D.sub.O may be selected from the range of 1-1000 m.

[0168] In the embodiment depicted in FIG. 4, the (laser-based) heating system 600 may (be configured to) shine a beam of laser radiation 601 onto the liquid 10 via the chamber wall 110. The energy provided by the laser radiation 601 may especially be absorbed by the liquid 10 in the hosting chamber 100.

[0169] Further, in embodiments, the liquid 10 may in embodiments be filled to a predetermined volume (via the hosting chamber opening 132), wherein the advancement of the liquid meniscus may be arrested by means of the patch 200.

[0170] The heat provided by the laser radiation 601 may vaporize at least a part of the liquid 10. The expansion of the vaporized liquid 10 may accelerate the liquid 10 along the device axis of elongation A.sub.D. Thus, the microfluidic jet 20 may be ejected from the microfluidic device 1.

[0171] In a further aspect, the invention provides a method for ejecting a jet 20 with the microfluidic device 1. In embodiments, the method may comprise a liquid provision step and an ejection step. In embodiments, the liquid provision step may comprise providing the liquid 10 to the hosting chamber 100. Especially, the liquid provision step may comprise filling 20-70 vol. % of the hosting chamber 100 with the liquid 10.

[0172] In embodiments, the ejection step may comprise providing radiation 601 to the chamber wall 110 and/or to the liquid 10 such that at least part of the liquid 10 is boiled (or vaporized) and a liquid jet 20 is ejected. Further, in embodiments, the ejection step may comprise vaporizing part of the liquid 10 (in the hosting chamber 100) by heating the liquid 10. Especially, heat may be provided at a power selected from the range of 0.1-10 W.

[0173] The term plurality refers to two or more. Furthermore, the terms a plurality of and a number of may be used interchangeably. The terms substantially or essentially herein, and similar terms, will be understood by the person skilled in the art. The terms substantially or essentially may also include embodiments with entirely, completely, all, etc. Hence, in embodiments the adjective substantially or essentially may also be removed. Where applicable, the term substantially or the term essentially may also relate to 90% or higher, such as 95% or higher, especially 99% or higher, even more especially 99.5% or higher, including 100%. Moreover, the terms about and approximately may also relate to 90% or higher, such as 95% or higher, especially 99% or higher, even more especially 99.5% or higher, including 100%. For numerical values it is to be understood that the terms substantially, essentially, about, and approximately may also relate to the range of 90%-110%, such as 95%-105%, especially 99%-101% of the values(s) it refers to.

[0174] The term comprise also includes embodiments wherein the term comprises means consists of. The term and/or especially relates to one or more of the items mentioned before and after and/or. For instance, a phrase item 1 and/or item 2 and similar phrases may relate to one or more of item 1 and item 2. The term comprising may in an embodiment refer to consisting of but may in another embodiment also refer to containing at least the defined species and optionally one or more other species.

[0175] Furthermore, the terms first, second, third and the like in the description and in the claims, are used for distinguishing between similar elements and not necessarily for describing a sequential or chronological order. It is to be understood that the terms so used are interchangeable under appropriate circumstances and that the embodiments of the invention described herein are capable of operation in other sequences than described or illustrated herein.

[0176] The devices, apparatus, or systems may herein amongst others be described during operation. As will be clear to the person skilled in the art, the invention is not limited to methods of operation, or devices, apparatus, or systems in operation.

[0177] The term further embodiment and similar terms may refer to an embodiment comprising the features of the previously discussed embodiment, but may also refer to an alternative embodiment.

[0178] It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and that those skilled in the art will be able to design many alternative embodiments without departing from the scope of the appended claims.

[0179] In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim.

[0180] Use of the verb to comprise and its conjugations does not exclude the presence of elements or steps other than those stated in a claim. Unless the context clearly requires otherwise, throughout the description and the claims, the words comprise, comprising, include, including, contain, containing and the like are to be construed in an inclusive sense as opposed to an exclusive or exhaustive sense; that is to say, in the sense of including, but not limited to.

[0181] The article a or an preceding an element does not exclude the presence of a plurality of such elements.

[0182] The invention may be implemented by means of hardware comprising several distinct elements, and by means of a suitably programmed computer. In a device claim, or an apparatus claim, or a system claim, enumerating several means, several of these means may be embodied by one and the same item of hardware. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.

[0183] The invention also provides a control system that may control the device, apparatus, or system, or that may execute the herein described method or process. Yet further, the invention also provides a computer program product, when running on a computer which is functionally coupled to or comprised by the device, apparatus, or system, controls one or more controllable elements of such device, apparatus, or system.

[0184] The invention further applies to a device, apparatus, or system comprising one or more of the characterizing features described in the description and/or shown in the attached drawings. The invention further pertains to a method or process comprising one or more of the characterizing features described in the description and/or shown in the attached drawings. Moreover, if a method or an embodiment of the method is described being executed in a device, apparatus, or system, it will be understood that the device, apparatus, or system is suitable for or configured for (executing) the method or the embodiment of the method, respectively.

[0185] The various aspects discussed in this patent can be combined in order to provide additional advantages. Further, the person skilled in the art will understand that embodiments can be combined, and that also more than two embodiments can be combined. Furthermore, some of the features can form the basis for one or more divisional applications.