X-ray source and method for generating X-rays and resurfacing a target material

Abstract

The invention relates to an X-ray source (100) by interaction between a focused laser pulse beam (40) and a target material. According to the invention, the X-ray source (100) comprises a resurfacing device (20), a first laser source (30) capable of emitting said laser pulse beam along a first optical axis, the target material (10) being movable with at least two degrees of freedom, the surface of the target material being adapted to receive the focused laser pulse beam and to generate X-rays, the focused laser pulse beam locally inducing an ablation crater (45) in an area of ​​the surface of the target material, the resurfacing device being configured to resurface the area of ​​the surface of the target material ablated by the laser pulse beam. Figure for the abstract: Fig. 1

Description

Title of the invention: X-ray source and method for generating X-rays and resurfacing a target material technical field

[0001] The present invention relates generally to the field of X-ray sources.

[0002] It relates more particularly to an X-ray source by interaction between a laser beam and a target material.

[0003] X-ray sources are used in particular in medical, industrial or scientific imaging applications. Technological background

[0004] Most X-ray sources include an X-ray tube in which an electrical voltage is applied between two electrodes placed under vacuum.

[0005] More recently, X-ray sources based on the interaction between an intense pulsed laser beam and a target material or metallic conversion material have emerged. A pulsed laser beam focused onto the surface of a metallic material to achieve an intensity greater than approximately 10¹⁵ W.cm⁻² can be used to generate X-rays. Under these conditions, the interaction zone between the laser and the target material becomes a secondary X-ray emitter.

[0006] With each laser pulse, a portion of the solid target is ablated over a surface area on the order of the focal spot. The target is therefore locally destroyed with each laser pulse. A high-average-power, high-peak-power pulsed laser system considered for an X-ray source has a rate, or repetition frequency, on the order of a few hertz (Hz) to a few hundred kHz.

[0007] One solution for renewing the target material in a laser X-ray source consists of moving the target relative to the laser beam so as to move the interaction zone on the target while keeping the X-ray emission zone fixed. Beyond a rate of a few hertz, the displacement of the target is generally continuous with a speed of displacement adapted according to the rate of laser shots so that the impacts of consecutive laser pulses are spatially separated on the target.

[0008] In particular, an X-ray source is known comprising a thick disk of target material. A laser pulse beam is focused onto one face of the disk to generate X-rays reflected from the disk. The displacement of the disk along a The combined motion of rotation around its axis and translation transversely to its axis allows the laser beam's focal point to be moved in a spiral pattern across the surface of the target disk. However, to increase the lifespan of the target disk, it is necessary to increase the disk's diameter, which leads to a significant increase in the weight and size of the X-ray source.

[0009] Another known solution, disclosed by documents FR3088514 and FR1872703, consists of an X-ray source comprising a ribbon of target material wound on one or more reels, as well as means for driving the reels. The reel drive allows the ribbon to be moved transversely to the laser beam. While this solution maximizes the accessible surface area of ​​the stored target material within the limited volume of the laser-to-X-ray conversion system, it has the disadvantage of reduced efficiency at high frequencies. Indeed, in order to maintain a sufficient distance between the impact craters of the laser pulses, increasing the laser rate requires increasing the ribbon's speed, which can then cause it to vibrate and no longer provide the focusing conditions necessary for X-ray generation.A second limitation of ribbon systems is related to the degradation of the mechanical properties of the target material ribbon when a significant fraction of its surface is cratered. Indeed, a heavily cratered ribbon presents an increased risk of tearing or may lose flatness, which impairs its movement or the quality of the laser beam focusing.

[0010] Laser interaction X-ray sources have properties related to the size of the laser focal spot. Furthermore, laser interaction X-ray sources allow the emitted X-ray spectrum to be tuned to the target material. Finally, the impulsive nature of these X-ray sources opens the door to applications in research laboratories, for example, for dynamic studies in materials physics, medical imaging, or non-destructive industrial testing.

[0011] However, currently available laser interaction X-ray sources are not suitable for industrial or medical applications outside of scientific research.

[0012] For such applications, it is desirable to have an X-ray source offering an extended operating time, at least several minutes of continuous emission and at least several tens of hours of emission between manual interventions before replacing the target material, without increasing the size of the source, and adapted to the rates of the laser source.

[0013] It is desirable to propose an industrially manufactured X-ray source that is easy to use and less expensive. Summary of the invention

[0014] In order to remedy the aforementioned drawbacks of the prior art, the present invention proposes an X-ray source by interaction between a focused laser pulse beam and a target material, and comprising a device for resurfacing the target material.

[0015] More particularly, the invention proposes an X-ray source by interaction between a focused laser pulse beam and a target material comprising a resurfacing device, the X-ray source comprising a first laser source capable of emitting said laser pulse beam along a first optical axis, the target material being movable along at least one degree of freedom, the surface of the target material being adapted to receive the focused laser pulse beam and to generate X-rays, the focused laser pulse beam locally inducing an ablation crater in an area of ​​the surface of the target material, the resurfacing device being configured to resurface the area of ​​the surface of the target material ablated by the laser pulse beam.

[0016] Other non-limiting and advantageous features of the X-ray source according to the invention, taken individually or in all technically possible combinations, are as follows:

[0017] - the resurfacing device includes a second laser source configured for emit a focused laser pulse beam along a second optical axis capable of causing localized melting of the target material (10) in the area of ​​the surface of the target material (10) ablated;

[0018] - the resurfacing device includes a mechanical device configured for resurface the area of ​​the target material surface by removing material;

[0019] - the mechanical device includes a turning, grinding and / or polishing;

[0020] - the target material is solid;

[0021] - the target material has the shape of a cylinder, a plate or a disc;

[0022] The invention also proposes a method for generating X-rays by interaction between a first pulsed laser beam and a target material comprising the steps of:

[0023] 1) generation of X-rays by interaction between the pulsed laser beam emitted along a first optical axis and a part of the surface of the target material, locally inducing an ablation crater in an area of ​​the surface of the target material,

[0024] E21) displacement of the target material along at least one translational movement and / or at least a rotational movement, and

[0025] E31) resurfacing of the area of ​​the ablated surface during the generation step X-rays Eli).

[0026] Other non-limiting and advantageous features of the X-ray generation process according to the invention, taken individually or in all technically possible combinations, are as follows:

[0027] - the resurfacing step E31) is carried out mechanically by removing material;

[0028] - the resurfacing step E31) is carried out by melting the area of ​​the ablated surface by means of a second focused laser pulse beam;

[0029] - the X-ray generation steps E1), of target material displacement E21) and E31 resurfacing) are carried out simultaneously;

[0030] - the X-ray generation steps E1) and resurfacing steps E31) are carried out sequentially.

[0031] Of course, the different features, variants and embodiments of the invention can be combined with each other in various ways insofar as they are not incompatible or mutually exclusive.

[0032] The following description with regard to the attached drawings, given by way of non-limiting examples, will make it clear what the invention consists of and how it can be carried out. Brief description of the figures

[0033] In addition, various other features of the invention become apparent from the attached description made with reference to the drawings which illustrate non-limiting embodiments of the invention and where:

[0034] [Fig. 1] schematically represents a laser interaction X-ray source according to a first embodiment,

[0035] [Fig.2] schematically illustrates the relative displacements between a target and a pulsed laser beam in the interaction zone,

[0036] [Fig.3] schematically represents a resurfacing device interacting with the surface of a cylindrical target material according to a first embodiment,

[0037] [Fig.4] schematically represents a resurfacing device interacting with the surface of a cylindrical target material according to a second embodiment.

[0038] [Fig.5] schematically represents an interacting resurfacing device with the surface of a target material in the form of a plate according to the first embodiment.

[0039] [Fig.6] schematically represents an interacting resurfacing device with the surface of a target material in the form of a disc according to the first embodiment.

[0040] It should be noted that in these figures the structural and / or functional elements common to the different variants may have the same references.

[0041] Device

[0042] In this document, for the generation of X-rays, a laser source suitable for generating a pulsed laser beam is considered, having pulse durations between 10 fs and 100 ps, ​​preferably between 20 fs and 10 ps, ​​and even more preferably between 100 fs and 5 ps. The energy per pulse is between 1 mJ and 10 J, and preferably between 20 mJ and 1 J. The laser power is between 1 W and 10 kW, and preferably between 10 W and 5 kW. The laser wavelength is preferably between 0.5 pm and 10 pm. In the remainder of this document, the terms laser beam, laser pulse beam, and pulsed laser beam are used synonymously. The pulsed laser beam is focused to achieve an intensity greater than approximately 1015 W.cm-2 to generate X-rays by interaction between the laser and a target material.For a Gaussian laser beam, the extent of the laser beam's focusing zone transverse to the optical axis of the laser beam is between 1 pm and 50 pm in diameter, for example 5 pm in diameter.

[0043] In figures 1 to 4, identical reference signs designate analogous or similar elements.

[0044] Figure 1 shows an X-ray source 100 comprising a target material 10. The target material 10 is arranged in a housing 90. The target material 10 is held in place by a drive system 15. Simultaneously with the laser pulses, the drive system 15 applies one or more translational and / or rotational movements to the target material 10. The housing 90 is preferably a vacuum chamber. A pumping system allows the housing 90 to be placed under primary or secondary vacuum. The housing 90 preferably has internal or external walls made of a shielding material, for example, lead or tungsten, suitable for absorbing X-rays. The housing 90 has a first opening 61 fitted with a window adapted to receive a first laser pulse beam 40.An optical system 41, for example with a lens, focuses the first laser pulse beam 40 through the window into an interaction zone of the surface of the target material 10.

[0045] The housing 90 has a second opening 92 fitted with another window adapted for the passage of a beam 80 of X-rays emitted by the surface of the target material 10. The second opening 92 has a diameter between 1 mm and 100 mm, preferably between 5 mm and 50 mm. The second opening 92 is transparent to X-rays.

[0046] In the embodiment considered, the target material 10 is solid. By solid, it is understood that the target material 10 has a minimum thickness greater than ten ablation depths (typically 10-100 µm), for example, greater than or equal to 1 mm in diameter and less than or equal to 50 cm in diameter. The target material 10 may contain a central cavity for mounting the drive system 15 within the target material 10 such that the distance between the surface of the target material 10 and the central cavity is greater than or equal to 1 mm. In the embodiment considered, the target material 10 is cylindrical. The cylinder has, for example, a length greater than or equal to 1 cm and less than or equal to 50 cm, for example, 10 cm. The cylinder has, for example, a diameter greater than or equal to 5 cm and a diameter less than or equal to 10 cm, for example, 7 cm.Alternatively, the target material 10 has, for example, the shape of a disc or a rectangular plate.

[0047] The target material 10 may be made of raw metal or metal alloy or deposited on a substrate. The target material 10 is preferably selected from copper, molybdenum, silver, tantalum or tungsten or a metal alloy comprising at least one of these materials.

[0048] The drive system 15 for the target material 10 allows the target material 10 to be moved transversely to the laser beam in at least one direction and / or to be rotated in the direction of at least one axis of rotation. In the embodiment considered, where the target material 10 has a cylindrical shape, the displacement applied by the drive system 15 to the target material 10 is a helical motion. The cylinder of target material 10 moves helically in a direction OZ in an orthonormal coordinate system (OX, OY, OZ). The helical displacement of the target material 10 is intended to allow the abrasion of the largest possible surface area of ​​the target material during a single helical movement.

[0049] Figure 2 illustrates the impact of laser beam pulses on the surface of the target material 10 as a function of the cylinder's displacement. Each laser pulse locally induces an ablation crater 45 in an area of ​​the target material 10's surface. The drive system 15 induces a longitudinal displacement 33 of the target material cylinder 10 along the cylinder's principal axis and a rotational movement 34 of the target material cylinder 10 about the cylinder's principal axis. The helical motion applied by the drive system 15 to the target material cylinder 10 is, for example, constant. By constant helical motion, it is understood that the longitudinal displacement 33 and the rotational movement 34 are applied simultaneously. Alternatively, the longitudinal displacement 33 and the rotational movement 34 are applied sequentially with each revolution of the cylinder. It is understood here that the rotational movement 34 is applied alone until the The perimeter of the target material cylinder 10 is ablated. A translational movement 33 is then applied to the target material cylinder 10 so that a new perimeter of it can be exposed to the first laser beam 40.

[0050] The laser firing rate determines the time between two consecutive pulses. From this, the distance D between two ablation craters 45 in the target material 10 is deduced. The ablation craters 45 all have approximately the same dimensions, and the distance D between ablation craters 45 also remains constant. The precise positioning of the ablation craters 45 on the target material 10 avoids overlapping of the ablation craters 45, which could cause the laser to interact with an area of ​​the surface that has already been ablated. In the embodiment considered, the angle of incidence of the first laser beam 40 on the target material 10 is between 0 degrees and 80 degrees, preferably between 40 and 70 degrees.

[0051] The drive system 15 allows the surface of the target material 10 to be moved at a speed adapted to the laser firing rate to ensure continuous renewal of the target material while utilizing an optimal surface area. Each laser shot ablates a disk- or elliptical-shaped area of ​​the surface, depending on the angle of incidence between the normal to the surface of the target material 10 and the optical axis of the incident laser beam. In the X direction, the focal spot ablates an area of ​​the surface to a depth greater than or equal to 1 pm and less than or equal to 100 pm, for example, 20 pm, and to a diameter greater than or equal to 5 pm and less than or equal to 250 pm, for example, 50 pm. The laser firing rate is generally between 100 Hz and 100 kHz. The speed of the slide is adjusted between approximately 1 mm / s and 10 m / s so that the distance D between two consecutive ablated areas of the surface is greater than 1 Opm.For example, when the target material cylinder 10 has a length of 10 cm, a diameter of 7 cm and the distance between two consecutive ablation craters 45 is 100 pm, 2.2x106 ablation craters can be made, which corresponds to a continuous operating time of 220 s for a laser firing rate of 10 kHz.

[0052] As explained above, once the area of ​​the surface of the target material 10 has been cratered by a laser pulse, it is no longer possible to perform further laser pulses at the same location because the laser focusing conditions are no longer met. The target material is therefore moved by one or more translational movements and one or more rotational movements to present an uncratered area of ​​its surface to the laser beam. Once the entire effective surface of the target material 10 has been ablated, instead of replacing the target material 10 with new target material, a resurfacing device integrated into the X-ray source 100 and configured to resurface the material's surface in situ is proposed here. target 10 and thus allow a new cycle of X-ray generation between the first laser pulse beam 40 and the regenerated surface of the target material 10.

[0053] Figure 3 illustrates a resurfacing device 20 according to a first embodiment comprising a second laser source 50. An optical system 51, for example a lens system, focuses a second laser pulse beam 60 through the viewing window into an interaction zone of the surface of the target material 10 that differs from that of the first laser pulse beam 40. The power of the second laser source is between 1 W and 1000 W, and preferably between 50 W and 500 W. The second laser source has, for example, a wavelength greater than or equal to 200 nm and less than or equal to 2000 nm, and is continuous or pulsed with a frequency, for example, between 1 kHz and 100 kHz. If the second laser pulse beam is pulsed, it has pulses with a duration between 10 fs and 10 ms.

[0054] The interaction of the second laser pulse beam 60 with the surface of the target material 10 causes localized, non-ablation melting of the surface over a height greater than or equal to 5 pm and less than or equal to 100 pm, for example 50 pm, and over a diameter greater than or equal to 100 pm and less than or equal to 10 mm, for example 5 mm. Thus, the surface of the target material is reshaped by the second laser pulse beam 60, resulting in its flattening and the elimination of craters, so that the laser focusing conditions are again met for X-ray generation.

[0055] Advantageously, the diameter and depth of the localized melting zone obtained by the interaction of the second laser pulse beam 60 with the surface of the target material 10 is always greater than the diameter and depth of the ablation crater 45 to obtain a homogeneous result.

[0056] Advantageously, the amount of material removed by this first embodiment is almost zero and thus makes it possible to extend the life of the target material.

[0057] Similar to what occurs during X-ray generation, the drive system 15 for the target material 10 allows the target material 10 to be moved transversely to the laser beam in at least one direction and / or to be rotated about at least one axis of the target material. In the embodiment considered, where the target material 10 has a cylindrical shape, the displacement applied by the drive system 15 to the target material 10 is helical. The cylinder of target material 10 moves helically along an OZ direction in an orthonormal coordinate system (OX, OY, OZ). Preferably, the helical displacement of the target material 10 allows the entire cratered lateral surface of the cylinder of target material 10 to be resurfaced during a single helical movement. Alternatively, resurfacing is achieved by several passes of the resurfacing beam or by sweeps in different directions orthogonal with a scanner, for example. The helical motion applied by the drive system 15 to the target material cylinder 10 is, for example, constant. Alternatively, the longitudinal displacement 33 and the rotational motion 34 are applied sequentially with each revolution of the cylinder.

[0058] Advantageously, the linear or rotary axes of the X-ray source 100 are equipped with position sensors to control the correct positioning of the focal spot of the second laser pulse beam 60 relative to the craters induced by the first laser pulse beam 40. Since the second laser pulse beam 60 is configured to have a focal spot several orders of magnitude larger than the focal spot of the first laser pulse beam 40, it is not necessary to position the focal spot of the second laser pulse beam 60 on the ablation craters 45. The positioning of the focal spot of the second laser pulse beam 60 is such that the areas of the target material 10 where the surface has already been resurfaced are identified.

[0059] In the preferred embodiment of the invention, the entire surface of the target material 10 is resurfaced. Thus, all cratered areas are resurfaced without the need to determine their positions beforehand.

[0060] The second laser pulse beam 60 is configured to have a focal spot whose dimensions are larger than the dimensions of the focal spot of the first laser pulse beam 40, for example, 10 times larger. In the embodiment considered, the diameter of the focal spot of the second laser pulse beam is greater than or equal to 50 pm and less than or equal to 10 mm, for example, 500 µm. Since the diameter D of the ablation craters 45 is of the same order of magnitude or an order of magnitude larger than the diameter of the focal spot of the first laser pulse beam 40, all the ablation craters 45 are resurfaced by the second laser pulse beam during a single movement of the target material 10 created by the displacement system 15.

[0061] According to the preferred embodiment illustrated in [Fig. 3], the X-ray source 100 is configured so that the generation of X-rays by the first pulsed laser beam 40 and the resurfacing of the surface of the target material 10 are performed simultaneously. Simultaneously, it is understood that during the movement of the target material cylinder 10 created by the displacement system 15, the first pulsed laser beam 40 interacts with the surface of the target material cylinder 10 at a first position to generate X-rays, and the second pulsed laser beam 60 resurfaces the surface of the target material cylinder 10 at a second position different from the first. Advantageously, during the same movement of the target material cylinder 10, the surface of the target material is ablated and then resurfaced.

[0062] According to an embodiment not shown, the X-ray source 100 is configured so that the generation of X-rays by the first pulsed laser beam 40 and the resurfacing of the surface of the target material 10 are carried out sequentially. By sequential, it is understood that initially, during a first movement of the target material cylinder 10 created by the displacement system 15, the first pulsed laser beam 40 interacts with the surface of the target material cylinder 10 to generate X-rays. Then, subsequently, during a second displacement movement created by the displacement system 15, the ablated surface is resurfaced by the second pulsed laser beam 60. This second movement can be carried out in the opposite direction to the first displacement movement or in the same direction as the first displacement movement.In this second case, the target material 10 is placed in its initial position prior to the first displacement movement, taking into account the positional shift existing between the focal point of the first laser pulse beam 40 and the second laser pulse beam 60. In this embodiment, the second displacement movement created by the displacement system 15 is, for example, carried out at a speed equal to or different from that of the first displacement movement created by the displacement system 15. In this embodiment, the first laser pulse beam 40 and the second laser pulse beam 60 are, for example, co-propagative.

[0063] Figure 4 illustrates a resurfacing device according to a second embodiment comprising a mechanical device 70 integrated into the X-ray source 100 and configured to resurface the surface of the target material 10 in situ inside the housing 90. The mechanical device 70 comprises, for example, a turning tool, a grinding tool, and / or a polishing tool. In this embodiment, the mechanical device 70 resurfaces the surface of the target material 10 by removing material to a depth, for example, greater than or equal to 5 µm and less than or equal to 100 µm. The lifespan of the target material 10 is therefore shorter than in the previously described embodiment.

[0064] Figure 5 illustrates a resurfacing device 20 according to the first embodiment comprising a target material 10 in the form of a plate.

[0065] Figure 6 illustrates a resurfacing device 20 according to the first embodiment comprising a target material 10 in the form of a disc.

[0066] The X-ray source of this disclosure opens up new applications in medical imaging, for example, mammography. Such an X-ray source also finds applications in non-destructive industrial testing, crystallography, and any other application using X-rays.

[0067] Advantageously, the consumable's lifespan is greatly increased. Indeed, the entire volume of the target material is used instead of just its accessible surface area. The Most applications can benefit from a longer usage time before consumable replacement, which represents a significant economic and operational gain.

[0068] Process

[0069] The invention also relates to methods of generating X-rays by interaction between a first pulsed laser beam and a target material, and of in situ resurfacing of the surface of the target material carried out by a resurfacing device integrated into the X-ray source used for X-ray generation and possibly simultaneously with the X-ray generation. The X-ray source 100 can advantageously be used for the implementation of such methods.

[0070] The invention also relates to a method for generating X-rays by interaction between a first pulsed laser beam and a target material. The method comprises the steps of:

[0071] 1) generation of X-rays by interaction between the pulsed laser beam emitted along a first optical axis and a part of the surface of the target material, locally inducing an ablation crater in an area of ​​the surface of the target material,

[0072] E21) displacement of the target material along at least one translational movement and / or at least a rotational movement, and

[0073] E31) resurfacing of the area of ​​the ablated surface during the generation step X-rays Eli).

[0074] During the X-ray generation step El 1, the first pulsed laser beam 40 emitted along a first optical axis illuminates the surface of the target material 10. The interaction between the first pulsed laser beam 40 and the surface of the target material 10 causes the emission of X-rays by the surface of the target material 10.

[0075] During the displacement step E21, the target material 10 is moved by the displacement system 15 according to at least one translational movement and / or at least one rotational movement.

[0076] During the resurfacing step E31, an area of ​​the surface ablated during the X-ray generation step E1 is resurfaced by the resurfacing device 20. According to a first embodiment of the process, the resurfacing step E31 is carried out by localized melting of the area of ​​the ablated surface of the target material 10 by the second laser pulse beam 60. According to a second embodiment of the process, the resurfacing step E31 is carried out by removing material from the area of ​​the ablated surface of the target material 10 by the mechanical device 70. This material removal is, for example, carried out by turning, grinding and / or polishing.

[0077] The X-ray generation step E1, the displacement step E21, and the resurfacing step E31 are repeated until the effective surface of the target material 10 has been completely cratered, the ablation craters 45 being spaced apart, and then resurfaced for the first time. The target material is then repositioned by the displacement system 15 to its initial position, i.e., the position occupied by the target material 10 at the beginning of the process. The process can then be carried out again, the number of additional times depending on the thickness of the target material 10.

[0078] The X-ray generation step E1 and the displacement step E21 can be repeated several times, for example 1000 times, before proceeding to the resurfacing step E31. Advantageously, this makes it possible to move the focal spot of the first laser pulse beam 40 sufficiently far from the resurfacing device 20 to avoid any interaction between them. The minimum distance is, for example, determined as a function of the diameter of the focal spot of the first laser pulse beam 40, for example greater than or equal to 50 times and less than or equal to 100 times the diameter of the focal spot of the first laser pulse beam 40.

[0079] According to the preferred embodiment of the invention, the X-ray generation step El 1 and the resurfacing step E31 of the surface area of ​​the target material 10 are performed simultaneously. Alternatively, the X-ray generation step El 1 and the resurfacing step E31 of the surface area of ​​the target material 10 are performed sequentially. According to this alternative, initially the X-ray generation step El 1 and the displacement step E21 are repeated until the entire effective surface of the target material 10 is cratered by the first laser pulse beam 60. Subsequently, the displacement system 15 positions the target material such that the first area ablated by the first laser pulse beam 60 is in position to be resurfaced by the resurfacing device 20.Alternatively, the displacement system 15 positions the target material so that the last area ablated by the first laser pulse beam 60 is in position to be resurfaced by the resurfacing device 20. In a third step, the resurfacing E31 and displacement steps are repeated successively until the entire useful surface of the target material 10 is resurfaced.

[0080] According to this variant, since the diameter of the focal spot of the second laser pulse beam 60 can be chosen to be much larger than that of the first laser pulse beam 40, the scanning speed of the second laser pulse beam 60 on the surface of the target material 10 can be chosen to be greater than the scanning speed of the first laser pulse beam 40. Advantageously, the resurfacing step E31 can thus be carried out in less time than the Eli step.

[0081] Of course, various other modifications can be made to the invention in the framework of the attached claims.

[0082]

Claims

Demands

1. X-ray source (100) by interaction between a focused laser pulse beam (40) and a target material (10) comprising a resurfacing device (20), the X-ray source (100) comprising a first laser source (30) capable of emitting said laser pulse beam along a first optical axis, the target material (10) being movable in at least two degrees of freedom, the surface of the target material (10) being adapted to receive the focused laser pulse beam (40) and to generate X-rays, the focused laser pulse beam locally inducing an ablation crater (45) in an area of ​​the surface of the target material, the resurfacing device (20) being configured to resurface the area of ​​the surface of the target material (10) ablated by the laser pulse beam (40).

2. X-ray source (100) according to claim 1, the resurfacing device (20) comprising a second laser source (50) configured to emit a focused, continuous or pulsed laser beam (60) along a second optical axis capable of causing localized melting of the target material (10) in the area of ​​the surface of the target material (10) ablated.

3. X-ray source (100) according to claim 1, the resurfacing device (20) comprising a mechanical device (70) configured to resurface the area of ​​the surface of the target material (10) by material removal.

4. X-ray source (100) according to claim 3, the mechanical device (70) comprising a turning tool, a grinding tool or a polishing tool.

5. X-ray source (100) according to any one of the preceding claims, the target material (10) being solid and having a thickness greater than or equal to 1 mm.

6. X-ray source (100) according to claim 5, the target material (10) having the form of a cylinder, a plate or a disc.

7. A method for generating X-rays by interaction between a first pulsed laser beam and a target material, comprising the steps of: 1) generating X-rays by interaction between the pulsed laser beam emitted along a first optical axis and a portion of the surface of the target material, locally inducing an ablation crater in an area of ​​the surface of the target material, E21) displacement of the target material in at least one translational motion or at least one rotational motion, and E31) resurfacing of the area of ​​the ablated surface during the X-ray generation step Eli) or sequentially.

8. X-ray generation method according to claim 7, the resurfacing step E31) being carried out mechanically by material removal.

9. X-ray generation method according to claim 7, the resurfacing step E31) being carried out by melting the ablated surface area by means of a second focused laser pulse beam.

10. X-ray generation method according to any one of claims 7 to 8, the X-ray generation steps E11), target material displacement E21) and resurfacing E31) being carried out simultaneously.

11. X-ray generation method according to any one of claims 7 to 8, the X-ray generation steps (E1 and resurfacing E31) being carried out sequentially.