Fiber-coupled optics for beam shaping, optical system and adapter

Abstract

Fiber-coupled optics for generating a non-Gaussian intensity profile with an optical fiber (10) having an end facet (18), a beam shaping optic (12) which is arranged on the end facet (18), wherein the beam shaping optic (12) is designed as a micro-optics, characterized in that the micro-optics (12) is arranged in an adapter (50), wherein the fiber (10) has a fiber connector and the adapter (50) has a receptacle for receiving the fiber connector (54), wherein the adapter further has a recess, wherein the micro-optics (12) is arranged in the recess of the adapter.

Description

The present invention relates to a fiber-coupled optic for generating a non-Gaussian intensity profile. Furthermore, the present invention relates to an optical system for generating a non-Gaussian intensity profile using such a fiber-coupled optic. The present invention also relates to an adapter for connecting a fiber optic connector to a corresponding optic. Many optical applications require specific light intensity distributions. This applies particularly to applications in metrology, materials processing, imaging, and sensor technology, especially those involving non-Gaussian laser light distributions. To provide such a non-Gaussian intensity profile, suitable beam-shaping optics are known to be used. These are typically integrated into a free beam. The beam-shaping optics are, for example, specially shaped lenses or other optical devices. A particular difficulty with conventional implementations is that, in the case of a collimated beam, two freeform surfaces are usually required. In simplified terms, the first freeform surface redistributes the intensity profile of the incident beam, and the second freeform surface corrects and flattens the wavefront of the redistributed beam. This requires two freeform surfaces with tight manufacturing tolerances, which are difficult to produce and therefore expensive. In this case, deviations in the shape of the freeform surfaces directly lead to non-collimated beam-shaping conditions.Furthermore, the mechanical handling of perfectly manufactured freeform surfaces is also difficult. In particular, the freeform surfaces must be aligned with high precision. This requires the adjustment of three spatial and three rotational degrees of freedom within the alignment process. This is especially challenging and requires specialized mechanical handling or fixtures, which further increases the complexity and thus the cost of these systems. US 2017 / 0017035 A1 describes a process in which the end facet of a fiber is modified by means of a stamping process in such a way that a non-Gaussian beam profile is created. DE 10 2014 208 756 A1 describes a method for injection molding an optical element onto an end facet of a fiber. EP 1 635 204 A1 describes a method in which a diffractive / refractive element is introduced into the end facet of a fiber by means of a stamping process or is glued onto a wafer. GISSIBL, Timo et al., “Sub-micrometre accurate free-form optics by three-dimensional printing on single-mode fibres”, Nature communications, Vol. 7, 2016, Article no. 11763, 9 pp., ISSN 2041-1723 describes a fiber-coupled optic for generating a non-Gaussian intensity profile, which is arranged at an end facet of the optical fiber. The object of the present invention is to create a simplified and cost-effective optical setup for generating a non-Gaussian intensity profile. The problem is solved by a fiber-coupled optic according to claim 1, an optical system according to claim 14, and an adapter according to claim 18. The fiber-coupled optic for generating a non-Gaussian intensity profile or a non-Gaussian intensity distribution according to the present invention comprises an optical fiber with an end facet. Furthermore, the fiber-coupled optic comprises beam shaping optics arranged at the end facet. The beam shaping optics are designed as micro-optics. Since the beam shaping optics are designed as micro-optics, they can be directly combined with the end facet of the optical fiber, thus providing an integrated fiber-coupled optic. The beam shaping optics are configured to generate a non-Gaussian intensity profile from the light supplied by the optical fiber.In most optical setups, the light from laser sources is supplied via an optical fiber, fiber optic cable, waveguide, or similar medium. Prior art requires an additional component for collimating the light from the optical fiber, so that collimated laser light is supplied to the respective optical setup to generate the non-Gaussian intensity profile. Thus, prior art methods require a multitude of individual components for collimation and beam shaping, further increasing the system's size and cost. According to the present invention, the beam shaping optics used, which are arranged at the end facet of the optical fiber, shape the divergent light from the optical fiber and generate a non-Gaussian intensity profile. This simplifies the setup by reducing the number of required components.At the same time, the beam shaping optics, which are designed as micro-optics, can be manufactured cost-effectively. According to the invention, the micro-optics are arranged in an adapter, wherein the fiber has a fiber connector and the adapter has a receptacle for receiving the fiber connector. The adapter further has a recess in which the beam-shaping optics are arranged. Thus, the beam-shaping optics can be easily connected to an optical fiber that already has a fiber connector by means of the adapter. The adapter allows the beam-shaping optics to be connected to the end facet of the fiber in a unique orientation. In particular, the receptacle of the adapter is designed to positively engage the fiber connector, thereby defining a unique position of the fiber connector in the receptacle. Due to the design of the fiber connector and the adapter, no further adjustment is necessary.In particular, the fiber connector receptacle is axially aligned with the recess which has the beam shaping optics, so that the receptacle and the recess have a common optical axis. Preferably, the non-Gaussian intensity profile has a top-hat profile, a donut profile, a rectangular profile, a square profile, or a multi-spot profile. Alternatively, a logo can be generated as the starting profile using beam shaping optics, which can then be displayed. Preferably, the micro-optics have a diameter in the range of 50 µm to 1500 µm, preferably 200 µm to 500 µm. Due to the small dimensions of the micro-optics, integration with the optical fiber is possible. The optical system of the fiber-coupled optics can therefore be designed compactly. Preferably, the micro-optics have a diameter that is essentially the same as the diameter of the optical fiber. This allows for the creation of an integrated system of micro-optics and optical fiber. Alternatively, the micro-optics have a diameter smaller than the diameter of the fiber, so that the light exiting the core of the optical fiber can be suitably shaped by the micro-optics. Known fibers typically have a cladding diameter of 250 µm or less, and in particular 125 µm, and a core diameter of less than 50 µm, and in particular less than 15 µm. Preferably, the micro-optics are fabricated using 3D laser writing, and in particular using two-photon laser writing. It has been shown that suitable structures can be created on a corresponding scale using 3D laser writing with the accuracy required to achieve a reliable non-Gaussian intensity distribution. In 3D laser writing, a photoresist is locally cured using a focused laser beam to create the desired structure. This allows for the precise fabrication of small structures and the desired miniaturization of the micro-optics. Simultaneously, the 3D laser writing process achieves high reproducibility, enabling the reliable fabrication of micro-optics with the desired optical properties. At the same time, the cost of such micro-optics is low. Preferably, the micro-optics are monolithic. The monolithic design of the micro-optics allows for a particularly compact design. In particular, the alignment of the individual components of the beam-shaping optics relative to each other is fixed due to the monolithic design. Thus, according to the present invention, alignment of the individual elements of the beam-shaping optics, as required, for example, in the prior art, is no longer necessary. Preferably, the micro-optics are made of a transparent polymer. The transparent material is, in particular, an acrylate or an epoxy. Here, "transparent" refers to the material's property of substantially transmitting light in the near-UV, visible wavelength range, and / or near-infrared. "Substantially" means that more than 50% of the light passes through the material, preferably more than 70%, more preferably more than 90%, and most preferably more than 95%. Preferably, the micro-optics are produced directly on the end facet of the optical fiber and thus directly and immediately connected to it. This can be achieved in particular by using a 3D laser printer to produce the micro-optics on the end facet of the optical fiber. This ensures that the micro-optics are firmly and permanently connected to the end facet of the optical fiber. Simultaneously, the orientation of the micro-optics relative to the optical fiber can be fixed and is immutable due to the connection between the micro-optics and the end facet of the optical fiber. Subsequent realignment of the micro-optics relative to the end facet of the optical fiber is therefore no longer necessary. Alternatively, the micro-optics can be directly attached or glued onto the end facet for connection to the optical fiber. Preferably, the micro-optics are at least partially enclosed by a sleeve. This increases the mechanical stability of the micro-optics and protects them against external influences or damage. Specifically, the micro-optics are completely enclosed by a sleeve, although, of course, the light-entry and light-emission surfaces of the micro-optics remain uncovered, allowing light to pass through. In particular, a fiber end, which has the end facet of the optical fiber, is also at least partially enclosed by the sleeve. This further increases the mechanical stability of the micro-optics and protects the connection between the micro-optics and the optical fiber from external mechanical influences. The sleeve thus simultaneously encloses at least part of the micro-optics and one end of the optical fiber. Preferably, the micro-optics are cylindrical in shape. In particular, if a sleeve is provided for the mechanical protection of the micro-optics, this sleeve is also cylindrical in shape. Preferably, the micro-optics has an entry surface which is arranged in the direction of the end facet, and an exit surface which is arranged opposite the entry surface, so that light from the fiber enters the micro-optics through the entry surface and exits the micro-optics via the exit surface or vice versa. Preferably, the exit surface is designed as a freeform surface and / or a diffractive surface. The freeform surface and / or the diffractive surface allows for adjustment of the intensity distribution or intensity profile. Here, the freeform surface acts as a refractive element, whereas the diffractive surface adjusts the intensity profile through diffraction. Preferably, the exit surface is designed as a flat surface. This allows the exit surface to be cleaned in the usual way, while simultaneously protecting the surfaces of the beam shaping optics, which lead to the non-Gaussian intensity distribution, from external influences. Preferably, the micro-optics have a cavity. This cavity is free of the transparent material that forms the micro-optics and can, for example, be filled with air or a gas. Preferably, the cavity has at least one internal surface configured as a diffractive or freeform surface for adjusting the intensity profile by refraction or diffraction. This internal surface can be arranged substantially perpendicular to the optical axis or substantially parallel to the exit surface and / or entrance surface and / or the end facet of the optical fiber. In particular, the at least one internal surface can define the cavity in the direction of the entrance surface or in the direction of the exit surface. More specifically, the cavity has two internal surfaces, wherein a first internal surface defines the cavity in the direction of the entrance surface and a second internal surface defines the cavity in the direction of the exit surface, and wherein both the first and second internal surfaces are configured as diffractive (especially freeform) and / or refractive surfaces.The first inner surface and the second inner surface can be identical or different. Preferably, the cavity of the micro-optics is open towards the end facet. Thus, the cavity connects directly to the end facet of the optical fiber. In particular, the cavity at the location of the end facet, or the entry surface of the micro-optics, has a diameter equal to or greater than the core of the optical fiber. Therefore, the micro-optics contains no material at the location of the end facet of the optical fiber. This is typically also the location of highest intensity. Especially during the transmission of high-power laser light, damage to the micro-optics can occur due to the high intensity at the transition from the core of the optical fiber to the micro-optics. However, since the micro-optics has a cavity precisely at the location of the core of the optical fiber, such damage can be avoided.The light beam of the optical fiber, which emerges from the core, spreads out more quickly, so that when it enters the material of the micro-optics, spaced away from the end facet, the intensity has already dropped, thus preventing damage to the micro-optics. Preferably, the micro-optics has exactly one freeform surface and / or diffractive surface for generating the non-Gaussian intensity profile. The present invention further relates to an optical system for generating a non-Gaussian intensity distribution with a fiber-coupled optic as described above. The optical system further comprises a focusing optic with at least one lens. By combining the fiber-coupled optic, which is arranged directly at the end facet of the optical fiber, and the focusing optic, a collimated light beam can be generated which exhibits a non-Gaussian intensity distribution. Preferably, the at least one lens has a diameter in the range of 10 mm to 50 mm, more preferably in the range of 20 mm to 30 mm. Thus, the at least one lens is a macroscopic lens, which is specifically not designed as a micro-optic. This ensures sufficiently large diameters of the light spot to be achieved. Preferably, the distance between the fiber-coupled optics and the focusing optics is between 50 mm and 200 mm. In particular, the distance between the fiber-coupled optics and the focusing optics corresponds essentially to the focal length of the focusing optics. In this case, divergent light exiting the fiber-coupled optics at the exit surface is collimated by the focusing optics. Preferably, the focusing optics include a zoom lens. In particular, the focusing optics include at least two lenses, which are designed, for example, as a diverging lens and a converging lens. The distance between the two lenses thus allows for simple dynamic adjustment of the beam diameter. The present invention further relates to an adapter for connection to a fiber optic connector, wherein the adapter has an adapter element with a receptacle for receiving a fiber optic connector and, in particular, a ferrule of a fiber optic connector, for example, an FC connector, an F-SMA connector, an SC connector, or the like. Furthermore, the adapter has a recess in which a beam-shaping optic is arranged, wherein the beam-shaping optic is designed as a micro-optic. In particular, the beam-shaping optic is designed as described above. The invention will now be explained in more detail with reference to preferred embodiments and the accompanying figures. Figure 1 shows an embodiment from the prior art, Figures 2A-2F show embodiments of an optical system according to the present invention, Figures 3A-3D show embodiments of a fiber-coupled optic according to the present invention, Figures 4A and 4B show a further embodiment of an optical system according to the present invention, Figure 5 shows a further embodiment of an optical system which is not part of the present invention, Figure 6 shows a further embodiment of an optical system which is not part of the present invention, Figures 7A and 7b show an embodiment of an adapter according to the present invention, and Figures 8A and 8B show a further embodiment of an optical system according to the present invention. Fig. 1 shows the prior art. Light transported via an optical waveguide or optical fiber 10' emerges divergently at the end facet of the optical fiber 10' and is collimated by a focusing lens 14'. This results in a Gaussian intensity distribution 16', which is also shown in Fig. 1. The lens 14' is, for example, a macroscopic lens with a diameter of 1 inch or 2 inches, which is arranged at a suitable distance from the end facet of the optical fiber 10'. The alignment of the lens 14' relative to the optical fiber 10' in all three spatial directions, as well as any tilts relative to the end facet of the optical fiber 10', must be adjusted to obtain an optimally collimated output beam. Furthermore, the Gaussian intensity distribution in the area 17 is visible in Fig. 1. In the following figures, identical or similar components are marked with the same reference symbols. Reference is made below to Figures 2A to 2F. According to the present invention, a beam-shaping optic 12, designed as a micro-optic, is arranged at an end facet of a fiber 10. The beam-shaping optic 12 has a diffractive or refractive element by means of which the intensity distribution of the light exiting the optical fiber 10 can be adjusted. Furthermore, the light is divergent and is collimated by means of a focusing optic 14. In Figure 2A, collimated light with a top-hat intensity distribution 16 is achieved. The intensity distribution is also shown in a grayscale in Figure 2A. This essentially corresponds to the generated spot or light distribution when the light is directed onto a screen after the focusing optic 14. The uniform distribution of intensity over the area 17 is evident from Figure 2A.Furthermore, the beam shaping optics 12 generate a circular intensity distribution. In Fig. 2B, the design of the beam shaping optics 12 results in a donut-shaped intensity profile 16 with collimated light. The circular intensity distribution generated in the area 17 is also shown in Fig. 2B. In Fig. 2C, a top-hat intensity profile is generated again, corresponding to Fig. 2A, whereby in the embodiment of Fig. 2C, the intensity distribution in the area 17 is square. In Fig. 2D, a top-hat intensity profile is again generated, corresponding to Fig. 2A, whereby in the embodiment of Fig. 2D, the intensity distribution in the area 17 is circular and also generates a logo (here the letter "F"). In Fig. 2E, the beam shaping optics 12 are configured analogously to the beam shaping optics of Fig. 2A, wherein the focusing optics 14 are configured as a diverging lens, thus achieving a diverging light beam with a top-hat intensity distribution 16. In Fig. 2F, a focused output beam with a top-hat intensity profile 16 is achieved. Here, the beam shaping optics 12 are configured identically or similarly to the beam shaping optics of Figs. 2A and 2E to achieve a top-hat intensity distribution. The focusing optics 14 are configured as a converging lens. Reference is made below to Figures 3A to 3D, which show fiber-coupled optics according to the present invention. A beam-shaping optic 12 is arranged on an end facet 18 of an optical fiber 10. The beam-shaping optic 12 has a light-entry surface 20 and a light-emission surface 22. The beam-shaping optic 12 can be produced directly on the end facet 18 of the optical fiber 10, for example, by means of 3D laser writing or two-photon laser writing. It has been shown that suitable structures can be created on a corresponding scale using 3D laser writing with the accuracy required to achieve a reliable non-Gaussian intensity distribution. In 3D laser writing, a photoresist is locally cured by means of a focused laser beam to create the desired structure.This allows for the precise creation of small structures and the desired miniaturization of micro-optics. Simultaneously, the 3D laser writing process achieves high reproducibility, enabling the reliable production of micro-optics with the desired optical properties. At the same time, the cost of such micro-optics is low. The micro-optics can be monolithic. This monolithic design allows for a particularly compact form. In particular, the alignment of the individual components of the beam-shaping optics relative to each other is fixed due to the monolithic construction. Thus, according to the present invention, alignment of the individual elements of the beam-shaping optics, as required in the prior art, is no longer necessary. In particular, the micro-optics are made of a transparent polymer. The transparent material is, in particular, an acrylate or an epoxy. Here, "transparent" refers to the material's property of substantially transmitting light in the near-UV, visible wavelength range, and / or near-infrared. "Substantially" means that more than 50% of the light passes through the material, preferably more than 70%, more preferably more than 90%, and most preferably more than 95%. Thus, the beam shaping optics 12 are directly connected to the optical fiber 10. Adjustment of the beam shaping optics 12 relative to the optical fiber 10 is no longer necessary and is achieved through the manufacturing process of the beam shaping optics 12. In particular, the micro-optics have an outer diameter in the range of 50 µm to 1000 µm, and preferably in the range of 200 µm to 500 µm. Specifically, the outer diameter of the beam shaping optics 12 corresponds essentially to the outer diameter of the optical fiber 10. In particular, the beam shaping optics are rotationally symmetric about the optical axis of the optical fiber 10 and the beam shaping optics 12 (common optical axis). However, this depends on the non-Gaussian intensity profile to be achieved. Thus, for non-rotationally asymmetric intensity profiles, the respective beam shaping optics 12 may also be non-rotationally symmetric. In the embodiment shown in Fig. 3A, the exit surface 22 of the beam shaping optics 12 has a freeform surface through which the intensity distribution or the non-Gaussian beam profile is generated. In the embodiment shown in Fig. 3B, the beam shaping optics 12 has a cavity 24. The cavity 24 has an inner surface 28, which is located opposite, or rather points away from, the light exit surface 22. The inner surface 28 of the cavity 24 is designed as a freeform surface to form the non-Gaussian beam profile or intensity profile. Furthermore, the cavity 24 has an opening 26 at the entrance surface 20 of the beam shaping optics 12. The opening 26 is thus located at the core of the optical fiber 10, i.e., at the point of highest intensity of the light exiting the end facet of the fiber 10. By providing the opening 26 at this location, damage to the material of the beam shaping optics 12 can be avoided. In the embodiment shown in Fig. 3C, the cavity 24 has a first inner surface 30 opposite the light-emitting surface 22 and a second inner surface 31 opposite the light-intake surface 20, which points away from the intake surface. In the example shown in Fig. 3C, the second inner surface 31 is designed as a freeform surface for generating the non-Gaussian beam profile or the non-Gaussian intensity distribution. The first inner surface 30 can be designed as a refractive, diffractive, or combined refractive-diffractive surface for further adjustment of the beam profile or, for example, for collimating the emitted light. In the embodiment shown in Fig. 3D, which essentially corresponds to the embodiment shown in Fig. 3B, the beam shaping optics 12 are further surrounded by a sleeve 32. The sleeve 32 completely surrounds both the beam shaping optics 12 and a fiber end 34 of the optical fiber 10. The sleeve 32 can be made of, for example, a metal or plastic material. In particular, the sleeve 32 can be made of a non-transparent material. Naturally, the sleeve does not surround the end facet 18 of the fiber 10, the light entry surface 20, or the light exit surface 22 of the beam shaping optics 12, so that light transmission through the beam shaping optics 12 is always ensured. The sleeve 32 improves the mechanical stability of the beam shaping optics 12 and, in particular, its connection with the optical fiber 10, and protects the beam shaping optics 12 from external mechanical influences. In the embodiments shown in Figures 3B-3D, the light-emitting surface 22 is planar. This allows for easy polishing and / or cleaning of the light-emitting surface. In particular, the respective freeform surface 28, 31 is protected by the beam-shaping optics 12 itself, and, for example, an impact of the light-emitting surface with an object does not necessarily lead to damage to the freeform surface 28, 31. This further increases the robustness of the fiber-coupled optics, and thus, for example, minor damage can be repaired by polishing the light-emitting surface 22 without requiring the replacement of the entire beam-shaping optics 12. The following refers to Figures 4A and 4B. In Figures 4A and 4B, the focusing optics 14 have a zoom lens formed by a first lens 14A and a second lens 14B. Here, for example, the first lens 14A is configured as a diverging lens and the second lens 14B as a converging lens. The beam diameter can be adjusted by changing the distance between the first lens 14A and the second lens 14B, as shown in Figures 4A and 4B. If the distance between the first lens 14A and the second lens 14B is increased as shown in Figure 4B, the beam diameter at the outlet of the second lens 14B increases. Reference is made below to Fig. 5. In this example, the beam-shaping optics 12 are integrated into a ferrule 38, which is arranged at the end of an optical waveguide 36. The optical fiber 10 of the optical waveguide 36 is arranged and fixed within the ferrule 38. Furthermore, the beam-shaping optics 12 are arranged within the ferrule 38 directly at an end opening 40 of the ferrule 38. This ensures that the optical fiber 10 is aligned relative to the beam-shaping optics 12 by the ferrule 38. In particular, the beam-shaping optics 12 can be produced through the opening 40 in the ferrule 38, and subsequently the optical fiber can be inserted into the ferrule and, for example, glued in place. Alternatively, the beam-shaping optics can be produced on the end facet of the optical fiber 10 and then inserted into the ferrule together.In particular, the ferrule is made of metal or ceramic so that the highest possible positioning accuracy of the optical fiber 10 can be achieved, especially relative to the beam shaping optics 12 and the aperture 40. Reference is made below to Fig. 6, which shows an optical fiber 42 with connectors 44 and 46 at its ends. These connectors can, for example, be FC connectors. In the example shown in Fig. 6, a first connector 46 has a ferrule 48 in which an optical fiber 10 is held. Furthermore, a beam-shaping optic 12 is arranged in the ferrule 48 and has an opening 40 through which the light from the optical fiber 10 can exit the ferrule 48 via the beam-shaping optic 12. Thus, connector 46 can be easily connected to an optical apparatus and provides light with a desired non-Gaussian intensity distribution. The light emerging from the optical fiber 10 can then be collimated using a macroscopic lens, as described above. Reference is made below to Figures 7A and 7B. Figures 7A and 7B show an adapter 50, which can be connected to a ferrule 52 of a connector 54. The adapter 50 has a receptacle for receiving the ferrule 52 of the connector 54. Furthermore, the adapter 50 has a recess for receiving the beam-shaping optics 12. The receptacle and recess of the adapter 50 share a common optical axis. By defining the relative positions of the receptacle and the recess, a defined positional relationship between the ferrule 52 of the optical fiber and the beam-shaping optics 12 can be established. In particular, the recess of the adapter 50 for the ferrule 52 is precisely shaped to fit the ferrule 52, ensuring and maintaining an exact positional relationship. Thus, the connector 54 can be easily adapted by attaching the adapter element 50.Different adapter elements can be used, allowing for the creation of various non-Gaussian intensity profiles. The individual adapters can be easily changed, for example, by simply snapping them on, enabling quick switching between non-Gaussian beam profiles. The following refers to the system shown in Figures 8A and 8B. This system includes a connector 46, which can be inserted into and connected to a connecting element 58. Either the connecting element 58, as shown in the adapter shown in Figures 7A and 7B, or the connector 46 itself, as shown in Figure 6, can have a beam-shaping optic 12, which is located directly at the end facet of the optical fiber 10. The system shown in Figures 8A and 8B also includes a housing 56 in which the focusing optic 14 is located. This creates an integrated system for generating a non-Gaussian intensity profile. In the example shown in Figures 8A and 8B, this results in a top-hat intensity profile.

Claims

Fiber-coupled optics for generating a non-Gaussian intensity profile with an optical fiber (10) having an end facet (18), a beam shaping optic (12) which is arranged on the end facet (18), wherein the beam shaping optic (12) is designed as a micro-optics, characterized in that the micro-optics (12) is arranged in an adapter (50), wherein the fiber (10) has a fiber connector and the adapter (50) has a receptacle for receiving the fiber connector (54), wherein the adapter further has a recess, wherein the micro-optics (12) is arranged in the recess of the adapter. Fiber-coupled optics according to claim 1, characterized in that the non-Gaussian intensity profile is a top-hat profile, a donut profile, a rectangular profile, a square profile, a multispot profile or a logo. Fiber-coupled optics according to claim 1 or 2, characterized in that the micro-optics (12) has a diameter in the range of 50µm to 1500µm, preferably 200µm to 500µm. Fiber-coupled optics according to one of claims 1 to 3, characterized in that the micro-optics (12) has a diameter which essentially corresponds to the diameter of the fiber (10). Fiber-coupled optics according to one of claims 1 to 4, characterized in that the micro-optics (12) is produced by means of 3D laser writing and in particular by means of 2-photon laser writing. Fiber-coupled optics according to one of claims 1 to 5, characterized in that the micro-optics (12) are made of a transparent polymer. Fiber-coupled optics according to one of claims 1 to 6, characterized in that the micro-optics (12) are directly produced, attached or glued onto the end facet (18). Fiber-coupled optics according to one of claims 1 to 7, characterized in that the micro-optics (12) is at least partially surrounded by a sleeve (32), wherein in particular a fiber end which has the end facet (18) is also at least partially surrounded by the sleeve (32). Fiber-coupled optics according to one of claims 1 to 8, characterized in that the micro-optics (12) has an entry surface (20) which is arranged in the direction of the end facet (18) and has an exit surface (22) opposite the entry surface (20), so that light from the fiber (10) passes through the entry surface (20) into the micro-optics (12) and exits it via the exit surface (22) or vice versa. Fiber-coupled optics according to claim 9, characterized in that the exit surface (22) is designed as a freeform surface and / or diffractive surface. Fiber-coupled optics according to claim 9, characterized in that the exit surface (22) is designed as a flat surface. Fiber-coupled optics according to one of claims 1 to 11, characterized in that the micro-optics (12) has a cavity (24). Fiber-coupled optics according to claim 12, characterized in that the cavity (24) has at least one inner surface (28), wherein the inner surface (28) is designed as a free-form surface and / or diffractive surface. Optical system for generating a non-Gaussian intensity profile with a fiber-coupled optic according to one of claims 1 to 13 and a focusing optic (14) with at least one lens. Optical system according to claim 14, characterized in that the at least one lens has a diameter in the range of 10mm to 50mm, preferably in the range of 20mm to 30mm. Optical system according to claim 14 or 15, characterized in that the distance between the fiber-coupled optics and the focusing optics (14) is between 50mm and 200mm. Optical system according to one of claims 14 to 16, characterized in that the distance between the fiber-coupled optics and the focusing optics (14) corresponds essentially to the focal length of the focusing optics (14). Adapter for connection to a fiber connector, with an adapter element (50), wherein the adapter element has a receptacle for receiving a fiber connector and a recess, wherein a beam shaping optic (12) for generating a non-Gaussian intensity profile is arranged in the recess, wherein the beam shaping optic (12) is designed as a micro-optic.

Images