Modular deflection units in a mirror-symmetrical arrangement
The symmetrical arrangement of deflection units in the deflection module addresses space and design inefficiencies in additive manufacturing, enabling compact and efficient parallel laser processing with reduced costs and improved accuracy.
Patent Information
- Authority / Receiving Office
- DE · DE
- Patent Type
- Utility models
- Current Assignee / Owner
- RAYLASE GMBH
- Filing Date
- 2021-04-19
- Publication Date
- 2026-06-03
Smart Images
Figure 00000000_0000_ABST
Abstract
Description
AREA OF INVENTION
[0001] The present invention relates generally to laser processing technologies, such as additive manufacturing. In particular, the invention relates to an optical deflection module and to an optical modular deflection system with paired, mirror-symmetrically designed deflection units for improved coordinated operation and increased compactness. BACKGROUND OF THE INVENTION
[0002] Additive manufacturing processes, in which a material is applied layer by layer and thermally processed to form a component, are gaining increasing importance in industrial production compared to classic subtractive manufacturing processes such as milling, drilling, and turning, in which a component is produced by removing material from a raw part. The layer-by-layer manufacturing process characteristic of additive manufacturing enables the production of highly complex geometric structures with a high degree of design freedom that cannot be achieved with subtractive methods.
[0003] The increasing industrial importance of additive manufacturing processes is driven by the rising efficiency of light sources used for the thermal processing of raw materials. Accordingly, the market is currently undergoing a transition from the use of additive manufacturing for prototype production ("rapid prototyping") to the mass industrial application of this technology for series production ("rapid manufacturing"). This development can be observed in numerous technology sectors, such as the aerospace industry, the automotive industry, medical technology, and prosthetics.
[0004] A special type of additive manufacturing is based on powder bed fusion processes, in which a powdered starting material is applied layer by layer to the component to be manufactured and melted and processed by a working light beam, typically a laser beam. The powder layers are typically in the micrometer range in thickness. Deflection units are used to deflect the laser light in a controlled manner to melt the powdered starting material at a series of target positions according to a predefined process, thus forming the desired workpiece.
[0005] Deflection units typically consist of galvanometers, i.e., mirrors movable around an axis that deflect the laser light in different directions by reflecting it at appropriate angles. By combining two mirrors movable around two axes perpendicular to each other, the laser light can be scanned over a two-dimensional work area. The movement of the galvanometer mirror(s) of such deflection units around their respective axes is driven by a precision galvanometer motor. The mirrors are usually attached to a permanent magnet configured to inductively interact with a coil wound in the corresponding galvanometer motor when an electric current flows through the coil. In many applications, the galvanometer motors are significantly larger than the mirrors, resulting in increased space requirements and design challenges.
[0006] The ability to simultaneously form or laser-process a component using multiple laser devices plays a crucial role in increasing the efficiency of powder bed-based additive manufacturing systems for components in technologies such as direct powder fusion, vapor photopolymerization, or directed energy deposition. Such parallelization enables higher output rates. However, the advantages of using multiple laser devices simultaneously for processing a component (parallelization) must be weighed against the aforementioned space requirements and the design challenges associated with using numerous deflection mirrors.
[0007] Therefore, there is a need for improvement in the field of additive manufacturing of components with regard to deflection devices for the parallel processing of a component by several laser devices.
[0008] US Patent 2019 / 0283332 A1 describes an additive manufacturing device comprising a plurality of optical modules configured to direct lasers generated by a plurality of laser modules to melt powder. Each optical module includes a pair of pivotable mirrors. In each optical module, one mirror is pivotable to direct a laser beam in an X direction, and the other pivotable mirror is pivotable to direct the laser beam in a Y direction perpendicular to the X direction.
[0009] From US patent 2019 / 310463 A1, two deflection units are known which are arranged side by side in such a way that their working areas overlap with a common working area which can be processed jointly and simultaneously by both deflection units.
[0010] US 2017 / 173883 A1 describes the use of a lower-power laser beam to melt a powder-based building material in synchronization with a higher-power laser beam used to preheat the powder-based building material. SUMMARY OF THE INVENTION
[0011] The present invention overcomes the aforementioned technical disadvantages and provides a solution based on a deflection module according to claim 1 and a modular deflection system according to claim 19. Preferred embodiments of the invention are defined in the attached dependent claims.
[0012] A deflection module according to the present invention comprises a first deflection unit and a second deflection unit. Each deflection unit comprises a deflection device configured to deflect a respective working beam over a corresponding working field: The first deflection unit comprises a first deflection device configured to deflect a first working beam over a first working field, and the second deflection unit comprises a second deflection device configured to deflect a second working beam over a second working field. The working beam can be a light beam for processing one or more workpieces, in particular a laser beam for laser processing of one or more workpieces, for example in an additive manufacturing process or in other laser processes such as welding or laser marking.
[0013] Each of the deflection devices can be a galvanometer deflection device. In preferred embodiments, the first deflection device can comprise a first movable mirror for deflecting the first working beam in a first direction by pivoting about a first axis, and a second movable mirror for deflecting the first working beam in a second direction by pivoting about a second axis. The first axis can be perpendicular to the second axis. The second deflection device can comprise a first movable mirror for deflecting the second working beam in the first direction by pivoting about a third axis, and a second movable mirror for deflecting the second working beam in the second direction by pivoting about a fourth axis. The third axis can be perpendicular to the fourth axis and / or parallel to the first axis.
[0014] In other embodiments, one or both of the first and second deflection devices can comprise a movable mirror for deflecting the corresponding working beam in the first direction and in the second direction by pivoting about two different corresponding axes, preferably two mutually perpendicular axes. According to the invention, embodiments are also provided in which one of the deflection devices comprises a first movable mirror and a second movable mirror, each movable about a corresponding axis, as described above, and the other of the deflection devices comprises a single movable mirror that is movable about two axes.Although the invention is described here mainly with reference to embodiments in which each of the deflection devices comprises a first movable mirror and a second movable mirror, the principles of the invention apply equally to embodiments in which at least one of the first and second deflection devices comprises a movable mirror for deflecting the corresponding working beams in two directions by pivoting about respective axes. In particular, all features regarding the mutual arrangement and spacing of the second movable mirrors of different deflection units can also apply to the mutual arrangement and spacing of the movable mirrors (each movable about one or two axes) of different deflection units in corresponding embodiments.
[0015] In each case, each of the first and second deflection units is configured to deflect the respective working beam in two independent and distinct directions: the first direction and the second direction. This allows the first and second working beams to be deflected across corresponding two-dimensional working fields, the first working field and the second working field. The first direction can be perpendicular to the second direction. For example, the first direction can correspond to an x-direction and the second direction to a y-direction in a Cartesian coordinate system. However, a person skilled in the art will understand that the choice of coordinates is arbitrary, so the first direction can correspond to a y-direction and the second direction to an x-direction.
[0016] The first and second deflection units can have a similar or identical structure and similar or identical optical components. Each of the first and second deflection units can further comprise a light source, in particular a laser source, for generating the corresponding working beam. Thus, the first and second working beams can be generated independently of each other. In some embodiments, however, the same light source can be connected to both the first and second deflection units to generate both the first and second working beams.
[0017] According to some embodiments, particularly when one or both of the first and second deflection devices comprise first and second movable mirrors, the second movable mirror of the first deflection device can be arranged along the beam path of the first working beam in the direction of the first working field downstream of the first movable mirror of the first deflection device. In other words, as the first working beam propagates towards the first working field, it can first be reflected by the first movable mirror of the first deflection device and then by the second movable mirror of the first deflection device, so that the second movable mirror of the first deflection device forms the last point in the optical system where the propagation direction of the first working beam is transferred and / or can be changed before the first working beam reaches the first working field.The second movable mirror of the first deflection device can thus form an optical output window of the first deflection unit.
[0018] Similarly, the second movable mirror of the second deflection device can be arranged along the beam path of the second working beam towards the second working field, downstream of the first movable mirror of the second deflection device. In this way, the second working beam, as it propagates towards the second working field, can first be reflected by the first movable mirror of the second deflection device and then by the second movable mirror of the second deflection device. Thus, the second movable mirror of the second deflection device represents the last point in the optical system where the propagation direction of the second working beam is transferred and / or can be changed before the second working beam reaches the second working field. The second movable mirror of the second deflection device can therefore form an optical output window of the second deflection unit.
[0019] The first working area, which can be deflected by the first working beam deflected by the first deflection unit, and the second working area, which can be deflected by the second working beam deflected by the second deflection unit, have a common overlap area, i.e., an area contained within both the first and second working areas. The common overlap area is an area accessible to both the first and second working beams. Therefore, any point in space within the common overlap area can be processed by either the first or the second working beam. The first and second deflection units can cooperate to efficiently form and laser process one or more workpieces within the common overlap area.The first and second working fields can lie in the same plane, at a specific distance from the last movable mirror along the path of the corresponding working beam, e.g., from the second movable mirror of the first deflection device and / or the second movable mirror of the second deflection device. This distance is called the "deflection radius." The deflection radius can correspond to a distance between the second movable mirror of the first scanning device and / or the second scanning device and the corresponding working field along the vertical z-direction, i.e., a distance between the second and / or fourth axis and the respective working field in the vertical direction (z-direction).
[0020] In the deflection module according to the invention, the second movable mirror of the first deflection device and the second movable mirror of the second deflection device (or the movable mirror of the first deflection device, which is movable about two axes, and the movable mirror of the first deflection device, which is movable about two axes) can be arranged symmetrically to each other and to a common plane of symmetry. Furthermore, the second axis about which the second movable mirror of the first deflection device is rotatable for deflecting the first working beam in the second direction, and the fourth axis about which the second movable mirror of the second deflection device is rotatable for deflecting the second working beam in the second direction (or the respective axes of the mirrors movable about two axes) can be aligned with each other, i.e., lie on the same line.Consequently, the first working field and the second working field can be aligned with each other, particularly in the second direction and / or in a direction perpendicular to the common plane of mirror symmetry. The second and fourth axes (or the respective axes of mirrors movable about two axes) can, in particular, be perpendicular to the common plane of mirror symmetry and aligned with each other, such that the second movable mirror of the first deflecting device and the second movable mirror of the second deflecting device can be movable about the same axis of rotation, which is arranged perpendicular to the common plane of mirror symmetry.
[0021] The symmetrical and aligned arrangement according to the invention of at least the second movable mirrors of the first and second deflection device as well as the second and fourth axes enables a very compact arrangement of the deflection module, in particular with regard to the integration of the first deflection unit and the second deflection unit within a single deflection module for cooperative use of the first and second working beam for simultaneous laser processing.The mirror-symmetrical arrangement of the invention allows the distance between the second movable mirror of the first deflection device and the second movable mirror of the second deflection device, and in particular the distance between an optical center of the second movable mirror of the first deflection device and an optical center of the second movable mirror of the second deflection device, to be reduced to a minimum, while avoiding overlaps or interference of one of the optical components by other optical components. For example, the possibility of collisions between the second movable mirror of the first deflection device and the second movable mirror of the second deflection device during their operation is avoided.
[0022] The term "optical center" here refers to the center of the beam path defined by the respective deflection unit for the corresponding working beam, when the working beam is directed vertically downwards in the z-direction, and / or to the geometric center of the corresponding working field. The movable mirrors are arranged such that when a working beam is reflected by a corresponding movable mirror and deflected towards the center of the corresponding working field, the working beam is reflected at and around its optical center, depending on a cross-sectional intensity distribution and / or the spot size of the working beam.For example, if a working beam with a Gaussian intensity distribution is reflected in its cross-section by a movable mirror and deflected towards the center of the corresponding working field, the center (the maximum) of the intensity distribution is reflected precisely at the "optical center" of the movable mirror. The distance between the second movable mirror of the first deflection device, in particular its optical center, and the second movable mirror of the second deflection device, in particular its optical center, can be as small as the assembly and / or handling requirements allow. The same applies to the spatial distance between the edges of the second movable mirror of the first deflection device and the second movable mirror of the second deflection device.
[0023] The reduced distance between the second movable mirrors of the first and second deflection devices further enables the size of the common overlap area to be maximized, allowing the first and second deflection units to work together simultaneously without increasing the deflection radius. Such an increase would otherwise lead to increased inaccuracy, particularly at the edges of the processing fields where the movable mirrors operate at their largest angles of inclination. The reduced deflection radius also allows the deflection module according to the invention to be integrated into a laser processing system with a reduced overall vertical dimension. The deflection module according to the invention thus represents a compact, easily transportable, and shippable solution for parallelized laser processing, which is advantageous with regard to fast and satisfactory customer service.The deflection module according to the invention thus offers an improved balance between compactness and high yield / productivity, which is achieved through the simultaneous action of several working beams.
[0024] The first and second deflection devices can be rigidly connected to each other, so that a relative spatial position of the first deflection device in relation to the second deflection device, in particular the respective movable mirrors, can be determined.
[0025] According to some embodiments of the invention, each of the first and second deflection devices can further comprise a galvanometer motor for pivoting the respective second movable mirror. The first deflection device can comprise a first galvanometer motor for pivoting the second movable mirror of the first deflection device, and the second deflection device can comprise a second galvanometer motor for pivoting the second movable mirror of the second deflection device. The first and second deflection devices can further comprise or be connected to corresponding control units that control the operation of the galvanometer motors and thus a corresponding pivoting movement of the respective second movable mirror.The first movable mirrors of the first and second deflection devices can also be connected to corresponding galvanometer motors that control their swiveling movement, and optionally to control units that monitor their operation.
[0026] The mirror-symmetric and aligned arrangement of at least the second movable mirrors according to the invention makes it possible to arrange the first galvanometer motor and the galvanometer stepper motor on opposite sides of the respective second movable mirror with respect to the common plane of mirror symmetry, so that the first galvanometer motor and the second galvanometer motor are arranged mirror-symmetrically to each other and to the common plane of mirror symmetry, maintaining a minimal distance between the second movable mirrors. Although the galvanometer motors are relatively bulky components, the arrangement according to the invention allows them to be positioned in a space-saving manner, so that they do not touch each other, do not impair the movement of other optical components, in particular the movable mirrors, and do not block any beam path within the deflection module.
[0027] The first and second galvanometer motors can be arranged such that they extend substantially perpendicular to the common plane of mirror symmetry, in particular from a first end near the corresponding second movable mirror to a second end opposite the corresponding second movable mirror (and the common plane of mirror symmetry). The second movable mirror of the first deflection device can therefore be arranged in a direction substantially perpendicular to the common plane of mirror symmetry between the first galvanometer motor and the common plane of mirror symmetry, while the second movable mirror of the second deflection device can be arranged in said direction substantially perpendicular to the common plane of mirror symmetry between the second galvanometer motor and the common plane of mirror symmetry.Furthermore, the first galvanometer motor can be aligned with the second galvanometer motor in the aforementioned direction essentially perpendicular to the common mirror symmetry plane.
[0028] It should be noted that the axis of rotation of the first and second galvanometer motors does not necessarily have to coincide with the respective axis of rotation of the corresponding second movable mirror, although this may be the case in some embodiments. The axis of rotation of the first and / or second galvanometer motor can be arranged parallel to—with an offset—the respective second or fourth axis, or at an angle of up to 15° to it.
[0029] Although the mirror symmetry and alignment of the deflection module according to the invention are formed at least by the second movable mirrors of the first and second deflection devices, further components of the first and second deflection units can have the same mirror symmetry – with respect to the same common plane of mirror symmetry – and / or be aligned with or parallel to each other. For example, the first movable mirror of the first deflection device and the first movable mirror of the second deflection device can be arranged in a mirror-symmetrical manner with respect to each other and to the common plane of mirror symmetry. However, the first axis can be arranged substantially parallel to the third axis, with the first and third axes being arranged substantially parallel to the common plane of mirror symmetry, for example, aligned in the vertical z-direction or arranged with an inclination of approximately 0° to approximately 15° relative to the vertical z-direction.
[0030] In some embodiments, the first and third axes can be arranged parallel to each other and to the common plane of mirror symmetry or perpendicular to the second and fourth axes, and the second and fourth axes can be aligned to each other and arranged perpendicular to the common plane of mirror symmetry and to the first and third axes.
[0031] According to some embodiments, the first working beam can strike the first deflecting device, in particular its first movable mirror, and propagate in a first direction of incidence perpendicular to the common plane of symmetry of the mirrors, and the beam path of the second working beam can strike the second deflecting device, in particular its first movable mirror, and propagate in a second direction of incidence perpendicular to the common plane of symmetry of the mirrors, wherein the first direction of incidence can be aligned with and opposite to the second direction of incidence. Thus, the first working beam and the second working beam can lie in the same line at least until they reach their respective deflecting devices.
[0032] According to some embodiments, the first deflection unit and the second deflection unit can be arranged in a mirror-symmetrical manner with respect to the common plane of mirror symmetry and / or with respect to each other, such that the path of the first working beam, at least before deflection by the first deflection device, and the path of the second working beam, at least before deflection by the second deflection device, are mirror-symmetrical with respect to each other and to the common plane of mirror symmetry. Thus, the path followed by the first working beam within the first deflection unit, at least until the first working beam is deflected by the first deflection unit, can be mirror-symmetrical to the path followed by the second working beam within the second deflection unit, at least until the second working beam is deflected by the second deflection unit.Thus, the beam path followed by the first working beam in the first deflection unit and the beam path followed by the second working beam in the second deflection unit can be mirror images of each other with respect to the common plane of mirror symmetry.
[0033] The “mirror symmetry” of the first and second deflection units with respect to each other can refer to the position and / or the settings of each of their optical components, such as mirrors and lenses, and to the corresponding light path lengths that they define for the respective working beam, especially when the orientation and / or setting of each of the optical components of the first deflection unit – with which the first working beam interacts on its way to the first working beam – corresponds to the corresponding orientation and / or setting of the respective optical components of the second deflection unit – with which the second working beam interacts on its way to the second working field – where the latter optical components can be a mirror image of the former components with respect to the common mirror symmetry plane.“Settings” can refer to the optical properties of an optical component, such as focal length, diameter or size, shape, aperture, etc. For example, a first optical lens of the first deflection unit, arranged so that it is a mirror image of a second optical lens of the second deflection unit with respect to the common plane of mirror symmetry, may have the same focal length, size, and shape as the second optical lens.
[0034] However, mirror symmetry does not necessarily mean that the first and second deflection units must always be configured to maintain this symmetry with respect to all optical components and settings at all times, especially with respect to the first and second deflection devices, which can operate independently of each other. For example, it is not necessary that whenever the first deflection unit, using the first deflection device, directs the first working beam to a point in the first working field, the second deflection unit, using the second deflection device, correspondingly directs the second working beam to a point in the second working field that is a mirror image of the first working beam with respect to the axis of mirror symmetry.Instead, the first and second deflection units can be configured to operate independently, so that their optical components, especially the lenses and / or mirrors of the first and second deflection devices, can assume different positions and orientations during operation, which can break the general mirror symmetry of the deflection module.
[0035] For example, the inclination of the first movable mirror about the first axis at any given time may differ from the inclination of the first movable mirror about the third axis (i.e., not be a mirror image of the same), and the inclination of the second movable mirror about the second axis may differ from the inclination of the second movable mirror about the fourth axis if they are arranged symmetrically to each other and to a common plane of symmetry.
[0036] In some embodiments, the path of the first working beam, before deflection by the first deflection device, can be aligned with the path of the second working beam, before deflection by the second deflection device, in a direction perpendicular to the common mirror symmetry plane. In other words, the first working beam and the second working beam, before deflection by their respective deflection devices, can be coplanar, i.e., lie in a common plane, where the common plane can, in particular, be perpendicular to the common mirror symmetry plane.This allows for a particularly compact arrangement, as both the first working beam - and the corresponding optical elements that define a beam path of the first working beam at least up to the first deflection device - and the second working beam - and the corresponding optical elements that define a beam path of the second working beam at least up to the second deflection device - are arranged in one plane, which can allow a reduction in the width of the deflection module and thus its volume.
[0037] According to some embodiments of the invention, the distance between the second movable mirror of the first deflection device and the second movable mirror of the second deflection device may not exceed 1 / 3 of the diameter of the second movable mirror of the first deflection device and / or the second movable mirror of the second deflection device, preferably not more than 1 / 4 thereof, and particularly preferably not more than 1 / 5 or 1 / 6 thereof. "Distance" here may refer to the shortest definable Euclidean distance.The distance between the second movable mirror of the first deflection unit and the second movable mirror of the second deflection unit can be the distance between an edge of the second movable mirror of the first deflection unit and an edge of the second movable mirror of the second deflection unit in a direction perpendicular to the common plane of mirror symmetry, in particular in the direction in which the second and fourth axes extend. In some embodiments, the diameter of the second movable mirror of the first deflection unit can be equal to the diameter of the second movable mirror of the second deflection unit. The term "diameter," as used here for mirrors, can refer not only to the size of movable mirrors of a circular shape, but to any geometric quantity that defines the length of a principal axis of the respective movable mirror.If a movable mirror has an oval or elliptical shape, the "diameter" can refer to the major or minor axis. If a movable mirror has a square or rectangular shape, the term "diameter" used here can refer to the length or width of the mirror.
[0038] According to some embodiments, the shape and size of the second movable mirror of the first deflection device and the second movable mirror of the second deflection device can be the same. Regardless of whether the second movable mirrors of the first and second deflection devices are identical in shape and size, each of them can have a circular, elliptical, square, rectangular, rhombic, or polygonal shape, particularly its reflective surface. The second movable mirrors can be arranged such that the corresponding axis about which the movable mirror is pivotable, for example, when driven by a galvanometer motor, coincides with a principal axis of the movable mirror.If the second movable mirrors are elliptical, for example, the second and fourth axes can be aligned with the principal axes of the ellipses defined by the second movable mirrors (and with each other). If the second movable mirrors are rectangular, the second and fourth axes can be aligned with the longitudinal axis of symmetry of the rectangle formed by the second movable mirrors (and with each other). If the second movable mirrors are circular, the second and fourth axes can be aligned with the diameter of the circle defined by the second movable mirrors (and with each other).
[0039] Similar considerations can apply to the first movable mirrors of the first and second deflection devices, whereby the first movable mirrors can be arranged such that the corresponding axis about which the movable mirror is pivotable, for example when driven by a suitable galvanometer motor, coincides with a minor axis of the movable mirror. If the first movable mirrors are elliptical, for example, the first and third axes can be aligned with the minor axes of the ellipses defined by the first movable mirrors (and with each other). If the first movable mirrors are rectangular, the first and third axes can be aligned with the shorter axis of symmetry of the rectangle defined by the first movable mirrors.
[0040] In some embodiments, the diameter of the second movable mirror of the first deflection device and / or the second movable mirror of the second deflection device can be between 5 mm and 50 mm, preferably between 10 mm and 40 mm, and even more preferably between 20 mm and 30 mm. The same considerations can apply to the first movable mirrors of the first and second deflection devices.
[0041] According to some embodiments of the invention, the distance between an optical center of the second movable mirror of the first deflection device and an optical center of the second movable mirror of the second deflection device may not be more than four times the aperture of the first movable mirror of the first deflection device and / or the first movable mirror of the second deflection device, preferably not more than three times that aperture, and particularly preferably not more than 2.5 times or twice that aperture.
[0042] In embodiments where the second movable mirror of each of the first and second deflection devices is arranged behind the corresponding first movable mirror, the "aperture" of the respective first movable mirror can refer to the extent (diameter) of the respective first movable mirror in a direction parallel to the corresponding axis of rotation, i.e., the first or third axis. For example, if a first movable mirror has an oval or elliptical shape, the aperture can correspond to the minor axis of the oval or ellipse. If the first movable mirror has a square or rectangular shape, the aperture can correspond to the shorter side or "width." The aperture of the first movable mirrors can be defined for beams with a specific beam diameter, e.g., with a specific 1 / e 2 -diameter, designed to be
[0043] The dimensions of the corresponding second movable mirrors can be designed such that they reflect working rays of a specific diameter, e.g., a specific 1 / e 2-diameter, reflect after being reflected by the corresponding first movable mirror at a specific angle of incidence. If a second movable mirror, for example, has an oval or elliptical shape, its principal axis, which may be aligned with the corresponding axis of rotation, i.e., the second or fourth axis, may be dimensioned to reflect the working beam coming from the respective first movable mirror, taking into account the distance between the first and second movable mirrors and the range of possible angles of incidence of the working beam on the second movable mirror as a function of an inclination angle of the respective first movable mirror. The dimensions of the second movable mirror may further be determined by working beams of a specific beam diameter, e.g., a specific 1 / e 2 -Diameter, can be adjusted.
[0044] The dimensions of the second movable mirror, particularly its diameter, can be larger than the dimensions of the corresponding first movable mirror. For example, if both the first and second movable mirrors are oval-shaped, the minor axis of the second movable mirror can be larger than the minor axis of the first movable mirror.
[0045] Assuming a Gaussian distribution of the intensity profile of the working beams in their cross-sections, for example the first working beam can be assigned a first 1 / e 2- Beam diameter on the first deflecting device, in particular on the first movable mirror of the first deflecting device, and the second working beam with a second 1 / e 2- Beam diameter falling on the second deflection device, in particular on the first movable mirror of the second deflection device. The second beam diameter can preferably be equal to the first beam diameter. The aperture of the first movable mirror of the first deflection device and / or the aperture of the first movable mirror of the second deflection device can be defined here such that it is at least 1.1 times, preferably at least 1.3 times, particularly preferably at least 1.5 times the respective 1 / e 2 - beam diameter corresponds to this. For example, a first and a second working beam can be 1 / e 2 - Beam diameter of 20 mm each, the corresponding apertures of the respective first movable mirrors 30 mm (1.5 times the 1 / e 2 - beam diameter) and the corresponding distance between the optical centers of the respective second movable mirrors can be 75 mm.
[0046] In some embodiments, the distance between the optical center of the second movable mirror of the first deflection device and the optical center of the second movable mirror of the second deflection device is no more than 120 mm, preferably no more than 80 mm, and particularly preferably no more than 60 mm.
[0047] According to some embodiments, the distance between the second movable mirror of the first deflection device and the second movable mirror of the second deflection device is no more than 1 / 3 of the aperture of the first movable mirror of the first deflection device and / or the second deflection device, preferably no more than 1 / 4 thereof, and particularly preferably no more than 1 / 5 or 1 / 6 thereof.
[0048] In some embodiments, the distance between the second movable mirror of the first deflection device and the second movable mirror of the second deflection device is no more than 50 mm, preferably no more than 30 mm and even more preferably no more than 10 mm.
[0049] The first and second working areas can each cover an area of 100 mm x 100 mm to 1000 mm x 1000 mm, preferably 300 mm x 300 mm to 700 mm x 700 mm, and particularly preferably 400 mm x 400 mm to 600 mm x 600 mm. The first and second working areas can have the same shape and size. The first and second working areas can be aligned with each other in a direction parallel to the common plane of symmetry such that they have the same distance and extent in this direction parallel to the common plane of symmetry, i.e., they extend in this direction from a first common vertex to a second common vertex.In the direction mentioned, parallel to the common plane of mirror symmetry, the common overlapping surface can therefore have an extent that corresponds to 100% of the extent that the first and / or second working field has in the direction mentioned, parallel to the common plane of mirror symmetry.
[0050] In some embodiments of the invention, the first and second working fields can partially overlap in an overlap direction perpendicular to the common mirror symmetry plane, wherein the common overlap area can have an extent in the overlap direction that corresponds to at least 75%, preferably at least 80%, particularly preferably at least 90% of the extent covered by the first and / or second working field in the overlap direction.The common overlap area can thus have an extent in the overlap direction of 75 mm to 900 mm and an extent in a direction parallel to the common mirror symmetry plane of 100 mm to 1000 mm, preferably an extent in the overlap direction of 225 mm to 630 mm and an extent in a direction parallel to the common mirror symmetry plane of 300 mm to 700 mm, even more preferably an extent in the overlap direction of 300 mm to 540 mm and an extent in a direction parallel to the common mirror symmetry plane of 400 mm to 600 mm. The common overlap area can, for example, be 400 mm x 500 mm.
[0051] While other solutions known from the prior art rely on increasing the deflection radius to operate multiple deflection units on a common working area of overlapping fields, the inventors of the present invention have recognized that, through the symmetrical arrangement and design of the first and second deflection units according to the invention, small distances between the second movable mirrors of the first and second deflection devices and / or their optical centers—especially distances within the aforementioned areas—can be achieved in combination with the aforementioned areas of the common overlap region, while maintaining a compact deflection module and, in particular, without increasing the deflection radius. By avoiding an increase in the deflection radius, a large common overlap region of the working areas of different deflection units can be achieved without increasing the deflection radius.
[0052] According to some embodiments of the invention, the height of the second movable mirror of the first deflection device above the first working field and / or the height of the second movable mirror of the second deflection device above the second working field, i.e., the respective scanning radii, may not exceed 800 mm, preferably not more than 600 mm, and particularly preferably not more than 400 mm. The height of the second movable mirror of the first deflection device above the first working field and the height of the second movable mirror of the second deflection device above the second working field may be the same. By combining the symmetrical arrangement of the components of the first and second deflection units according to the invention with small distances between the second movable mirrors of the first and second deflection devices, in particular distances within the aforementioned ranges, scanning radii within the aforementioned ranges can be achieved.The aforementioned scanning radii can be achieved by the first and second deflection units by appropriately adjusting the focal length of their respective optical systems, so that the first and second working beams are focused on the first and second working fields respectively, i.e., at distances from the respective deflection device that correspond to the aforementioned scanning radii.
[0053] In this respect, the invention enables the combination of the technical advantages of a large common overlap area in which the first deflection unit and the second deflection unit can work together to process one or more workpieces simultaneously with the laser, and a reduced deflection radius, which leads to a more compact design and higher optical accuracy, for example due to a lower inclination of the working beams when laser processing a workpiece in the edge areas of the respective working fields.
[0054] Furthermore, the deflection module according to the invention enables a reduced working volume (i.e., the three-dimensional vertical projection of the working fields, in particular the common overlap area) due to a reduced deflection radius. If a fluid flow through the working volume is used to remove gaseous residues from the laser processing of the workpiece within the working volume, which could otherwise negatively affect the laser work by absorbing some of the light from the working beams, the required amount of fluid in the working volume can be reduced due to the smaller working volume. The fluid flow can, for example, be an inert gas flow, such as argon, which makes it possible to suppress oxidation of the material used to shape the workpiece, e.g., metal powder, during laser processing.Reducing the required amount of inert gas significantly reduces the overall cost of the laser processing process, given the high cost of inert gases. Furthermore, the reduced working volume allows for better control of fluid flow behavior within the working volume, such as the formation of turbulence.
[0055] In some embodiments, the deflection module can further comprise a housing, in which the first and second deflection units can be enclosed. The housing, which can be made, for example, of aluminum and / or stainless steel, is preferably waterproof and / or dustproof. This reduces thermal displacement of the optical components of the deflection module that can be caused by the accumulation of dust, dirt, moisture, and / or water, while maintaining the operating accuracy and sharpness of the deflection module due to the sealing effect of the housing. Furthermore, the housing can protect the deflection module during transport or maintenance, thereby promoting the advantageous modular design and easy interchangeability of the deflection module according to the invention.
[0056] According to some embodiments, the housing can have a first transparent window configured to allow the first working beam, propagating from the first deflection device to the first working field, to pass through, and a second transparent window configured to allow the second working beam, propagating from the second deflection device to the second working field, to pass through. The first transparent window can be located below the second movable mirror of the first deflection device and aligned with it in a vertical direction (i.e., in a z-direction perpendicular to the first working field), so that the first transparent window can thus form an optical output window of the first deflection unit, through which the first working beam last passes before reaching the first working field.The second transparent window can be positioned below the second movable mirror of the second deflection device and aligned with it in a vertical direction (i.e., in a z-direction perpendicular to the second working field), so that the second transparent window can thus form an optical output window of the second deflection unit, through which the second working beam is last passed before reaching the second working field. The first transparent window and / or the second transparent window can consist of a single glass plate. In some embodiments, the first transparent window and the second transparent window can be rigidly connected. For example, the first transparent window and the second transparent window can be formed by one and the same glass plate.
[0057] The first and second transparent windows can be positioned side by side. Additionally or alternatively, the first and second transparent windows can be adjacent to the same side wall of the enclosure, so that the first and second transparent windows and said side wall of the enclosure, which can be oriented perpendicular to the first and second transparent windows, can share a common edge. As explained below, this configuration has the advantage that the first and second transparent windows of one deflection module are positioned next to the first and second transparent windows of another deflection module when both deflection modules abut each other with their respective side walls (the side wall adjacent to the respective first and second transparent windows).
[0058] According to some embodiments, the first deflection unit and / or the second deflection unit can further comprise an optical element, preferably a dichroic and / or reflective mirror, to at least partially reflect light in a first wavelength range of the first and / or second working beam, wherein the respective deflection device is arranged in the beam path of the corresponding working beam between the corresponding working field and the corresponding optical element, so that the corresponding working beam propagates to the corresponding deflection device and is reflected by the corresponding optical element. The optical element can thus act as a deflector / reflector for the corresponding working beam in order to deflect the working beam coming from a first direction, for example from an entrance window and / or from a laser light source, in a second direction, in particular towards the corresponding deflection device.
[0059] For example, if a working beam (the first and / or second working beam) is generated by a light source positioned relative to the respective working field such that the working beam exits the light source and propagates in a vertical direction (z-direction), i.e., perpendicular to the respective working field, the optical element can be positioned at an angle of 45° to the vertical direction such that the working beam is deflected from the vertical direction into a horizontal direction (e.g., x- and / or y-direction) so that it reaches the deflection device in the horizontal direction. However, other configurations are also possible. In particular, the working beam (the first and / or second working beam) can also be generated by a light source positioned relative to the respective working field such that the working beam propagates in a horizontal direction (e.g.,x- and / or y-direction) or in a diagonal direction with a vertical component and a horizontal component exiting the light source.
[0060] The optical element can further be configured to at least partially transmit light in a second wavelength range of the first and / or second working beam. This allows the respective deflection unit to define a detection beam path followed by a detection beam in the second wavelength range, for example, from the corresponding working field to a corresponding detection device. Thus, as the detection beam propagates from the working field, it is directed (transmitted) to the detection device instead of being reflected back to the light source. The detection beam can then propagate from the corresponding working field to the corresponding detection device, being reflected by the corresponding deflection device and transmitted by the corresponding optical element.
[0061] The optical element can be used as a reflector to redirect the working beam, formed by light in the first wavelength range (e.g., between 1000 nm and 1100 nm), towards the corresponding deflection device on its way to the work area. Simultaneously, the optical element can also be used as a transmitting element, allowing a detection beam originating from the work area and formed by light in the second wavelength range (e.g., below 1000 nm or above 1100 nm) to pass through to a detection unit configured to detect the detection beam. The detection beam can be used to obtain information about the workpiece being processed and thus to monitor the laser processing and / or the conditions of the laser processing by the working beams.For example, the detection beam can be used to calibrate and / or synchronize the working beams.
[0062] The optical element can therefore decouple a working beam from the corresponding detection beam, allowing their optical settings to be controlled independently, as explained in European patent application EP 3 532 238 A1 (e.g., in paragraphs
[0018] and
[0019] ). In this way, imaging errors of the detection beam can be avoided and the monitoring functions can remain focused. The detection unit can comprise an optical sensor, an optical camera, a diode, a pyrometric device, an optical coherent tomography detector, and the like. The optical element and the detection unit can each correspond to an optical element and a detection device as described in European patent application EP 3 532 238 A1.
[0063] According to some embodiments, the first deflection unit and / or the second deflection unit may further comprise a focusing device for focusing, zooming, and / or collimating the respective working beam. The focusing device may be arranged along the beam path followed by the respective working beam, in front of the respective deflection device and in front of the respective optical element. The focusing device may have a variable focal length. The focusing device may comprise a first fixed lens, a first movable lens, and a further fixed or movable lens. In particular, the focusing device may correspond to a focusing device as described in EP 3 532 238 A1. The person skilled in the art should understand that each of the aforementioned “lenses” may be formed by a corresponding group of lenses and need not be formed by a single lens.The focusing device can be designed to adjust the focal length of the respective optical systems (i.e., the first or second deflection unit) so that the first or second working beam is focused on the first or second working field, i.e., at distances from the corresponding deflection device that correspond to the corresponding deflection radius, in particular a deflection radius in the areas described above.
[0064] Another aspect of the present invention relates to a modular deflection system comprising a first deflection module and a second deflection module, wherein the first deflection module and the second deflection module can correspond to one of the embodiments of a deflection module according to the invention described above. In some embodiments, the first deflection module and the second deflection module can be configured identically or at least similarly, i.e., they can have identical or at least similar or equivalent optical components and settings.
[0065] The first and second deflection modules of the modular deflection system according to the invention can be mounted together or mountable together. In some embodiments, the first and second deflection modules can be configured so that they can be detachably attached to one another. When the first and second deflection modules are attached to one another, the common overlapping area of the first deflection module and the common overlapping area of the second deflection module overlap, forming a common overlapping field. The common overlapping field thus forms an overlapping region of the first and second working fields of the first deflection module and the first and second working fields of the second deflection module.
[0066] Up to four deflection units—the first and second deflection units of the first deflection module and the first and second deflection units of the second deflection module—can work together to laser-process one or more workpieces simultaneously within the common overlap area, thereby achieving a high degree of parallelization. At the same time, the compact design of the deflection modules according to the invention allows the overall size of the modular deflection system, particularly its vertical extent, to remain relatively moderate, given the small ratio of the respective scan radii to the respective common overlap areas, which is determined by the configuration of each of the first and second deflection modules. The modular deflection system of the invention thus offers a very compact arrangement of four independent deflection units that can operate simultaneously within the common overlap area to laser-process the same workpiece or workpieces.The modular deflection system can benefit from all the above-mentioned technical advantages of the deflection module according to the invention.
[0067] The compact design of the deflection modules according to the invention makes it possible to attach the first deflection module and the second deflection module to each other in such a way that their deflection devices, in particular the second movable mirrors, can be arranged very close to each other.
[0068] Furthermore, the modular design of the modular deflection system according to the invention enables improved design flexibility and reduced maintenance. For example, if one of the deflection modules of the modular deflection system needs to be inspected or repaired by the manufacturer, it can be easily detached from the modular deflection system, replaced with a suitable spare deflection module, and transported to a manufacturer's site, so that the modular deflection system can continue to be used at the customer's site and production does not have to be interrupted.
[0069] According to some embodiments, the first and second deflection modules can be mirror-symmetrical to each other when they are attached to one another. When attached, the common plane of mirror symmetry of the first deflection module can be aligned with the common plane of mirror symmetry of the second deflection module.
[0070] The modular and symmetrical design of the modular deflection system according to the invention enables a reduced distance not only between the movable mirrors of the first and second deflection modules, for example between the second movable mirror of the first deflection device of the first deflection module and the second movable mirror of the second deflection device of the first deflection module, but also between a movable mirror of the first deflection module and a movable mirror of the second deflection module, in particular between the second movable mirror of the first deflection module and the second movable mirror of the second deflection module.This is particularly the case when the second movable mirrors of the first and second deflection modules are each offset from a longitudinal axis of the respective deflection module, for example, when the second movable mirror and a corresponding transparent window located below the second movable mirror are positioned adjacent to a side wall of a respective deflection module housing. Having the same situation, essentially a mirror image of it, in the other deflection module of the modular deflection system allows for a small distance between the second movable mirrors of different deflection modules, thus contributing to the compact design of the modular system and an increased ratio of the size of the common overlap field to the scan radii of the modular system.
[0071] According to some embodiments of the invention, the distance between an optical center of the second movable mirror of the first deflection device of the first deflection module and an optical center of the second movable mirror of the first or second deflection device of the second deflection module can correspond to at most four times an aperture of the first movable mirror of the first deflection device and / or the first movable mirror of the second deflection device of the first or second deflection module, preferably at most three times that, and particularly preferably at most two and a half times or twice that.
[0072] According to some embodiments, the distance between the second movable mirror of the first deflection device of the first deflection module and the second movable mirror of the first or second deflection device of the second deflection module may not exceed 1 / 3 of the diameter of the second movable mirror of the first deflection device of the first deflection module and / or the second movable mirror of the first or second deflection device of the second deflection module, preferably not more than 1 / 4 thereof, and particularly preferably not more than 1 / 5 or 1 / 6 thereof, wherein the aperture may be defined as explained above.
[0073] The diameter or aperture of the first or second movable mirror of the first and / or second deflection device of the first deflection module can be equal to the diameter or aperture of the first or second movable mirror of the first and / or second deflection device of the second deflection module. In particular, all four first or second movable mirrors of the modular deflection system can have the same diameter, aperture, size, and / or shape.
[0074] In some embodiments, the distance between the optical center of the second movable mirror of the first deflection device of the first deflection module and the optical center of the second movable mirror of the first or second deflection device of the second deflection module can be greater than the distance between the optical centers of the second movable mirrors of the first or second deflection module, preferably up to 20% greater, more preferably up to 10% greater, and most preferably up to 5% greater. However, the distance between the optical center of the second movable mirror of the first deflection device of the first deflection module and the center of the second movable mirror of the first or second deflection device of the second deflection module can be substantially equal to the distance between the optical centers of the second movable mirrors of the first or second deflection module.The same applies to a distance between the optical center of the second movable mirror of the second deflection device of the first deflection module and the center of the second movable mirror of the first or second deflection device of the second deflection module.
[0075] According to some embodiments, the distance between the optical center of the second movable mirror of the first or second deflection device of the first deflection module and the optical center of the second movable mirror of the first or second deflection device of the second deflection module can be at most 120 mm, preferably at most 80 mm, more preferably at most 60 mm.
[0076] According to some embodiments, the distance between the second movable mirror of the first deflection device of the first deflection module and the second movable mirror of the first or second deflection device of the second deflection module may not exceed 50 mm, preferably not more than 30 mm, and more preferably not more than 10 mm. The distance between the second movable mirror of the first deflection device of the first deflection module and the second movable mirror of the first or second deflection device of the second deflection module may be greater than the distance between the second movable mirrors of the first or second deflection modules, preferably up to 20% greater, more preferably up to 10% greater, and most preferably up to 5% greater. This avoids the risk of collision or interference between second movable mirrors of different deflection modules.
[0077] The first deflection module can comprise a first housing, wherein the first deflection unit and the second deflection unit of the first deflection module are enclosed in the first housing. The first housing can be dustproof and / or waterproof. The second deflection module can comprise a second housing, wherein the first deflection unit and the second deflection unit of the second deflection module can be enclosed in the second housing. The second housing can be dustproof and / or waterproof. The first housing and the second housing can be attached to each other such that the first housing and the second housing are positioned side by side when the first and second deflection modules are attached to each other. The second housing can be a mirror image of the first housing when the first and second housings are attached to each other.
[0078] According to some embodiments, the first housing may have a first transparent window through which the respective first working beam propagates from the first deflection device of the first deflection module into the respective first working field, and a second transparent window through which the respective second working beam propagates from the second deflection device of the first deflection module into the respective second working field. Furthermore, the second housing may have a third transparent window through which the respective first working beam propagates from the first deflection device of the second deflection module into the respective first working field, and a fourth transparent window through which the respective second working beam propagates from the second deflection device of the second deflection module into the respective second working field.The first transparent window, the second transparent window, the third transparent window and / or the fourth transparent window can be arranged adjacent to each other if the first deflection module and the second deflection module are attached to each other.
[0079] In other embodiments, the modular deflection system can comprise a common housing in which the first and second deflection units of the first deflection module and the first and second deflection units of the second deflection module can be enclosed. The common housing can be dustproof and / or waterproof.
[0080] Each of the first and second working areas of the first deflection module and each of the first and second working areas of the second deflection module can cover an area of 100 mm x 100 mm to 1000 mm x 1000 mm, preferably from 300 mm x 300 mm to 700 mm x 700 mm, and particularly preferably from 400 mm x 400 mm to 600 mm x 600 mm. The first and second working areas of the first deflection module can be aligned with each other in a first overlap direction, and the first and second working areas of the second deflection module can also be aligned with each other in this first overlap direction. The first overlap direction can be parallel to the common plane of mirror symmetry of the first and second deflection modules.Furthermore, the first working field of the first deflection module can be aligned with one of the first and second working fields of the second deflection module in a second overlap direction perpendicular to the first overlap direction, and the second working field of the first deflection module can be aligned with the other of the first and second working fields of the second deflection module in the second overlap direction.
[0081] In each of the first and second overlap directions, the common overlap field can have an extent that corresponds to at least 75%, preferably at least 80%, and particularly preferably at least 90% of the extent covered by the first and / or second working field of the first and / or second deflection module in the corresponding overlap direction. Thus, in some embodiments of the invention, the common overlap field in the first and second overlap directions can each have an extent of 70 mm to 800 mm (with an area of 70 mm x 70 mm to 800 mm x 800 mm), preferably 220 mm to 600 mm (with an area of 220 mm x 220 mm to 600 mm x 600 mm), and particularly preferably 300 mm to 540 mm (with an area of 300 mm x 300 mm to 540 mm x 540 mm). The common overlap field can be, for example, B. 330 mm x 330 mm in size.
[0082] An exemplary method for laser processing one or more workpieces can be carried out using a deflection module or a modular deflection system according to one of the previously described embodiments of the invention. Such a method can comprise laser processing of the workpiece with a first working beam, which is deflected by a first deflection unit of the deflection module or the modular deflection system, wherein the first working beam has a first power density. The method further comprises laser processing of the workpiece with the second working beam, which is deflected by a second deflection unit of the deflection module or the modular deflection system, wherein the second working beam has a second power density that is higher than the first power density. "Power density" here refers to the areal power density, i.e., the beam power divided by the unit area of the corresponding working field.The second power density can be 1.5 times, 3 times, 5 times or 10 times higher than the first power density.
[0083] According to the exemplary method, the workpiece is laser-processed with the first working beam with a lower power density, at least in a partial area of the common overlap area (or the common overlap field if the deflection module used is integrated into a modular deflection system according to one of the previously described embodiments of the invention), before or after it is processed with the second working beam with a higher power density.
[0084] This exemplary method thus makes it possible to use the first working beam, deflected by the first deflection unit, in a warm-up phase to heat the material for the formation of one or more workpieces at a lower beam power, before the second working beam, deflected by the second deflection unit, is used for laser processing of the workpiece in areas of the workpiece that were previously heated by the first working beam. Additionally or alternatively, the first working beam, deflected by the first deflection unit, can be used in a cooling phase to gradually cool the material used to form the one or more workpieces by using a lower beam power density after the second working beam, deflected by the second deflection unit, has been used.This allows the thermal fluctuations of the material used to form one or more workpieces to be smoothed or flattened over time by dividing them into more than one progressive phase: for example, heating to a lower temperature by the first working jet, then melting at a higher temperature by the second working jet, and then cooling to a lower temperature by the first working jet. Partial melting can also occur during the heating and / or cooling phases. In this way, the temperature gradients to which the material used to form the workpiece is exposed can be reduced, thus preventing the formation of irregularities due to strong temperature gradients.
[0085] In some embodiments, the first and second working beams can have the same beam power, with the first working beam having a larger spot size than the second. This allows different beam power densities to be achieved with working beams of the same beam power, for example, by using identical laser sources to generate both the first and second working beams. Additionally or alternatively, the first and second working beams can have the same spot size, with the first working beam having a lower beam power than the second. This also makes it possible to achieve different beam power densities using the same spot sizes but different beam powers.
[0086] The aforementioned method can further be carried out with a modular deflection system according to one of the embodiments described above, i.e., a modular deflection system with a first and a second deflection module, each deflection module comprising two deflection units. The method can include laser processing of the workpiece with at least one (of the four available) working beams and laser processing of the workpiece with the remaining working beams.For example, the first working beam deflected by the first deflection unit of the first deflection module and the first working beam deflected by the first deflection unit of the second deflection module can be operated at the first beam power and used to heat the material used to form one or more workpieces. The second working beam deflected by the second deflection unit of the first deflection module and the second working beam deflected by the second deflection unit of the second deflection module can then be operated at the second beam power for laser processing of the one or more workpieces. All working beams, i.e., all deflection units, can operate simultaneously in any case. BRIEF DESCRIPTION OF THE DRAWINGS Fig. Figure 1 shows a perspective view of the interior of a deflection module according to embodiments of the invention. Fig. Figure 2 shows a schematic top view of a deflection module such as the deflection module of Fig. 1 according to some embodiments of the invention. Fig. Figure 3 shows a schematic side view of a deflection module such as the deflection module of Fig. 1 according to some embodiments of the invention. Fig. Figure 4 shows a schematic representation of the working fields and the common overlap area of a deflection module according to some embodiments of the invention. Fig. Figure 5 is a schematic flowchart of an example procedure for laser processing of a workpiece. Fig. Figure 6 shows schematic perspective views of the exterior of a deflection module according to some embodiments of the invention. Fig. Figure 6a shows a perspective view from above and Fig. Figure 6b shows a perspective view from below. Fig. Figure 7 shows a schematic perspective view of the exterior of a modular deflection system according to some embodiments of the invention. Fig. Figure 7a shows a perspective view from above and Fig. Figure 7b shows a perspective view from below. Fig. Figure 8 shows a schematic top view of the interior of a modular deflection system such as the modular deflection system of Fig. 7 according to some embodiments of the invention. Fig. Figure 9 shows a schematic representation of the working fields and the common overlap field of a modular deflection system such as the modular deflection system of Fig. 7 according to some embodiments of the invention. DETAILED DESCRIPTION OF PREFERRED EXECUTION FORMS
[0087] To facilitate understanding of the principles of the invention, reference is now made to a preferred embodiment illustrated in the drawings, and specific terms are used to describe it. It is understood, however, that this is not intended to limit the scope of the invention, and that the invention encompasses any changes and further modifications of the illustrated device and further applications of the inventive principles illustrated therein that a person skilled in the art would normally consider at present or in the future.
[0088] Fig. Figure 1 shows a schematic perspective view of the interior of a deflection module according to some embodiments of the invention, in particular the optical components contained therein. The first deflection module comprises a first deflection unit 10a and a second deflection unit 10b. The first deflection unit 10a comprises a first deflection device 12a, which includes a first movable mirror 12a-1 and a second movable mirror 12a-2. Fig. 2 and Fig. Figure 3 shows a top view and a side view of a deflection module according to embodiments of the invention such as the one in Fig. The deflection module shown in point 1 uses the same reference numerals for the same components. The following description may use the... Fig. 1, Fig. 2 to Fig. 3 can be considered together insofar as they show the same components.
[0089] The first movable mirror 12a-1 is for deflecting a first working beam 50a in a first direction, which is in the Fig. In the embodiment shown in 1, the x-direction corresponds to a pivot about a first axis A1, which is located in the Fig. In the embodiment shown in Figure 1, the first movable mirror 12a-1 of the first deflection unit 10a is arranged at an inclination of approximately 15° to the vertical z-direction. The movement or pivoting of this mirror is driven by a galvanometer motor 14a-1, which is arranged extending along the first axis A1, i.e., with a longitudinal axis corresponding to the maximum dimension of the stepper motor 14a-1 extending along the first axis A1.
[0090] The second movable mirror 12a-2 is designed to reflect the first working beam 50a, after the first working beam 50a has been reflected by the first movable mirror 12a-1, in a second direction, which is in the Fig. In the embodiment shown in 1, a y-direction perpendicular to the x- and z-directions is deflected by pivoting about a second axis A2, which is located in the Fig. In the embodiment shown in Figure 1, the second movable mirror 12a-2 of the first deflection unit 10a is aligned with the x-direction. The movement or pivoting of the second movable mirror 12a-2 of the first deflection unit 10a is driven by a galvanometer motor 14b-2, which is arranged essentially parallel to the second axis A2, i.e., essentially perpendicular to the common mirror symmetry plane M.
[0091] The first movable mirror 12a-1 and the second movable mirror 12a-2 thus form an XY deflection device designed to deflect the first working beam 50a in the x and y directions over a two-dimensional working field 40a. One or more workpieces or raw materials located within the working field 40a can therefore be laser-processed with the first working beam 50a deflected by the first deflection unit 10a.
[0092] The first working beam 50a is generated by a first laser source 28a, which is optically connected to the first deflection unit 10a and / or, in some embodiments, integrated into the first deflection unit 10a. In the embodiment under consideration, the first laser source 28a is configured to generate laser light with a wavelength of 1070 nm, which forms the first working beam 50a.
[0093] After the working beam 50a is generated by the first laser source 28a, it passes through a first focusing device 20a, which is configured to focus, zoom, and collimate the working beam 50a. The focusing device 20a comprises a first movable lens 22a, a second movable lens 24a, and a fixed lens 26a, wherein the movable lenses 22a and 24a can be moved in the z-direction to set a variable focal length of the first focusing device 20a and to zoom and collimate the first working beam 50a, thereby, for example, setting a beam diameter of the first working beam 50a. In other embodiments, the first lens 22a can be a fixed lens.The first focusing device 20a operates as a focusing and zoom unit, which adjusts the focal length of the entire optical system of the first deflection unit 10a so that the first working beam 50a is focused on the first working field 40a at a distance SR to the second movable mirror 12a-2 (cf. . Fig. 3).
[0094] After propagation through the first focusing device 20a, the first working beam 50a is reflected by a first optical element 16a located in the Fig. In the embodiment shown in Figure 1, a dichroic mirror is designed to reflect light in a first wavelength range from 1020 nm to 1080 nm, so that the first working beam 50a is deflected from the z-direction, from which it comes from the first laser source 28a, in the x-direction towards the first deflection device 12a (see Figure 1). Fig. 3, which is one of the perspective views of Fig. 1 corresponding side view in the zx plane).
[0095] In the Fig. 1, Fig. 2 to Fig. In the embodiments shown in Figure 3, the working beam 50a is generated by the first laser source 28a and fed vertically (in the z-direction) into the first deflection unit. The first optical element 16a is therefore arranged in the xz-plane at an angle of 45° to both the z- and x-directions (see Figure 3). Fig. 3) However, other configurations and corresponding arrangements of the first optical element 16a are also possible. In other embodiments, the first working beam 50a can enter the first deflection units 10a in the horizontal x-direction or in a diagonal direction, for example, a diagonal direction in the xz-plane, i.e., a direction with an x-component and a z-component, for example, at an angle of 45°, although other angles are also possible. The first optical element 16a can then be arranged at a corresponding angle to direct the first working beam 50a onto the first deflection device 12a, in particular onto the first movable mirror 12a-1. The same applies to the second deflection unit 10b, which will be described below, with regard to the arrangement of the second laser source 28b and the second optical element 16b.
[0096] The deflection module further comprises a second deflection unit 10b, whose construction, arrangement, and optical components correspond to, or may be identical to, the components of the first deflection unit 10a. For example, the lenses 22b, 24b, and 26b of the second focusing device 20b may be identical to the corresponding lenses 22a, 24a, and 26a of the first focusing device 20a, respectively. Likewise, the second optical element 16b of the second deflection unit 10b may be identical to the corresponding first optical element 16a of the first deflection unit 10a and arranged accordingly to perform the same function. The second focusing device 20b serves as a focusing and zoom unit, adjusting the focal length of the entire optical system of the second deflection unit 10b such that the second working beam 50b is focused onto the second working field 40b at a distance SR from the second movable mirror 12b-2 (see Figure 1). Fig. 3).
[0097] The second deflection unit 10a comprises a second deflection device 12b, which includes a first movable mirror 12b-1 and a second movable mirror 12b-2, which correspond in function and construction to the first movable mirror 12a-1 and the second movable mirror 12a-2 of the first deflection unit 10a. The first movable mirror 12b-1 is configured to scan a second working beam 50b, which is generated by a second laser source 28b that is functionally identical to the first laser source 28a, in the first direction (x-direction) by pivoting about a third axis A3, which is located in the Fig. In the embodiment shown in Figure 1, the first movable mirror 12b-1 of the second deflection unit 10b is arranged parallel to the first axis A1, i.e., also with respect to the vertical z-direction, at an inclination of approximately 15°. The movement or pivoting of the first movable mirror 12b-1 of the second deflection unit 10b is driven by a galvanometer stepper motor 14b-1, which, like the galvanometer motor 14a-1, is arranged along the first axis A3.
[0098] The second movable mirror 12b-2 is designed to scan the second working beam 50b after the second working beam 50b has been reflected by the second optical element 16b and the first movable mirror 12b-1, by pivoting about a fourth axis A4 which is aligned with the second axis A2 in the x-direction (cf. Fig. 2, which shows a top view in the xy-plane, corresponding to the perspective view of Fig. 1 corresponds). The movement or pivoting of the second movable mirror 12a-2 of the first deflection unit 10a is driven by a galvanometer motor 14b-2, which is arranged essentially parallel to the fourth axis A4 (and to the second axis A2) and thus essentially perpendicular to the common mirror symmetry plane M, corresponding to the galvanometer stepper motor 14a-2.
[0099] The first movable mirror 12b-1 and the second movable mirror 12b-2 form an XY deflection device with which the second working beam 50b is scanned in the x and y directions over a two-dimensional working field 40b. One or more workpieces or starting materials located within the working field 40b can thus be laser-processed by the second working beam 50b, which is deflected by the second deflection unit 10b.
[0100] The first deflection unit 10a and the second deflection unit 10b are arranged in a mirror-symmetrical manner with respect to each other and to a common plane of mirror symmetry M, which is in Fig. 1 in the yz-plane, i.e., perpendicular to the x-direction. As shown in the top view of Fig. 2 and in the frontal view of Fig. As can be seen schematically in Figure 3, the beam path followed by the first working beam 50a before it is deflected by the first deflection device 12a, i.e., between the first laser source 28a and the first deflection device 12a, is mirror-symmetrical to the beam path followed by the second working beam 50b before it is deflected by the second deflection device 12b, i.e., between the second laser source 28b and the second deflection device 12b. In the schematic views of the Fig. 1, Fig. 2 to Fig. 3 is the first working ray 50a before it is reflected by the first movable mirror 12a-1, mirror-symmetric to the second working ray 50b before it is reflected by the first movable mirror 12b-1, and aligned with it in the x-direction.
[0101] The portion of the first working beam 50a, which propagates in the z-direction from the first laser source 28a to the first optical element 16a, propagates parallel to the portion of the second working beam 50b, which also propagates in the z-direction from the second laser source 28b to the second optical element 16b. The portion of the first working beam 50a, which propagates from the first optical element 16a to the first movable mirror 12a-1, and the portion of the second working beam 50b, which propagates from the second optical element 16b to the first movable mirror 12b-1, propagate in the x-direction aligned with each other and are directed towards each other, i.e., towards the common mirror symmetry plane M.
[0102] The mirror symmetry between the first deflection unit 10a and the second deflection unit 10b with respect to the common mirror symmetry plane M can be broken along the beam path followed by the first working beam 50a or the second working beam 50b, respectively, from the corresponding deflection device 12a or 12b, especially since the movable mirrors 12a-1 and 12a-2 of the first deflection device 12a may be oriented differently at a certain time than the movable mirrors 12b-1 and 12b-2 of the second deflection device 12b, or may be oriented without corresponding to their mirror-symmetric pivot state, i.e., without corresponding to a mirror image of the movable mirrors 12b-1 and 12b-2 with respect to the common mirror symmetry plane M.However, the first movable mirror 12a-1 and the second movable mirror 12b-1 of the first deflection device 12a are arranged in their 0 pivot positions in a mirror-symmetrical manner with respect to the first movable mirror 12b-1 and the second movable mirror 12b-2 of the second deflection device 12b in their 0 pivot positions.
[0103] Such a mirror-symmetrical arrangement of the first and second deflection units 10a and 10b enables an arrangement of the first deflection device 12a and the second deflection device 12b, in particular the respective second movable mirrors 12a-2 and 12b-2, in which a distance d OCThe distance between the optical center of the second movable mirror 12a-2 and the optical center of the second movable mirror 12b-2 is reduced to a minimum. The second movable mirrors 12a-2 and 12b-2 are arranged very close to each other and separated in the x-direction by a small distance d. Consequently, the first working area 40a of the first deflection unit 10a and the second working area 40b of the second deflection unit 10b overlap at least in a partial area and form a common overlap area 42. The common overlap area 42 belongs to both the first working area 40a and the second working area 40b.
[0104] In the in the Fig. 1, Fig. 2 to Fig. In the 3 illustrated embodiments, the movable mirrors 12a-1, 12a-2, 12b-1 and 12b-2 all have a polygonal shape, designed to form a corresponding working beam with a 1 / e 2-Diameters of up to 30 mm are reflected. The first and second working beams 50a and 50b have a Gaussian-distributed intensity profile in their cross-sections and strike the first mirror 12a-1 of the first deflection device 12a and the first mirror 12b-1 of the second deflection device 12b, respectively, with a first 1 / e 2 - Beam diameter of 20 mm. The first mirrors 12a-1 and 12b-1 are designed to have an aperture equal to 1.5 times the aforementioned 1 / e 2 - beam diameter corresponds to an aperture of 30 mm, so that they can each reflect approximately 99.5% of the light from the first and second working beams 50a and 50b, respectively. The optical centers of the second movable mirrors 12a-2 and 12b-2 are separated in the x-direction by a distance d. OC = 65 mm apart and the edges of the second movable mirrors 12a-2 and 12b-2 are separated in the x-direction by a distance d = 5 mm apart.
[0105] As in Fig. As can be seen in Figure 2, each of the second movable mirrors 12a-2 and 12b-2 is separated in the y-direction from the corresponding first movable mirror 12a-1 and 12b-1, respectively. However, this distance has no influence on the distance d between the second movable mirrors 12a-2 and 12b-2.
[0106] The mirror-symmetrical and aligned arrangement of the second movable mirrors 12a-2 and 12b-2 makes it possible to determine the distance d OZ to minimize the distance between the optical centers of the second movable mirrors 12a-2 and 12b-b and thus increase the size of the common overlap area 42 without having to increase the distance between each of the second movable mirrors 12a-2 and 12b-2 and the plane on which the first working field 40a and the second working field 40b (and thus the common overlap area 42) lie, i.e. without having to increase the deflection radius.
[0107] As in Fig. Figure 4, which shows a schematic view of the first work area 40a and the second work area 40b in the xy-plane, shows that each of the first and second work areas 40a and 40b has a square shape with a side length L. A = L B = 500 mm, covering an area of 500 mm x 500 mm. The first work area 40a and the second work area 40b are aligned with each other in the y-direction: In the Fig. In the view shown, the left edges of the first and second work areas 40a and 40b are aligned with each other in the y-direction, as are the corresponding right edges. Therefore, the first and second work areas 40a and 40b have a 100% overlap in the y-direction. The first work area 40a and the second work area 40b overlap in the y-direction by a distance of 500 mm. In the x-direction, the first and second work areas 40a and 40b partially overlap (81% overlap) over a distance L. C= 435 mm. The common overlap area 42 therefore covers an area of 500 mm x 435 mm.
[0108] Such a large overlap of the first and second working fields 40a and 40b is compatible with a rather small deflection radius SR thanks to the mirror-symmetric and aligned arrangement of the first and second deflection units 10a and 10b, in particular the second movable mirrors 12a-2 and 12b-2 (cf. Fig. 3) In the Fig. 1, Fig. 2 to Fig. In the 3 considered embodiments, the deflection radius SR = 620 mm.
[0109] The galvanometer motors 14a-2 and 14b-2 for pivoting the second movable mirrors 12a-2 and 12b-2, respectively, are arranged on opposite sides of the corresponding second movable mirror 12a-2, 12b-2: As shown in Fig. 1 and Fig. As can be seen in Figure 2, the second movable mirror 12a-2 is arranged between the common mirror symmetry plane M and the stepper motor 14a-2. As shown in Figure 2, the second movable mirror 12a-2 is arranged between the common mirror symmetry plane M and the stepper motor 14a-2. Fig. As can be seen in the xy-plane, the galvanometer motor 14a-2 is arranged to the left of the second movable mirror 12a-2. Likewise, the second movable mirror 12b-2 is arranged between the common mirror symmetry plane M and the galvanometer motor 14b-2, so that, as shown in Figure 2, the galvanometer motor 14a-2 is arranged to the left of the second movable mirror 12a-2. Fig. As can be seen in the xy-plane, the galvanometer motor 14b-2 is arranged to the right of the second movable mirror 12b-2. This arrangement, in which the galvanometer motors extend in the x-direction perpendicular to the common mirror symmetry plane M, saves space and allows for a smaller distance between the second movable mirrors 12a-2 and 12b-2, thus avoiding interference or collision between the stepper motors 14a-2 and 14b-2 and other components of the deflection module, as well as between the second movable mirrors 12a-2 and 12b-2.
[0110] In the schematic representation of Fig. Figure 2 does not include the galvanometer motors assigned to the first movable mirrors 12a-1 and 12b-1 for illustrative purposes. For the same reason, the schematic view of Fig. 3 none of the galvanometer motors of the deflection module and shows only the first and second deflection device as a schematic superposition of the corresponding movable mirrors 12a-1, 12a-2 and 12b-1, 12b-2 respectively.
[0111] As in Fig. As shown in Figure 3, each of the first and second deflection units 10a and 10b also defines a corresponding detection beam path for a first detection beam 52a and a second detection beam 52b, respectively. The optical elements 16a and 16be are not only reflective in the aforementioned wavelength range between 1000 nm and 1100 nm, but also have a high transmittance for wavelengths below 1000 nm and above 1100 nm.This results in reflected light, which arises in the working fields, for example, from the reflection of the illumination light or the light of the first and / or second working beam 50a, 50b, and is reflected back by the deflection devices 12a and 12b, being transmitted by the respective optical element 16a and 16b, so that the corresponding detection beams 52a and 52b propagate from the respective working field 40a and 40b to a respective detection device 70a, 70b, which is designed to receive and detect the detection beams 52a and 52b for monitoring the laser processing by the corresponding deflection unit 10a or 10b. In the present embodiment, the detection devices 70a and 70b each comprise a camera. Furthermore, the first and second deflection units 10a and 10b each comprise a set of movable lenses 72a, 72b and 72b respectively.fixed lenses 74a, 74b for focusing the respective detection beam 52a and 52b onto the corresponding detection device 70a, 70b for each position on the working fields 40a, 40b, from which the reflected light could reach the detection devices 70a and 70b depending on the settings of the corresponding deflection devices 12a and 12b.
[0112] Fig. Figure 5 is a flowchart of an exemplary procedure 200 for laser processing of one or more workpieces using a deflection module, as described in the Fig. 1, Fig. 2 to Fig. 3 above. The workpiece can be formed from a base material such as metal powder by laser processing successive layers of the base material within the common overlap area 42 using the first deflection unit 10a and the second deflection unit 10b of the deflection unit.
[0113] In method 200, the first deflection unit 10a of the deflection module is used to scan the working beam 50a, which is a laser beam with a first power density of 4 MW / cm². 2 is generated, and the second deflection unit 10b of the deflection module for scanning the working beam 50b, which is a laser beam with a second power density of 40 MW / cm². 2 The first working beam 50a and the second working beam 50b can be generated by identical laser sources with the same beam power. The higher power density of the second working beam is achieved by the fact that the second working beam 50b has a smaller spot size than the first working beam 50a.
[0114] The first working beam 50a is used to heat the base material, and the second working beam 50b is then used for laser processing of the base material in areas where the base material has already been heated by the first working beam 50a. The first and second working beams 50a and 50b can operate simultaneously, so that the first working beam 50a heats further areas of the base material while the second working beam 50b laser processes areas of the base material that have already been heated by the first working beam 50a.
[0115] For each layer of the base material to be processed with the laser, the first working beam 50a is initially used at specific locations on the base material (202) to heat the base material. Subsequently, at 204, the second working beam 50b is used at the same locations on the base material to laser process the heated base material.
[0116] In other embodiments (not shown), the first working beam 50a can also be used to slow down the cooling of points on the base material that have previously been laser-processed by the second working beam 50b.
[0117] If several deflection modules are combined for cooperative operation (see description of the Fig. 7, Fig. 8 to Fig. 9 below), more than two working beams are available, whereby more than one working beam, e.g. two, in 202 can be used to heat and / or cool the base material and more than one working beam, e.g. two, in 204 can be used to laser processing points of the base material that has already been heated or cooled by the other working beams.
[0118] Fig. Figure 6 schematically shows two different perspective external views of a deflection module according to embodiments of the invention, comprising a first deflection unit 10a and a second deflection unit 10b, as they are used in the embodiments of the Fig. 1, Fig. 2 to Fig. 3 are described. As in Fig. As can be seen in Figure 6, the deflection module comprises a housing 60. All components listed in the diagram are housed within the housing 60. Fig. 1, Fig. 2 to Fig. 3 optical components described, with the exception of laser sources 28a and 28b in the Fig. 1, Fig. 2 to Fig. The arrangement shown in Figure 3 is housed, wherein the longitudinal direction of the housing 60, i.e., the direction in which the housing 60 extends the longest, corresponds to the x-direction. In the arrangement shown in Fig. In the embodiment shown in Figure 6, the housing 60 comprises an optical inlet 68a, 68b in the form of an optical connection for receiving a laser source such as the one shown in the Fig. 1, Fig. 2 to Fig. The laser sources 28a and 28b described in Figure 3 are arranged in a diagonal position in the xz-plane when coupled to the optical inlet 68a, 68b, forming an angle of 30° with respect to both the z- and x-axes. Fig. In the embodiments shown in section 6, the laser light generated by the laser sources enters the deflection module in such a diagonal direction.
[0119] The housing 60 is water and dustproof and meets the IP64 protection class according to the International Protection Rating, so that the inside of the housing 60 is isolated from the external environment by the sealing effect of the housing 60.
[0120] The housing 60 comprises a first transparent window 62a and a second transparent window 62b, each formed by glass plates arranged at the bottom of the housing 60, as shown in Fig. 6b shown. The first transparent window 62a is arranged below the second movable mirror 12a-2 of the first deflection device 12a of the first deflection module 10a, in the xy-plane (cf. Fig. 1, Fig. 2 to Fig. 3) aligned with the second movable mirror 12a-2, at a distance in the z-direction of approximately 55 mm from the second movable mirror 12a-2, so that the first working beam 50a can pass through the first transparent window 62a for any target point of the first working field 40a, i.e., for any deflection setting of the first deflection device 12a. Likewise, the second transparent window 62b is arranged below the second movable mirror 12b-2 of the second deflection device 12b of the second deflection module 10b, aligned with the second movable mirror 12b-2 in the xy-plane (see Figure 1). Fig. 1, Fig. 2 to Fig. 3), arranged at a distance in the z-direction of about 55 mm from the second movable mirror 12b-2, so that the second working beam 50b can be passed through the second transparent window 62b for any target point of the second working field 40b, i.e. for any deflection setting of the second deflection device 12b.
[0121] The first transparent window 62a and the second transparent window 62b are arranged side by side so that they have a common border 65. In the Fig. In the embodiment shown in Figure 6, the first transparent window 62a and the second transparent window 62b are formed by independent glass plates. In other embodiments, however, the first transparent window 62a and the second transparent window 62b can be joined together, and a single glass plate can cover both the first and the second transparent windows 62a and 62b.
[0122] As in Fig. As can be seen in Figure 6, the first transparent window 62a and the second transparent window 62b are arranged next to a side wall 63 of the housing 60, instead of being centered in the middle of the lower part of the housing or in the y-direction. In other words, the first and second transparent windows are not equidistant from the side wall 63 of the housing and from the opposite side wall of the housing. As shown in Fig. As shown in Figure 7, this allows for two deflection modules 102 and 104, such as those in Figure 7. Fig. 1, Fig. 2 to Fig. The deflection modules shown in Figures 3 (interior views) and 6 (exterior view) are connected to form a modular deflection system with a minimum distance between the transparent windows 62a and 62b of a first housing 60a of a first deflection module and the corresponding transparent windows 62c and 62d of a second housing 60b of a second deflection module. Fig. 7a and Fig. Figure 7b shows perspective views from different angles of a first deflection module 102 and a second deflection module 104, which are detachably attached to each other and form a modular deflection system.
[0123] As in Fig. As can be seen in Figure 7b, the transparent windows 62a and 62b of the first deflection module 102 and the transparent windows 62c and 62d of the second deflection module 104 are arranged offset from a central position with respect to the longitudinal axis of their respective deflection modules, without being equidistant with respect to opposite side walls of their respective housings 60a and 60b, so that the transparent windows 62a and 62b of the first housing 60a adjoin the transparent windows 62c and 62d of the second housing 60b when the first and second deflection modules 102, 104 are attached to each other. The housings 60a and 60b include a fastening mechanism (not shown) for detachably or removably attaching the first and second deflection modules 102, 104 to each other.
[0124] Fig. Figure 8 shows a schematic front view of the interior of the building. Fig. 7 modular deflection system shown, when the first deflection module 102 and the second deflection module 104 are attached to each other. The first and second deflection modules 102 and 104 each correspond to a deflection module like the one in the Fig. 1, Fig. 2 to Fig. The deflection module described in section 3 consists of the same components in the corresponding arrangement. Thus, it corresponds to... Fig. 8 a doubling of the schematic top view of Fig. 2. The first deflection module 102 and the second deflection module 104 are mirror-symmetric to each other and to another plane of mirror symmetry O, which is located in Fig. As indicated in point 8, it is arranged.
[0125] Due to the symmetrical arrangement of the first and second deflection modules 102 and 104, wherein the first deflection module 102 has a first common mirror symmetry plane M1 corresponding to the plane M in the Fig. 1, Fig. 2 to Fig. 3 and the second deflection module 104 a second common mirror symmetry plane M2 corresponding to the plane M in the Fig. 1, Fig. 2 to Fig. 3 defined, and due to the arrangement of the respective second movable mirrors 12a-2, 12b-2, 12c-2 and 12d-2, which are arranged adjacent to a side edge of the respective deflection module (according to the in Fig. In the arrangement of the transparent windows 62a-62d described in Figure 7, the distance between each pair of the second movable mirrors 12a-2, 12b-2, 12c-2, and 12d-2 is reduced to a minimum. The distance between the second movable mirrors 12a-2 and 12b-2 of the first deflection module 102 and between the second movable mirrors 12c-2 and 12d-2 of the second deflection module 104, as well as the distances between their respective optical centers, correspond to the distances d, d'. OC , which are for the Fig. 1, Fig. 2 to Fig. 3 were described.
[0126] Furthermore, the distance d' between the second movable mirror 12a-2 of the first deflection device 12a of the first deflection module 102 and the second movable mirror 12c-2 of the first deflection device 12c of the second deflection module 104, and between the second movable mirror 12b-2 of the second deflection device 12b of the first deflection module 102 and the second movable mirror 12d-2 of the second deflection device 12d of the second deflection module 104, is approximately 10 mm. The distance d' OCThe distance between the optical center of the second movable mirror 12a-2 of the first deflection device 12a of the first deflection module 102 and the optical center of the second movable mirror 12c-2 of the first deflection device 12c of the second deflection module 104, and between the optical center of the second movable mirror 12b-2 of the second deflection device 12b of the first deflection module 102 and the optical center of the second movable mirror 12d-2 of the second deflection device 12d of the second deflection module 104, is approximately 65 mm.
[0127] Consequently, the size of a common overlap field 44, in which the working field 40a of the first deflection unit 10a of the first deflection module 102, the working field 40b of the second deflection unit 10b of the first deflection module 102, the working field 40c of the first deflection unit 10c of the second deflection module 104 and the working field 40d of the second deflection unit 10d of the second deflection module 104 overlap, can be as shown in Fig. Figure 9 shows that the deflection radius can be increased for a given radius.
[0128] In the Fig.In the embodiment shown in Figure 9, each of the working fields 40a, 40b, 40c, and 40d is a square field with an area of 500 mm x 500 mm. The first and second working fields 40a and 40b of the first deflection module 102 are aligned with each other in a first overlap direction (the x-direction). The first and second working fields 40c and 40d of the second deflection module 104 are also aligned with each other in the first overlap direction (x-direction). The first and second working fields 40a and 40b of the first deflection module 102 and the first and second working fields 40c and 40d of the second deflection module 104 overlap by 87% in the first overlap direction, i.e., over a length of 435 mm. Furthermore, the first working fields 40a and 40c and the second working fields 40b and 40d overlap in a second overlap direction (the y-direction) by 87%, i.e. over a length of 435 mm.Thus, the common overlap field 44 covers an area of 435 mm x 435 mm, while the deflection radius between each of the second movable mirrors 12a-2, 12b-2, 12c-2 and 12d-2 (in their respective 0 pivot positions) and the plane of the working fields 40a, 40b, 40c and 40d is 620 mm.
[0129] Although preferred exemplary embodiments are shown and described in detail in the drawings and the preceding description, these should be considered purely exemplary and not as limiting the invention. It is pointed out in this context that only the preferred exemplary embodiments are shown and specified, and that all variations and modifications that are currently or may become in the future within the scope of protection of the invention, as defined in the claims, should be protected. QUOTES INCLUDED IN THE DESCRIPTION
[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature
[0000] US 2019 / 0283332 A1
[0008] US 2019 / 310463 A1
[0009] US 2017 / 173883 A1
[0010] EP 3 532 238 A1 [0062, 0063]
Claims
[1] Deflection module comprising the following: a first deflection unit (10a) comprising a first deflection device (12a) configured to deflect a first working beam (50a) over a first working field (40a), wherein the first deflection device (12a) has the following: a first movable mirror (12a-1) for deflecting the first working beam (50a) in a first direction (x) by pivoting about a first axis (z); and a second movable mirror (12a-2) for deflecting the first working beam (50a) in a second direction (y) by pivoting about a second axis (x); a second deflection unit (10b) comprising a second deflection device (12b) configured to deflect a second working beam (50b) over a second working field (40b); wherein the second deflection device (12b) comprises: a first movable mirror (12b-1) for deflecting the second working beam (50b) in the first direction (x) by pivoting about a third axis (z); and a second movable mirror (12b-2) for deflecting the second working beam (50b) in the second direction (y) by pivoting about a fourth axis (z); wherein the second movable mirror (12a-2) of the first deflecting device (12a) and the second movable mirror (12b-2) of the second deflection device (12b) are arranged symmetrically to each other and to a common plane of symmetry (M); and wherein the first work area (40a) and the second work area (40b) overlap in a common overlap area (42); wherein the first and second working areas (40a, 40b) each cover an area of 100 mm x 100 mm to 1000 mm x 1000 mm; wherein the second movable mirror (12a-2) of the first deflection device (12a) is arranged along a beam path of the first working beam (50a) in the direction of the first working field (40a) after the first movable mirror (12a-1) of the first deflection device (12a), wherein the second movable mirror (12b-2) of the second deflection device (12b) is arranged along a beam path of the second working beam (50b) in the direction of the second working field (40b) after the first movable mirror (12b-1) of the second deflection device (12b), wherein the height (SR) of the second movable mirror (12a-2) of the first deflection device (12a) above the first working field (40a) and / or the height (SR) of the second movable mirror (12b-2) of the second deflection device (12b) above the second working field (40b) does not exceed 800 mm; wherein the first deflection unit (10a) and / or the second deflection unit (10b) further comprises an optical element (16a; 16b) for at least partially reflecting working light in a first wavelength range of the first or the second working beam (50b), wherein the respective deflection device (12a, 12b) is arranged in the beam path of the corresponding working beam (50a, 50b) between the corresponding working field (40a, 40b) and the corresponding optical element (16a, 16b), so that the corresponding working beam (50a, 50b) propagates to the corresponding deflection device (40a, 40b) and is reflected at the corresponding optical element (16a, 16b); wherein the first wavelength range of the first or second working beam (50b) covers 1000 nm to 1100 nm; and wherein a distance (dOC) between an optical center of the second movable mirror (12a-2) of the first deflection device (12a) and an optical center of the second movable mirror (12b-2) of the second deflection device (12b) is not more than 120 mm. [2] Deflection module according to claim 1, wherein the first deflection device (12a) further comprises a first galvanometer motor (14a-2) for pivoting the second movable mirror (12a-2) of the first deflection device (12a); wherein the second deflection device (12b) further comprises a second galvanometer motor (14b-2) for pivoting the second movable mirror (12b-2) of the second deflection device (12b); and wherein the first galvanometer motor (14a-2) and the second galvanometer motor (14b-2) are arranged on opposite sides of the respective second movable mirror with respect to the common mirror symmetry plane (M), so that the first galvanometer motor (14a-2) and the second galvanometer motor (14b-2) are arranged in a mirror-symmetric arrangement with respect to each other and to the common mirror symmetry plane (M). [3] Deflection module according to claim 1 or 2, wherein the first working beam (50a) propagates in a first direction of incidence (x) perpendicular to the common mirror symmetry plane (M) onto the first deflection device (12a), and wherein the second working beam (50b) propagates in a second direction of incidence (x) perpendicular to the common mirror symmetry plane (M) onto the second deflection device (12b), wherein the first direction of incidence is aligned with and opposite to the second direction of incidence. [4] Deflection module according to one of the preceding claims, wherein the first deflection unit (10a) and the second deflection unit (10b) are arranged in a mirror-symmetric manner with respect to the common plane of mirror symmetry (M), such that a beam path of the first working beam (50a) before it is deflected by the first deflection device (12a) and a beam path of the second working beam (50b) before it is deflected by the second deflection device (12b) are mirror-symmetric to each other and to the common plane of mirror symmetry (M). [5] Deflection unit according to one of the preceding claims, wherein a beam path of the first working beam (50a), before it is deflected by the first deflection device (12a), is aligned with a beam path of the second working beam (50b), before it is deflected by the first deflection device (12a), in a direction perpendicular to the common mirror symmetry plane (M). [6] Deflection module according to one of the preceding claims, wherein a distance (d) between the second movable mirror (12a-2) of the first deflection device (12a) and the second movable mirror (12b-2) of the second deflection device (12b) is not more than 1 / 3 of a diameter (D1, D2) of the second movable mirror of the first deflection device (12a) and / or of the second movable mirror of the second deflection device (12b), preferably not more than 1 / 4 thereof, particularly preferably not more than 1 / 5 or 1 / 6 thereof. [7] Deflection module according to one of the preceding claims, wherein a distance (dOC) between an optical center of the second movable mirror (12a-2) of the first deflection device (12a) and an optical center of the second movable mirror (12b-2) of the second deflection device (12b) is not more than 4 times an aperture of the first movable mirror of the first deflection device (12a) and / or the first movable mirror of the second deflection device (12b), preferably not more than 3 times, particularly preferably not more than 2.5 times or 2 times. [8] Deflection module according to claim 7, wherein the first working beam (50a) strikes the first deflection device (12a) with a first 1 / e² beam diameter, and wherein the second working beam (50b) strikes the second deflection device (12b) with a second 1 / e² beam diameter, the second beam diameter preferably being equal to the first beam diameter, wherein the aperture of the first movable mirror of the first deflection device (12a) and / or the first movable mirror of the second deflection device (12b) is at least 1.1 times, preferably at least 1.3 times, particularly preferably at least 1.5 times the first 1 / e² 2 - beam diameter or of the second 1 / e 2 - corresponds to the ray diameter. [9] Deflection module according to one of the preceding claims, wherein a distance (dOC) between an optical center of the second movable mirror (12a-2) of the first deflection device (12a) and an optical center of the second movable mirror (12b-2) of the second deflection device (12b) is not more than 80 mm, preferably not more than 60 mm. [10] Deflection module according to one of the preceding claims, wherein the first working field and the second working field are aligned to each other in a direction parallel to the common mirror symmetry plane, and wherein the common overlap area (42) has an extent in an overlap direction perpendicular to the common mirror symmetry plane which corresponds to at least 75%, preferably at least 80%, particularly preferably at least 90% of the extent covered by the first and / or the second working field in the overlap direction. [11] Deflection module according to one of the preceding claims, wherein the height (SR) of the second movable mirror (12a-2) of the first deflection device (12a) above the first working field (40a) and / or the height (SR) of the second movable mirror (12b-2) of the second deflection device (12b) above the second working field (40b) is not more than 600 mm, preferably not more than 400 mm. [12] Deflection module according to one of the preceding claims, further comprising a housing (60) wherein the first deflection unit (10a) and the second deflection unit (10b) are enclosed in the housing (60), wherein the housing is preferably dustproof and / or waterproof. [13] Deflection module according to claim 11, wherein the housing (60) has a first transparent window (62a) configured to allow the first working beam (50a) propagating from the first deflection device (12a) to the first working field (40a) to pass through, and a second transparent window (62b) configured to allow the second working beam (50b) propagating from the second deflection device (12b) to the second working field (40b) to pass through, wherein the first transparent window (62a) and / or the second transparent window (62b) preferably comprises a glass plate. [14] Deflection module according to claim 13, wherein the first transparent window (62a) and the second transparent window (62b) are adjacent to each other, and / or wherein the first transparent window (62a) and the second transparent window (62b) are adjacent to the same side wall (63) of the housing (60), and / or wherein the first transparent window (62a) and the second transparent window (62b) are connected to each other. [15] Deflection module according to one of the preceding claims, wherein the optical element (16a, 16b) further transmits detection light in a second wavelength range at least partially, wherein the respective deflection unit (10a, 10b) preferably defines a detection beam path in which a detection beam (52a, 52b) in the second wavelength range propagates from the corresponding working field (40a, 40b) to a corresponding detection device (70a, 70b), wherein the detection beam (52a, 52b) preferably propagates from the corresponding working field (40a, 40b) to the corresponding detection window and is thereby reflected by the corresponding deflection device (12a, 12b) and transmitted by the corresponding optical element (16a, 16b). [16] Deflection module according to one of the preceding claims, wherein the first deflection unit (10a) and / or the second deflection unit (10b) further comprises a focusing device (20a, 20b) for focusing, zooming and / or collimating the respective working beam (50a, 50b), wherein the focusing device (20a, 20b) has a variable focal length, wherein the focusing device (20a, 20b) preferably comprises a first fixed lens (26a, 26b), a first movable lens (24a, 24b) and a further fixed or movable lens (22a, 22b). [17] Deflection module according to one of the preceding claims, wherein the first and second working fields (40a, 40b) each cover an area of 300 mm x 300 mm to 700 mm x 700 mm, preferably 400 mm x 400 mm to 600 mm x 600 mm [18] Deflection module according to one of the preceding claims, wherein a distance (d) between the second movable mirror (12a-2) of the first deflection device (12a) and the second movable mirror (12b-2) of the second deflection device (12b) is not more than 50 mm, preferably not more than 30 mm and more preferably not more than 10 mm. [19] Modular deflection system (100) comprising a first deflection module (102) according to one of the preceding claims and a second deflection module (104) according to one of the preceding claims, wherein the first deflection module (102) and the second deflection module (104) can be mounted together; wherein the common overlap area (42) of the first deflection module (102) and the common overlap area (42) of the second deflection module (104) overlap and thereby form a common overlap field (44) when the first deflection module (102) and the second deflection module (104) are mounted next to each other. [20] Modular deflection system according to claim 19, wherein the first deflection module (102) and the second deflection module (104) are mirror-symmetric to each other when the first deflection module (102) and the second deflection module (104) are mounted together. [21] Modular deflection system according to claim 19 or 20, wherein a distance (d') between an optical center of the second movable mirror (12a-2) of the first deflection device (12a) of the first deflection module (102) and an optical center of the second movable mirror (12c-2, 12d-2) of the first or second deflection device (12c, 12d) of the second deflection module (104) is not more than 4 times an aperture of the first movable mirror (12a-1) of the first deflection device (12a) of the first deflection module (102), preferably not more than 3 times, particularly preferably not more than 2.5 times or 2 times. [22] Modular deflection system according to one of claims 19 to 21, wherein a distance (d'OC) between an optical center of the second movable mirror (12a-2) of the first deflection device (12a) of the first deflection module (102) and an optical center of the second movable mirror (12c-2, 12d-2) of the first or second deflection device (12c, 12d) of the second deflection module (104) is not more than 120 mm, preferably not more than 80 mm, particularly preferably not more than 60 mm. [23] Modular deflection system according to any one of claims 19 to 22, wherein the first deflection module (102) has a first housing (60a), wherein the first deflection unit (10a) and the second deflection unit (10b) of the first deflection module (102) are enclosed in the first housing (60a), wherein the first housing (60a) is preferably dustproof and / or waterproof; and wherein the second deflection module (104) has a second housing (60b), wherein the first deflection unit (10a) and the second deflection unit (10b) of the second deflection module (104) are enclosed in the second housing (60b), wherein the second housing (60b) is preferably dustproof and / or waterproof; wherein the first housing (60a) and the second housing (60b) can be mounted together such that the first housing (60a) and the second housing (60b) are arranged adjacent to each other when the first deflection module (102) and the second deflection module (104) are mounted together. [24] Modular deflection system according to claim 23, wherein the first housing (60a) has a first transparent window (62a) through which the respective first working beam (50a) propagates from the first deflection device (12a) of the first deflection module (102) to the respective first working field (40a), and has a second transparent window (62b) through which the respective second working beam (50b) propagates from the second deflection device (12b) of the first deflection module (102) to the respective second working field (40b), wherein the second housing (60b) has a third transparent window (62c) through which the respective first working beam (50c) propagates from the first deflection device (12c) of the second deflection module (104) to the respective first working field (40c), and has a fourth transparent window (62d) through which the respective second working beam (50d) propagates from the second deflection device (12d) of the second deflection module (104) to the respective second working field (40d), wherein the first transparent window (62a), the second transparent window (62b), the third transparent window (62c) and / or the fourth transparent window (62d) are arranged adjacent to each other when the first deflection module and the second deflection module are mounted next to each other. [25] Modular deflection system according to any one of claims 19 to 24, wherein the first and second working fields (40a, 40b) of the first deflection module (102) are aligned with each other in a first overlap direction and the first and second working fields (40c, 40d) of the second deflection module (104) are aligned with each other in this first overlap direction, wherein the first overlap direction preferably runs parallel to the common plane of mirror symmetry of the first and second deflection modules (102, 104), wherein the first working field (40a) of the first deflection module (102) is aligned with the first and second working fields (40c, 40d) of the second deflection module (104) in a second overlap direction perpendicular to the first overlap direction, and wherein the second working field (40b) of the first deflection module (102) is aligned with the second and second working fields (40c, 40d) of the second deflection module (104) in a second overlap direction perpendicular to the first overlap direction.the first working field (40d, 40c) of the second deflection module (104) is aligned in the second overlap direction, wherein in the first overlap direction and in the second overlap direction the common overlap field (44) has an extent that corresponds to at least 75%, preferably at least 80%, particularly preferably at least 90% of the extent that is covered by the first and / or second working field (40a, 40b, 40c, 40d) of the first and / or second deflection module (102, 104) in the corresponding overlap direction.
Citation Information
Patent Citations
Deflection unit comprising two windows, an optical element and an XY-deflection device
EP3532238A1
Additive manufacturing method using tilted scanners
US20170173883A1
Localising sensor data collected during additive manufacturing
US20190283332A1
deflector
US20190310463A1