Apparatus for additive manufacturing of three-dimensional objects

Abstract

The present invention relates to an apparatus (1) for additively manufacturing a three-dimensional object (2) by selectively irradiating and curing layers of building material (3) sequentially, the building material (3) being curable by an energy beam (4), wherein a measuring unit (5) is provided, the measuring unit (5) being configured to generate information relating to the collimated portion (6) of the energy beam (4) and information relating to the focused portion (7) of the energy beam (4).

Description

[0001] This application is a divisional application of patent application No. 201711238412.9 filed on November 30, 2017, entitled "Apparatus for Additively Manufacturing Three-Dimensional Objects". Technical Field

[0002] The present invention relates to an apparatus for additively manufacturing three-dimensional objects by selectively irradiating and curing layers of building materials that can be cured by means of an energy beam. Background Technology

[0003] Devices that use energy beams to selectively irradiate layers of building materials are well known in the prior art, whereby the building materials are cured by the irradiation of the energy beam. To ensure or maintain constant process quality, it is necessary to monitor various process parameters, such as the power of the energy beam or the energy consumed by the energy beam in the building material.

[0004] For example, due to variations in process temperature, such as the temperature of at least one component of the equipment, the focal position of the energy beam may shift. This temperature-induced shift in focal position needs to be corrected; otherwise, irradiating the building material with a defocused energy beam will result in deviations in the object. Therefore, it is preferable to monitor and control various process parameters to ensure constant process quality. Summary of the Invention

[0005] Therefore, the object of the present invention is to provide an apparatus for improving the control of process parameters.

[0006] The objective is inventively achieved by the device according to claim 1. Advantageous embodiments of the invention are provided by the dependent claims.

[0007] The apparatus described herein is for additively manufacturing three-dimensional objects, such as technical components, by sequentially and selectively irradiating and solidifying layers of powdered building material (“building material”), which can be solidified by means of an energy beam. The building material can be metal, ceramic, or polymer powder. The energy beam can be a laser beam or an electron beam. The apparatus can be, for example, a selective laser sintering apparatus, a selective laser melting apparatus, or a selective electron beam melting apparatus.

[0008] The device includes multiple functional units used during its operation. Exemplary functional units are a process chamber, an irradiation device configured to selectively irradiate a layer of building material arranged in the process chamber using at least one energy beam, and a flow generating device configured to generate a flow of gaseous fluid that flows through the process chamber at least partially with given flow characteristics, such as a given flow profile, flow velocity, etc.

[0009] The present invention is based on the idea of ​​providing a measurement unit comprising at least one measuring device configured to generate information relating to the collimated portion of an energy beam and information relating to the focused portion of the energy beam. Therefore, multiple process parameters can be monitored because information is generated not only relating to the focused portion of the energy beam—e.g., the portion of the energy beam between the focusing optics and the building plane—but also relating to the collimated portion of the energy beam—e.g., the portion of the energy beam between the collimating optics and the focusing optics. Thus, a shift in the focal position of the energy beam or a shift in the focal length of at least one optical device can be determined. This, for example, allows adjustment of at least one process parameter to at least partially compensate for the shift in the focal position or the shift in the focal length.

[0010] Therefore, the present invention can ensure constant process quality because, for example, the focal position of the energy beam can be kept constant, thereby allowing a constant energy input to the building materials that must be irradiated.

[0011] According to an advantageous embodiment, the device includes:

[0012] A first beam splitter is located between a collimating optics and a focusing optics, wherein a first beam path extends from the collimating optics through the focusing optics to the building plane, a second beam path extends from the collimating optics to the first measuring device, and a third beam path extends from the building plane and / or from the surface between the building plane and the focusing optics through the focusing optics to the second measuring device, wherein...

[0013] - The first measuring device is configured to generate information related to the collimated portion of the energy beam, and

[0014] - The second measuring device is configured to generate information related to radiation emitted from the area of ​​the construction plane and / or to generate information related to the focused portion of the energy beam.

[0015] Therefore, a first beam splitter is used to split the energy beam exiting the collimating optics into a first beam path and a second beam path. The first beam path extends from the collimating optics, through the focusing optics, to the construction plane to irradiate the construction material. The second beam path branches off from the energy beam and extends from the collimating optics to the first measuring device. Furthermore, a third beam path extending from the construction plane and / or from the surface between the construction plane and the focusing optics is guided to the second measuring device via the first beam splitter. This embodiment allows for monitoring of various portions of the energy beam, wherein the collimated portion of the energy beam between the collimating optics and the focusing optics, and the focused portion between the focusing optics and the construction plane, can be evaluated, as can radiation emitted from at least one region of the construction plane and / or from the surface between the focusing optics and the construction plane.

[0016] As used within the scope of this application, the term "emission" or "emitted" refers to radiation that is reflected or generated or similarly formed, wherein the radiation is emitted from a corresponding object or surface. Thus, "emission" is not limited to the generation of radiation with respect to a beam source, but can also be understood as the reflection of radiation at a surface or (thermal) radiation emitted by an object at a defined temperature.

[0017] According to another advantageous embodiment, the first measuring device includes a second beam splitter configured to split a second energy beam traveling along a second beam path into two sub-parts, and / or the second measuring device includes a second beam splitter configured to split a third energy beam traveling along a third beam path into two sub-parts.

[0018] By splitting the second energy beam traveling along the second beam path into two sub-parts and / or splitting the third energy beam traveling along the third beam path into two sub-parts, it is possible to determine or measure whether the individual energy beams are collimated. In other words, the angle at which the light from a single energy beam reaches the detector assigned to the corresponding measuring device can be detected. Therefore, the diameter of the corresponding energy beam is measured at two different positions along the corresponding beam path traveling along the energy beam. By comparing the two diameters measured at the two different positions, information related to the collimation state of the energy beams can be generated.

[0019] Therefore, a single detector or two detectors can be used, wherein the two sub-sections are imaged sequentially on the detector, for example using a shutter unit configured to disable one sub-section, thereby allowing the measurement of the other sub-section of the energy beam, and vice versa. For example, a single detector can move between at least two measurement positions, where the diameter of the corresponding energy beam is measured at both positions and subsequently compared to generate information related to the collimation state of the corresponding energy beam. Thus, the optical path lengths of the two sub-sections traveling to different measurement positions can be varied.

[0020] The device can be further improved, with the first measuring device and / or the second measuring device including two optical sensors, wherein the first sub-part is measured via the first optical sensor and the second sub-part is measured via the second optical sensor.

[0021] According to this embodiment, the energy beam divided into two sub-sections is measured by different optical sensors positioned at different locations, i.e., at different distances from the second beam splitter. In other words, the sub-sections of the corresponding energy beam travel different distances; that is, the beam length or optical path length is different for the two sub-sections. Therefore, if the corresponding energy beam is not properly collimated, the beam diameters of the two sub-sections will be different. By providing this configuration, information relating to the collimation state of the corresponding energy beam and parameters of optics such as lenses can be generated, particularly the focal length of the collimating or focusing optics.

[0022] Advantageously, the second measuring device includes a dichroic beam splitter configured to split the third beam path into a first sub-path extending from the illumination area of ​​the construction plane to the molten pool monitoring unit and a second sub-path reflecting from a surface between the focusing optics and the construction plane to a second beam splitter of the second measuring device, the surface being, in particular, the protective glass of the focusing optics.

[0023] The dichroic beam splitter is configured to split the energy beam or electromagnetic radiation incident on it substantially according to the wavelength of the electromagnetic radiation. Advantageously, the dichroic beam splitter can be configured to split only a small portion or a limited amount of a third energy beam generated by reflection of the energy beam, for example, occurring in the solidified region or at the surface between the building plane and the focusing optics. The main portion of the energy beam can pass through the dichroic filter and proceed in parallel to the second measurement unit.

[0024] Radiation emitted from adjacent areas surrounding the cured region is largely separated from the third energy beam, for example, radiation indirectly generated by areas adjacent to the cured region due to thermal contact. For example, a dichroic beam splitter can be configured to selectively separate or reflect (thermal) radiation emitted from the build plane, for example, in the wavelength spectrum from 250 nm to 3000 nm, with radiation at a wavelength of approximately 1070 nm being reflected only to a small extent. Therefore, if the energy beam is generated at a wavelength of approximately 1070 nm, the energy beam can pass substantially through the dichroic beam splitter, with only a small amount of energy beam being reflected by the dichroic beam splitter. Radiation emitted from the build plane, particularly from areas adjacent to the cured region (where the radiation is in the wavelength spectrum from 250 nm to 3000 nm), passes through the dichroic beam splitter to a small extent, with a larger amount being reflected by the dichroic beam splitter and directed to the melt pool monitoring unit, where radiation emitted from the build plane (i.e., the area adjacent to the cured region) can be measured or analyzed.

[0025] The device can be further improved so that the information generated by the first measuring device includes or relates to:

[0026] -Current beam power,

[0027] - The current focal length of the collimating optics.

[0028] Therefore, by measuring or analyzing the portion of the energy beam extending along the second beam path, the current beam power of the energy beam, which has been collimated by the collimating optics and guided to the first measurement unit, can be characterized. Furthermore, the current focal length of the collimating optics and the effects of temperature changes on the collimating optics can be monitored or characterized. Thus, this embodiment allows for monitoring the collimation of the energy beam, or in other words, for example, deviations caused by temperature, allowing for monitoring whether it is necessary to correct the current focal length or current focus position of the energy beam.

[0029] According to another embodiment of the device, the information generated by the second measuring device includes or relates to:

[0030] -Current focus position

[0031] - Temperature in the irradiated area of ​​the constructed plane,

[0032] -Focus on the optical parameters of the optical device, especially the focal length.

[0033] Similar to the information described previously, monitoring performed by the second measuring device allows for the determination of the current focal position or current optical parameters of the focusing optics, particularly the focal length of the focusing optics. Together with the determined focal length of the collimating optics, the focal length of the optical system comprising the focusing optics and the collimating optics can be determined. Furthermore, the temperature of a region of the construction plane can be determined, where this region can be a curing region in which the energy beam directly irradiates the construction material to cure it, and this region can also be a region adjacent to the curing region that maintains thermal contact with the curing region and is thus indirectly heated by the energy beam.

[0034] By monitoring the temperature of the irradiated area, the quality of the constructed object can be determined. By monitoring and controlling process parameters individually to avoid high temperature gradients or differences between adjacent areas of the object, defects in the object can be avoided.

[0035] Another embodiment of the device proposes a protective glass disposed between the focusing optics and the construction plane, wherein the protective glass is configured to reflect at least a portion of the energy beam. The protective glass provides a surface where the energy beam is partially reflected along a third beam path. Therefore, the reflection of the energy beam at the protective glass can be used to monitor process parameters, since the reflected portion of the energy beam can be evaluated by a second measuring device. This allows characterization of the properties of the focused portion of the energy beam, since the portion of the energy beam reflected at the protective glass has already passed through the collimating optics and the focusing optics.

[0036] The previously described embodiment can be improved by incorporating an optical film located at the focal point of the portion of the energy beam reflected by the protective glass. This embodiment allows for the filtering of different portions of the energy beam or light rays extending along undesirable beam paths. Only a portion of the reflected energy beam from the protective glass can pass through the optical film, which can be adjusted accordingly. Therefore, radiation emitted from uninteresting surfaces or areas, as well as scattered radiation, can be separated from the portion of the energy beam to be evaluated by the film.

[0037] Another embodiment of the device advantageously proposes that at least one piece of information generated by the measuring unit can be transmitted to a quality management system. Therefore, the information generated by the measuring unit can be stored in the data storage of the quality management system and / or further processed, for example, to characterize the object to be built and / or to record process parameters during the object's manufacturing process. This allows for the corresponding association of object features with the corresponding manufacturing process or parameters during the manufacturing process.

[0038] According to another advantageous embodiment, a control unit is provided, configured to control at least one process parameter of an energy beam, particularly the focal position, based on at least one piece of information generated by a measuring unit. Thus, by monitoring the various parts of the energy beam as described above, at least one process parameter can be evaluated and controlled (“online”). By monitoring the relevant process parameters during the manufacturing process of an object, the process parameters can be corrected or adjusted before changes in the process parameters, such as changes in the focal position, cause deviations in the currently manufactured object. Therefore, by evaluating the various parts of the energy beam (e.g., the focusing portion, the reflecting portion, and the collimating portion), the corresponding components can be adjusted, and thus the corresponding parameters can be corrected before deviations occur. Therefore, the position or relative position of optics (e.g., lenses) can be adjusted to compensate for shifts in focal length or focal position due to temperature variations.

[0039] Furthermore, the present invention relates to a method for operating an apparatus for additively manufacturing a three-dimensional object by selectively irradiating and curing layers of building material sequentially, the building material being cured by an energy beam, wherein information relating to the collimation portion of the energy beam and information relating to the focusing portion of the energy beam are generated.

[0040] It is obvious that all features, advantages, and details of the device description can be fully transferred to the method, and vice versa. The method is preferably performed on the device as described above.

[0041] According to one embodiment of the method, the energy beam is divided into a first beam path, a second beam path, and a third beam path between a collimating optics and a focusing optics. The first beam path extends from the collimating optics through the focusing optics to a building plane. The second beam path extends from the collimating optics to a first measuring device. The third optical path extends from the building plane and / or from the surface between the focusing optics and the building plane through the focusing optics to a second measuring device. Information relating to the collimated portion of the energy beam is generated by the first measuring device, and information relating to radiation emitted from the region of the building plane and / or from the surface between the focusing optics and the building plane and / or information relating to the focused portion of the energy beam is generated by the second measuring device.

[0042] Therefore, the energy beam leaving the collimating optics is split by a beam splitter before passing through the focusing optics and being guided to the first measuring unit. Radiation reflected at the construction plane and / or at a surface disposed behind the focusing optics is guided by the beam splitter to the second measuring unit. This allows monitoring of relevant beam portions, particularly the collimated portion, the focused portion, and radiation emitted from the area of ​​the construction plane and / or from the surface between the construction plane and the focusing optics. Attached Figure Description

[0043] Exemplary embodiments of the present invention are described with reference to the accompanying drawings. Figure 1 This is a schematic diagram illustrating the device of the present invention. Detailed Implementation

[0044] The accompanying drawing illustrates an apparatus 1 for additively manufacturing a three-dimensional object 2 by selectively irradiating and curing layers of building material 3 sequentially, the building material being cured by an energy beam 4. The apparatus 1 includes a measuring unit 5 with two measuring devices 14 and 16 configured to generate information relating to the collimated portion 6 of the energy beam 4 and information relating to the focused portion 7 of the energy beam 4. Therefore, the measuring devices 14 and 16 are configured to simultaneously measure different portions 6 and 7 of the energy beam 4, enabling the measuring unit 5 to generate information relating to these different portions 6 and 7 of the energy beam 4.

[0045] The measuring unit 5 includes a first beam splitter 8 that splits the energy beam 4, wherein a first beam path 9 extends from the collimating optics 10 through the first beam splitter 8 and the focusing optics 11 to the construction plane 12. The portion of the energy beam 4 extending along the first beam path 9 is therefore not reflected by the first beam splitter 8 and is used to irradiate the construction material 3 in the construction plane 12.

[0046] The first beam splitter 8 branches off a portion of the energy beam 4 that extends along a second beam path 13 from the collimating optics 10 to the first measuring device 14. Furthermore, the first beam splitter 8 reflects a reflected portion of the energy beam 4, which extends along a third beam path 15 from the building plane 12 or from the surface between the building plane 12 and the focusing optics 11, through the focusing optics 11, to the second measuring device 16. Therefore, the first beam splitter 8 is used to split the energy beam 4, wherein a first beam path 9 passes through the first beam splitter 8, and the second energy beam path 13 is reflected by the first beam splitter 8 to the first measuring device 14, and wherein the third energy beam path 15 is reflected by the first beam splitter 8 to the second measuring device 16.

[0047] The first measuring device 14 includes a second beam splitter 17 that divides a portion of the energy beam 4 extending along the second beam path 13 into a first sub-section 18 and a second sub-section 19. The first sub-section 18 is imaged on a first optical sensor 20, and the second sub-section 19 is measured by a second optical sensor 21. The first optical sensor 20 and the second optical sensor 21 are arranged at different distances from the second beam splitter 17. Therefore, the optical path lengths of the sub-sections 18 and 19 of the energy beam 4 extending along the second beam path 13 are different. This allows measurement of whether the collimated portion 6 of the energy beam 4 is properly collimated, or whether the focal length of the collimating optics 10 must be adjusted. Other parameters of the energy beam 4 and / or the collimating optics 10, such as the power of the energy beam 4, can be measured via the optical sensors 20 and 21.

[0048] The second measuring device 16 is similar in arrangement to the first measuring device 14. Therefore, the same reference numerals are used for the same components. The second measuring device 16 also includes a second beam splitter 17 and two optical sensors 20, 21, wherein the two optical sensors 20, 21 are arranged at different distances from the second beam splitter 17. The second beam splitter 17 of the second measuring device 16 also divides the portion of the energy beam 4 incident on the second beam splitter 17 into a first sub-section 18 and a second sub-section 19.

[0049] Additionally, the second measuring device 16 includes an optical diaphragm 22, which is positioned at the focal point of the portion of the energy beam 4 reflected by the protective glass 23. The diaphragm 22 allows for radiation filtering, wherein only the portion of the energy beam 4 reflected by the protective glass 23 is allowed to pass through the optical diaphragm 22 and be transmitted to the second beam splitter 17 of the second measuring device 16. Radiation other than the portion of the energy beam 4 reflected by the protective glass 23 is blocked by the optical diaphragm 22.

[0050] The measuring unit 5 also includes a dichroic beam splitter 24 assigned to the second measuring device 16, wherein the dichroic beam splitter 24 is configured to selectively filter (reflect) radiation or allow radiation to pass through the dichroic beam splitter 24 according to the wavelength of the radiation. Specifically, portions of the energy beam 4 emitted from the area of ​​the construction plane 12 or reflected at the protective glass 23—that is, extending along the third beam path 15—are filtered by the dichroic beam splitter 24 according to wavelength. This allows filtering of two distinct portions of the energy beam 4, namely, the portion reflected at the protective glass 23 or the construction plane 12, or the portion emitted from the area of ​​the construction plane 12, particularly thermal radiation. Therefore, radiation emitted by the construction plane 12, particularly from the area adjacent to the curing area, can be measured, where the energy beam 4 directly irradiates the construction material 3.

[0051] Specifically, the dichroic beam splitter 24 can be designed such that the wavelength of the energy beam 4 is reflected to a very small extent, or in other words, radiation with the wavelength of the energy beam 4 can pass through the dichroic beam splitter 24 to the greatest extent possible. Therefore, the portion 25 of the energy beam 4 passing through the dichroic beam splitter 24 is primarily the portion of the energy beam 4 that is reflected at the protective glass 23 or the solidified area, passes through the focusing optics 11, and is reflected at the first beam splitter 8. This portion 25 of the energy beam 4 is guided to the second measuring device 16 and filtered again by the optical diaphragm 22, and then split into two sub-portions 18 and 19 by the second beam splitter 17, and imaged onto the optical sensors 20 and 21.

[0052] Furthermore, portion 26 (the thermal radiation emitted by the region of the construction plane 12) is primarily reflected by the dichroic beam splitter 24 because the wavelength of portion 26 differs from the wavelength that the dichroic beam splitter 24 is designed to pass through. Portion 26 is primarily emitted by the construction plane 12, particularly by the region adjacent to the curing area. Therefore, portion 26 is emitted by the construction plane 12 and passes through the protective glass 23 and the focusing optics 11. Subsequently, portion 26 is reflected by the first beam splitter 8 and the dichroic beam splitter 24 and guided to the molten pool monitoring unit 27. The molten pool monitoring unit 27 is configured to measure portion 26; specifically, the molten pool monitoring unit 27 includes at least one optical sensor (not shown) for determining, for example, the temperature of the region emitting portion 26 of the construction plane 12.

[0053] As can be seen from the single accompanying drawing, device 1, particularly measuring unit 5, allows for the determination of the various portions of the energy beam 4 and the radiation emitted from the construction plane 12. Specifically, information relating to the collimating portion 6 and the focusing portion 7, as well as the portion 26 of radiation emitted from the construction plane 12, can be generated. This allows for the adjustment of various process parameters, particularly the focal lengths of the collimating optics 10 and the focusing optics 11, thereby avoiding or correcting focal deviations of the energy beam 4, such as those caused by temperature differences. Furthermore, the temperature gradient between the cured region and the adjacent region can be determined by measuring the temperature in the cured region and the adjacent region. Therefore, if the determined temperature gradient exceeds a predetermined value, the corresponding process parameters, particularly the power of the energy beam 4, can be adjusted, especially by reducing the power.

[0054] Obviously, the above method can be used Figure 1 Execute on device 1 shown.

Claims

1. An apparatus (1) for additively manufacturing three-dimensional objects (2) by selectively irradiating and curing layers of building material (3) that can be cured by means of an energy beam (4) in sequence, characterized in that, The device includes a measuring unit (5), which comprises: Collimating optics (10), focusing optics (11) and a first beam splitter (8) located between the collimating optics (10) and the focusing optics (11); A first measuring device (14) is configured to generate information relating to the collimated portion (6) of the energy beam (4), the information relating to the collimated portion (6) of the energy beam (4) including or relating to the current beam power and / or the current focal length of the collimating optics (10); A second measuring device (16) is configured to generate information relating to the focusing portion (7) of the energy beam (4), including or relating to the current focal position of the focusing optics (11), the temperature in the irradiation area of ​​the building plane (12), and / or the focal length of the focusing optics (11); and A protective glass (23) is disposed between the focusing optics (11) and the construction plane (12), wherein the protective glass (23) is configured to reflect at least a portion of the energy beam (4); The first beam splitter (8) is configured to reflect a portion of the energy beam (4) that has extended through the collimating optics (10), providing the collimated portion (6) of the energy beam (4), and is configured to extend a portion of the energy beam through the focusing optics (11), providing the focused portion (7) of the energy beam (4). The third beam path (15) extends from the protective glass (23), through the focusing optics (11), to the second measuring device (16).

2. The device according to claim 1, characterized in that, At least a portion of the focusing portion (7) of the energy beam (4) defines a first beam path (9) extending through the focusing optics (11) to the construction plane (12), and at least a portion of the collimating portion (6) of the energy beam (4) defines a second beam path (13) extending to the first measuring device (14), and a third beam path (15) extends from the construction plane (12) and the protective glass (23) through the focusing optics (11) to the second measuring device (16). The second measuring device (16) is configured to generate information relating to radiation emitted from the area of ​​the construction plane (12) and to generate information relating to the focusing portion (7) of the energy beam (4).

3. The device according to claim 2, characterized in that, The first measuring device (14) includes a second beam splitter (17) configured to divide the energy beam (4) traveling along the second beam path (13) into two sub-parts (18, 19), and / or the second measuring device (16) includes a second beam splitter (17) configured to divide the portion of the energy beam (4) traveling along the third beam path (15) into two sub-parts (18, 19).

4. The device according to claim 3, characterized in that, The first measuring device (14) and / or the second measuring device (16) include two optical sensors (20, 21), wherein the first sub-part (18) is measured by the first optical sensor (20) and the second sub-part (19) is measured by the second optical sensor (21).

5. The device according to claim 4, characterized in that, At least two optical sensors (20, 21) of the same measuring device (14, 16) are arranged at different distances and / or are movable relative to the second beam splitter (17).

6. The device according to any one of claims 3 to 5, characterized in that, The second measuring device (16) includes a dichroic beam splitter (24) configured to split radiation traveling along the third beam path (15) into a first sub-path and a second sub-path. The first sub-path extends from the region of the construction plane (12) to the molten pool monitoring unit (27), and the second sub-path is reflected from the surface between the focusing optics (11) and the construction plane (12) to the second beam splitter (17) of the second measuring device (16).

7. The device according to claim 1, characterized in that, include: An optical diaphragm (22) is located at the focal point of the energy beam (4) reflected by the protective glass (23).

8. The device according to claim 1, characterized in that, At least one piece of information generated by the measurement unit (5) can be transmitted to the quality management system.

9. The device according to claim 1, characterized in that, include: A control unit configured to control at least one process parameter of the energy beam (4) based on at least one piece of information generated by the measurement unit (5).

10. A measuring unit for use in the apparatus according to any one of claims 1 to 9, characterized in that, The measuring unit (5) includes: Collimating optics (10), focusing optics (11) and a first beam splitter (8) located between the collimating optics (10) and the focusing optics (11); A first measuring device (14) is configured to generate information relating to the collimation portion (6) of the energy beam (4), the information relating to the collimation portion (6) of the energy beam (4) including or relating to the current beam power and / or the current focal length of the collimating optics (10); A second measuring device (16) is configured to generate information relating to the focusing portion (7) of the energy beam (4), including or relating to the current focal position of the focusing optics (11), the temperature in the irradiation area of ​​the building plane (12), and / or the focal length of the focusing optics (11); and A protective glass (23) is disposed between the focusing optics (11) and the construction plane (12), wherein the protective glass (23) is configured to reflect at least a portion of the energy beam (4); The first beam splitter (8) is configured to reflect a portion of the energy beam (4) that has extended through the collimating optics (10), providing the collimated portion (6) of the energy beam (4), and is configured to extend a portion of the energy beam through the focusing optics (11), providing the focused portion (7) of the energy beam (4). The third beam path (15) extends from the protective glass (23), through the focusing optics (11), to the second measuring device (16).

11. A method of operating the device (1) according to claim 1, characterized in that, The method includes: The energy beam is extended through the first beam splitter (8) located between the collimating optics (10) and the focusing optics (11); The first beam splitter (8) reflects a portion of the energy beam (4) that has extended through the collimating optics (10) to provide a collimated portion (6) of the energy beam (4), and the first measuring device (14) generates information relating to the collimated portion (6) of the energy beam (4), including or relating to the current beam power and / or the current focal length of the collimating optics (10); A portion of the energy beam is extended through the focusing optics (11) to provide a focused portion (7) of the energy beam (4), and information relating to the focused portion (7) of the energy beam (4) is generated using a second measuring device (16). This information includes or relates to the current focal position of the focusing optics (11), the temperature in the irradiated area of ​​the building plane (12), and / or the focal length of the focusing optics (11); and The third beam path (15) extends from the protective glass (23) between the focusing optics (11) and the construction plane (12) through the focusing optics (11) to the second measuring device (16).

12. The method according to claim 11, characterized in that, include: A first beam path (9) is extended from the collimating optics (10) through the focusing optics (11) to the building plane (12), the first beam path (9) including at least a portion of the focusing portion (7) of the energy beam (4); The second beam path (13) is extended to the first measuring device (14), the second beam path including at least a portion of the collimated portion (6) of the energy beam (4); The third beam path (15) extends from the construction plane (12) and the protective glass (23) through the focusing optics (11) to the second measuring device (16). Information relating to at least a portion of the collimated portion (6) of the energy beam (4) is generated by the first measuring device (14); and Information relating to the radiation emitted from the area of ​​the construction plane (12) and the focusing portion (7) of the energy beam (4) is generated by the second measuring device (16).

13. The method according to claim 11 or 12, characterized in that, The method is performed on the device according to any one of claims 1 to 9.

Images