Determination method and shaping device

Abstract

This determination method is used in a shaping device configured to shape a three-dimensional shaped object with a shaping material in a powder form by irradiating and melting the shaping material with an energy beam. The determination method includes acquiring measurement information relating to the surface of the shaping material, and determining a surface state of the surface by using height information included in the measurement information.

Description

Determination Method and Modeling Apparatus

[0001] The present invention relates to a technical field of a modeling apparatus for modeling a three-dimensional object, for example, and a determination method used in the modeling apparatus.

[0002] An example of a beam scanning device that scans a processing beam in a modeling apparatus is described in Patent Document 1.

[0003] U.S. Patent No. 7,531,772

[0004] According to a first aspect, there is provided a determination method used in a modeling apparatus that irradiates a powdery modeling material with an energy beam to melt it and models a three-dimensional object with the modeling material, the determination method including obtaining measurement information regarding the surface of the modeling material and determining a surface state of the surface using height information included in the measurement information.

[0005] According to a second aspect, there is provided a modeling apparatus for modeling a three-dimensional object with the modeling material, the modeling apparatus including a supply device capable of supplying a powdery modeling material and a scanning device capable of scanning an energy beam and melting the modeling material supplied by the supply device, the modeling apparatus further including a measurement device that obtains measurement information regarding the surface of the modeling material supplied by the supply device, and a control device that receives the measurement information measured by the measurement device and outputs a surface state of the surface.

[0006] FIG. 1 is a diagram showing a configuration of a processing system according to an embodiment. FIG. 2 is a cross-sectional view showing a configuration of a processing apparatus according to an embodiment. FIG. 3 is a cross-sectional view showing a configuration of a beam scanning device according to an embodiment. FIG. 4 is a perspective view showing a configuration of a beam scanning device according to a modification. FIG. 5 is a diagram showing a configuration of a beam scanning device according to a modification. FIG. 6 is a cross-sectional view showing a configuration of a beam scanning device according to a modification. FIG. 7 is a flowchart showing a detection process according to an embodiment. FIG. 8 is a diagram showing an example of a two-dimensional matrix. FIG. 9 is a diagram showing an example of a binarized image. FIG. 10 is a diagram showing another example of a binarized image. FIG. 11 is a flowchart showing a classification process according to an embodiment. FIG. 12 is a flowchart showing a notification process according to an embodiment.

[0007] In the processing system SYS (processing apparatus 1) shown in Figure 1, additive processing is performed based on powder bed fusion methods such as Selective Laser Sintering (SLS). Based on the three-dimensional model data (three-dimensional model information) of the three-dimensional structure ST to be fabricated, the processing system SYS (processing apparatus 1) sequentially adds multiple structural layers SL on the build plate (114) to fabricate a three-dimensional structure (three-dimensional workpiece).

[0008] In the following explanation, the positional relationships of the various components constituting the processing apparatus 1 will be described using the XYZ Cartesian coordinate system, defined by the mutually orthogonal X, Y, and Z axes. For the sake of explanation, in the following explanation, the X-axis and Y-axis directions will be assumed to be horizontal (i.e., predetermined directions in the horizontal plane), and the Z-axis direction will be assumed to be vertical (i.e., a direction perpendicular to the horizontal plane, essentially the up and down direction). The rotational directions (in other words, tilt directions) around the X, Y, and Z axes will be referred to as the θX direction, θY direction, and θZ direction, respectively. Here, the Z-axis direction may also be considered the direction of gravity. The XY plane may also be considered the horizontal direction.

[0009] (1) Processing apparatus 1 Processing apparatus 1 will be described below.

[0010] (1-1) The configuration of the processing system SYS (processing apparatus 1) will be described with reference to the configuration diagrams 1 and 2 of the processing system SYS (processing apparatus 1). Figure 1 is a schematic diagram showing the configuration of the processing system SYS (processing apparatus 1), and Figure 2 is a cross-sectional view showing the configuration of the processing apparatus 1. The processing system SYS comprises a processing apparatus 1 and a control device 3. The processing apparatus 1 comprises a powder supply device 7, a processing chamber 120 integrated with the powder supply device 7, a light source 4, a beam scanning device 2, and a measuring device 8.

[0011] (1-2) Configuration of the processing chamber 120 The processing chamber 120 (processing chamber) is a box-shaped structure having a rectangular parallelepiped or cubic shape. That is, the processing chamber 120 has a housing 120a having side walls extending perpendicular to the XY plane, a bottom wall extending parallel to the XY plane, and a top wall, and an optical window 120b that closes an opening 1201 provided in the housing 120a (top wall). The optical window 120b is made transparent to the processing light EL and observation light OL, which will be described later. However, the processing chamber 120 may be a box-shaped structure having other shapes, such as a cylindrical, conical, or pyramidal shape.

[0012] The machining chamber 120 separates the internal space of the machining chamber 120, i.e., the chamber space SP120, from the outside of the machining chamber 120. In other words, the machining chamber 120 serves as a housing function to maintain a spatially closed (or substantially closed) machining environment within the chamber space SP120.

[0013] The processing chamber 120 has gas inlet and gas outlet ports (not shown), as well as an opening 1231 through which processing light EL emitted from the beam scanning device 2 can pass. Furthermore, the powder supply device 7 is positioned below the processing chamber 120 so that it is exposed within the chamber space SP 120. As a result, the processing light EL emitted from the beam scanning device 2 may enter the chamber space SP 120 inside the processing chamber 120 through the optical window 120b (opening 1201).

[0014] (1-3) Components of the powder supply device 7 The powder supply device 7 comprises a build cylinder 115, a carrier 111, a carrier transfer device 113, and a material coating device 112 (Figure 2).

[0015] The carrier 111 is a member that supports the build plate 114. The build cylinder 115 is a cylindrical body and is arranged to surround the build plate 114. In this way, the molding material M can be stored (contained) inside the recess formed by the carrier 111 and the build cylinder 115. The molding material M is, for example, a powder, and metal powder or resin powder can be used.

[0016] The carrier 111 is made movable (up and down) within the build cylinder 115 in the cylindrical axis direction (through direction, vertical direction (Z direction)) of the build cylinder 115 by the carrier moving device 113. In this embodiment, the carrier 111 is configured to function as a guide member that restricts movement in directions other than the Z direction while allowing movement in the Z direction, thereby enabling movement along the Z direction. However, the configuration is not limited to this, and the carrier moving device 113 may be made movable forward and backward along the cylindrical axis direction (through direction, vertical direction (Z direction)) of the build cylinder 115, thereby enabling the carrier 111 to move forward and backward in the cylindrical axis direction of the build cylinder 115. In this way, the powder supply device 7 is made capable of moving (lowering and raising) the carrier 111 continuously or in steps of a predetermined height.

[0017] The material coating device 112 includes a blade B (recoater blade, recoater), a powder supply unit D (dispenser, buffer), and a powder recovery unit C (collector). The powder supply unit D is a storage unit for the molding material M supplied from a supply path (not shown) and is where the molding material M is deposited. The tip of the blade B extends in a straight line in the X direction and is movable in the Y direction by a drive source (not shown). In other words, the tip of the blade B is configured to move in a horizontal plane. In this embodiment, the extension direction of the blade B and the movement direction of the blade B are perpendicular to each other, but it is sufficient if at least the extension direction of the blade B and the movement direction of the blade B intersect.

[0018] As described above, blade B is configured to move sequentially above the powder supply unit D, above the recess formed by the carrier 111 and build cylinder 115, and then above the powder recovery unit C, by a drive source (not shown). As blade B moves, the molding material M accumulated in the powder supply unit D is spread (supplied) onto the recess formed by the carrier 111 and build cylinder 115, and subsequently onto the build plate 114, or onto the object being molded, and the surface of the molding material M is smoothed by blade B. In this way, a material layer ML made of the molding material M can be formed on the recess formed by the carrier 111 and build cylinder 115, and subsequently onto the build plate 114, or onto the object being molded. The molding material M that was not used to form the material layer ML is transported to the powder recovery unit C as blade B moves above the powder recovery unit C. The molding material M moved by the movement of blade B falls into the powder recovery unit C. The powder recovery unit C recovers the fallen molding material M. Alternatively, a flow path may be provided from the powder recovery unit C to the powder supply unit D, and the recovered molding material M may be supplied to the powder supply unit D.

[0019] (1-4) Configuration of Light Source 4 Light source 4 is a light source that irradiates processing light EL. In this embodiment, a light source 4 that generates infrared light as processing light EL is used. That is, light source 4 generates processing light EL with a peak wavelength of 1000 nm or a wavelength (wavelength band) near 1000 nm. In this embodiment, a light source 4 that generates infrared light is used, but it is not limited to this. Light source 4 may generate light other than infrared light, for example, at least one of visible light and ultraviolet light as processing light EL. Furthermore, although it is called processing light EL, it is not limited to light, and any material that can be used as a heat source for processing, similar to light, may be used, for example, a material that generates an electron beam. In addition, in this embodiment, a light source 4 that can change the cross-sectional intensity profile (cross-sectional power distribution) of the emitted processing light EL may be used.

[0020] The processing light EL generated by the light source 4 is supplied from the light source 4 to the beam scanning device 2. In this embodiment, since laser light was used as the processing light EL, it was supplied from the light source 4 to the beam scanning device 2 using an optical fiber 5. The optical fiber 5 may also be called a beam transmission member. However, the supply of processing light EL from the light source 4 to the beam scanning device 2 is not limited to this configuration. Processing light EL in a converged state (focused state) or processing light EL as parallel light may be incident on the beam scanning device 2, and the focusing optical system 2, and the processing light EL may be focused by the focusing optical system 21. Alternatively, the processing light EL may be propagated through space without using an optical fiber 5 and incident on the beam scanning device 2 from the light source 4.

[0021] (1-5) Configuration of the beam scanning device 2 Next, the configuration of the beam scanning device 2 will be described with reference to Figures 1 and 3. Figure 3 is a perspective view showing the configuration of the beam scanning device 2. The beam scanning device 2 is provided above the processing chamber 120, and processing light EL can be irradiated into the chamber space SP 120 through an opening 1231 provided in the processing chamber 120. In Embodiment 1, the beam scanning device 2 is provided with a space between it and the processing chamber 120 to suppress the transfer of heat from the processing chamber 120 to the beam scanning device 2. However, the beam scanning device 2 may be mounted so as to be in contact with the processing chamber 120 without a space separating them. The beam scanning device 2 includes a focusing optical system 21, a beam branching member 22, a scanning optical member 23, a light receiving device 24, and a housing 25.

[0022] (1-5-1) Configuration of the enclosure 25 The enclosure 25 has a bottom wall 2540, a top wall 2560, side walls 2550, 2551, and two additional side walls (not shown), and is a box-shaped structure having a rectangular parallelepiped or cubic shape.

[0023] The bottom wall 2540 extends along the XY plane. The side walls 2550 and 2551 extend along the XZ plane, facing each other at a distance, and their respective lower ends (the -Z ends) are connected to the orthogonal bottom wall 2540. The top wall 2560 extends along the XY plane so as to face the bottom wall 2540 at a distance, and is connected to the upper ends (the +Z ends) of the side walls 2550 and 2551. In addition, two side walls (not shown) each extend along the YZ plane, facing each other at a distance in the X direction, and their four sides are connected to the bottom wall 2540, top wall 2560, and side walls 2550 and 2551. Note that the housing 25 is not limited to the rectangular parallelepiped or cubic shape described above, but may be a box-shaped structure of other shapes.

[0024] Furthermore, the housing 25 or a part of the housing 25 may be formed of a low thermal expansion material such as Invar, and may be made of aluminum, stainless steel, or a composite thereof. Also, some of the multiple components constituting the housing may be made of a different material from the other components. When multiple components are made of different materials, flexures may be formed in at least some of the multiple components to reduce distortion due to differences in thermal expansion coefficients.

[0025] The housing 25 has at least one opening. The opening spatially connects the inside (housing space SP25) of the housing 25 to the outside space, or is an opening that can transmit electromagnetic waves such as light or electron beams. In the following description, we will explain an example in which three openings 251, 252, and 253 are formed in the housing 25, as shown in Figure 3, and an optical window 2510 is provided in opening 251, an optical window 2520 in opening 252, and an optical window 2530 in opening 253.

[0026] Specifically, the bottom wall 2540 of the housing 25 has an opening 251 formed therein, which corresponds to a through hole that penetrates the bottom wall 2540 in the Z direction. An optical window 2510 is positioned in this opening 251. The optical window 2510 is an optical element through which the processed light EL can pass.

[0027] Furthermore, an opening 252, corresponding to a through hole that penetrates the side wall 2550 in the Y direction, is formed in the side wall 2550 of the housing 25. An optical window 2520 is positioned in this opening 252.

[0028] Furthermore, an opening 253, which corresponds to a through hole penetrating the upper wall 2560 of the housing 25 in the Z direction, is formed in the upper wall 2560. An optical window 2530 is positioned in this opening 253.

[0029] Optical windows 2510 and 2520 are designed to transmit at least the processing light EL, and optical windows 2510 and 2530 are designed to transmit the observation light OL. The observation light OL is light from the object being observed, for example, light emitted from the material layer ML, and ultimately from the molten metal. In this embodiment, optical windows 2510, 2520, and 2530 are optical members that do not have power (i.e., do not have refractive power), but they are not limited to this and may be optical members that do have power (i.e., have refractive power). When an electron beam is used instead of the processing light EL, optical windows 2510, 2520, and 2530 are made of materials that can transmit the electron beam.

[0030] In this embodiment, the housing 25 is closed off by optical windows 2510 at opening 251, 252 at opening 252, and 253 at opening 253. Although optical windows 2510, 2520, and 2530 are not essential components, providing them makes the interior of the housing 25 (housing space SP25) a closed space, isolating it from the space outside the housing 25. Therefore, the possibility of unwanted substances (e.g., dust or debris) present outside the housing 25 entering the housing space SP25 inside the housing 25 through openings 251, 252, and 253 can be reduced. Consequently, unwanted substances that enter the housing space SP25 can block the processed light EL, preventing unintended changes in the characteristics of the processed light EL (e.g., intensity or intensity distribution).

[0031] The housing 25 houses the focusing optical system 21, the beam branching member 22, and the scanning optical member 23 in an internal housing space SP 25. In this embodiment, the housing 25 does not house the light receiving device 24 in the housing space SP 25, but it may be configured to house some or all of the components of the light receiving device 24. The processed light EL emitted from the light source 4 is incident on the beam scanning device 2. More specifically, in this embodiment, the processed light EL emitted from the light source 4 propagates through the optical fiber 5 and is incident on the housing 25, i.e., the beam scanning device 2, through the exit end 51 of the optical fiber 5 and the opening 252 (optical window 2520).

[0032] (1-5-2) Configuration of the focusing optical system 21 The processing light EL that is incident on the beam scanning device 2 through the aperture 252 (optical window 2520) is incident on the focusing optical system 21. The focusing optical system 21 is an optical system that focuses the processing light EL that is incident on the beam scanning device 2. Specifically, the focusing optical system 21 is an optical system that focuses the processing light EL that is incident on the beam scanning device 2 onto the material layer ML.

[0033] The configuration of the focusing optical system 21 will be described with reference to Figure 3. The focusing optical system 21 is positioned between the incident position where the processed light EL is incident on the beam scanning device 2 (specifically, the position where the optical window 2520 is located) and the beam branching member 22. The focusing optical system 21 comprises a front optical system 211, a rear optical system 212, a reflective mirror (reflective member) 2131, and a reflective mirror (reflective member) 2132. More specifically, the focusing optical system 21 is configured such that the processed light EL emitted from the exit end 51 of the optical fiber 5 is incident sequentially on the front optical system 211, the reflective mirror 2131, the reflective mirror 2132, and the rear optical system 212. As a result, the front optical system 211 works in cooperation with the rear optical system 212 to focus the processed light EL that is incident on the front optical system 211 in a divergent state. In particular, the front optical system 211 works in cooperation with the rear optical system 212 to focus the processing light EL that is incident on the front optical system 211 in a divergent state onto the material layer ML.

[0034] In this embodiment, a reflective mirror 2131 and a reflective mirror 2132 are provided between the front optical system 211 and the rear optical system 212. In other words, with respect to the reflective mirrors 2131 and 2132, the optical system located upstream in the direction of light propagation is the front optical system 211, and the optical system located downstream in the direction of light propagation is the rear optical system 212.

[0035] The focusing optical system 21 may include one or more apertures that define the beam diameter of the processed light EL. The one or more apertures may be positioned at least one of the following locations: on the incident side of the movable lens 2111 and around the fixed lens 2122. The temperature of the one or more apertures may be adjustable by a temperature control device 28d, which will be described later using Figure 10.

[0036] (a) Configuration of reflective mirrors 2131 and 2132 The reflective mirror 2131 reflects the processing light EL incident from the front optical system 211 toward the reflective mirror 2132. More specifically, the reflective mirror 2131 reflects the processing light EL that has traveled along the optical axis (Y direction) of the front optical system 211 toward a direction intersecting the optical axis of the front optical system 211 such that the optical path of the processing light EL is folded back. In particular, the reflective mirror 2131 reflects the processing light EL such that the optical path of the processing light EL from the reflective mirror 2131 toward the reflective mirror 2132 is located between the front optical system 211 and the rear optical system 212.

[0037] Then, the reflective mirror 2132 reflects the processing light EL reflected by the reflective mirror 2131 toward the rear optical system 212. More specifically, the reflective mirror 2132 reflects the processing light EL that has traveled from the reflective mirror 2131 toward the rear optical system 212 in such a way that it folds back so that it travels along the Y direction.

[0038] Therefore, the reflective mirrors 2131 and 2132 are deflection mirrors that bend the optical path and / or optical axis, and in this embodiment, the optical path of the processed light EL is folded using the reflective mirrors 2131 and 2132. For this reason, although it is not an essential configuration for achieving the function of the focusing optical system 21, by providing a configuration with reflective mirrors 2131 and 2132, the length of the focusing optical system 21 in the direction of propagation (Y direction) of the processed light EL incident on the focusing optical system 21 can be reduced, and consequently the size of the housing 25 that houses the focusing optical system 21 and the beam scanning device 2 can also be reduced.

[0039] In this embodiment, the reflective mirror 2131 is positioned above the reflective mirror 2132 and the rear optical system 212 (i.e., on the +Z side), and the reflective mirror 2132 is positioned below the front optical system 211 (i.e., on the -Z side). However, this is not the only configuration. That is, the reflective mirror 2131 may be shifted relative to the reflective mirror 2132 and the rear optical system 212 in one direction intersecting the direction of propagation (Y direction) of the processing light EL incident on the focusing optical system 21, and the reflective mirror 2132 may be shifted relative to the front optical system 211 in the other direction intersecting the direction of propagation (Y direction) of the processing light EL incident on the focusing optical system 21.

[0040] (b) Configuration of the front optical system 211 In this embodiment in particular, as the optical fiber 5 propagates, the processing light EL is repeatedly reflected inside the optical fiber 5, so that a divergent state is emitted from the exit end 51 of the optical fiber 5. In other words, the processing light EL, which is divergent light, is incident on the focusing optical system 21. For this reason, the focusing optical system 21 first converts the divergent state processing light EL that has been incident on the beam scanning device 2 in the front optical system 211 into light that can be incident on the rear optical system 212. The front optical system 211 includes a movable lens 2111 and a fixed lens 2112.

[0041] The movable lens 2111 is the incident optical element among the multiple optical elements of the focusing optical system 21, positioned furthest to the incident side (upstream in the direction of propagation of the processed light EL), and is incident on the processed light EL emitted from the exit end 51 of the optical fiber 5. In this embodiment, the movable lens 2111 is a positive lens (convex lens). In other words, the movable lens 2111 has positive power (or, to put it another way, positive refractive power).

[0042] Here, we will explain the case where the movable lens 2111, which is the incident optical element, is a negative lens (concave lens). When the movable lens 2111 is a negative lens, the diverging processed light EL is further diverged by the movable lens 2111. In other words, the divergence angle of the processed light EL that has passed through the movable lens 2111 becomes larger than the divergence angle of the processed light EL that has been incident on the movable lens 2111. As a result, the processed light EL may be excessively diverged to the point that some of the processed light EL that has passed through the movable lens 2111 does not enter the fixed lens 2112, and furthermore, the elements of the rear optical system 212 (movable lens 2121, fixed lens 2122).

[0043] Therefore, in this embodiment, the movable lens 2111 is set as a positive lens, and the configuration is such that the diverging processing light EL is not further diverged by the movable lens 2111. In other words, the divergence angle of the processing light EL that has passed through the movable lens 2111 is set to be smaller than the divergence angle of the processing light EL that has been incident on the movable lens 2111. As a result, the processing light EL that has passed through the movable lens 2111 is incident on the fixed lens 2112 and, consequently, on each element of the rear optical system 212 (movable lens 2121, fixed lens 2122) without any leakage, and consequently, the loss of processing light EL is suppressed. However, if such technical problems do not occur, the movable lens 2111 may be a negative lens.

[0044] Also, the movable lens 2111 is movable along the direction along the optical axis of the movable lens 2111 (in the example shown in FIG. 3, the Y direction). More specifically, the movable lens 2111 is configured to be driven (in other words, moved) by an actuator 2141 (FIG. 1) that functions as a driving member so as to be able to change the relative position (particularly the distance in the optical axis direction) with respect to the housing 25 and thus the fixed lens 2112.

[0045] On the other hand, the fixed lens 2112 is fixed in the housing 25 so that its position does not change. The processed light EL that has passed through the movable lens 2111 is incident on the fixed lens 2112. At least a part of the processed light EL incident on the fixed lens 2112 passes through the fixed lens 2112. FIG. 3 shows an example where the fixed lens 2112 is a negative lens, but the fixed lens 2112 may be a positive lens. Note that the fixed lens 2112 is provided as a configuration for improving the aberration correction ability, but is not necessarily an essential configuration and may not be provided.

[0046] (c) Configuration of the rear group optical system 212 The rear group optical system 212 condenses the processed light EL from the front group optical system 211. That is, the rear group optical system 212 condenses the processed light EL that has entered the rear group optical system 212 from the front group optical system 211 (fixed lens 2112) via the reflection mirrors 2131 and 2132. The rear group optical system 212 includes a movable lens 2121 and a fixed lens 2122.

[0047] The movable lens 2121 is an optical member arranged on the most incident side (the upstream side in the traveling direction of the processed light EL) among the plurality of optical members included in the rear group optical system 212. After passing through the fixed lens 2112, the movable lens 2121 transmits the processed light EL that has entered through the reflection mirrors 2131 and 2132 and emits it to the fixed lens 2122. The movable lens 2121 is a negative lens (concave lens). That is, the movable lens 2121 has a negative power (in other words, has a negative refractive power). However, the movable lens 2121 may be a positive lens. The movable lens 2121 is movable along the direction along the optical axis of the movable lens 2121 (in the example shown in FIG. 3, the Y direction). More specifically, the movable lens 2121 is configured to be driven (in other words, moved) by an actuator 2142 (FIG. 1) that functions as a driving member so that the relative position (particularly the distance in the optical axis direction) with the housing 25 and thus the fixed lens 2122 can be changed.

[0048] The fixed lens 2122 is the final optical member arranged on the most emission side (the downstream side in the traveling direction of the processed light EL) among the plurality of optical members included in the condensing optical system 21. The fixed lens 2122 emits the processed light EL that has passed through the fixed lens 2122 to the beam splitting member 22. The fixed lens 2122 is fixed in the housing 25 so that its position does not change. In other words, the fixed lens 2122 is fixed so that its positional relationship with the beam splitting member 22 does not change (in other words, is maintained). In the present embodiment, the fixed lens 2122 uses a positive lens (convex lens). That is, the fixed lens 2122 has a positive power (in other words, has a positive refractive power).

[0049] Here, a case where the fixed lens 2122 is a negative lens will be described. When the fixed lens 2122 is a negative lens, the condensing optical system 21 (particularly, the rear group optical system 212) may cause the processed light EL that has passed through the fixed lens 2122 to become divergent light and the processed light EL may not be condensed.

[0050] Therefore, in this embodiment, a positive lens is used as the fixed lens 2122, which is the final optical component. As a result, the focusing optical system 21 (especially the rear group optical system 212) can properly focus the processed light EL. In order to lengthen the back focus of the focusing optical system 21, the fixed lens 2122 as the final optical component may have a negative refractive power. In this case, the movable lens 2121 may have a positive refractive power.

[0051] Furthermore, the beam scanning device 2 fixes the position of the fixed lens 2122, which is the final optical component, and moves the other lenses in order to change the focusing position and the spot size of the processing light EL. Here, if the numerical aperture (NA) of the focusing optical system 21 is predetermined, the size of the fixed lens 2122, which is the final optical component, increases as the working distance of the processing device 1 (for example, the distance between the beam scanning device 2 and the carrier 111) increases. Considering that it becomes more difficult to move the fixed lens 2122 as its size increases, in this embodiment the beam scanning device 2 has the advantage of being able to keep the fixed lens 2122, which may be relatively large, fixed.

[0052] (d) With respect to the movable lenses 2111 and 2121, the focusing optical system 21 is configured not to form a focal point between the incident optical member (movable lens 2111) and the final optical member (fixed lens 2122), but is not limited to this configuration. Although it is preferable not to form a focal point where the intensity is high between the incident optical member and the final optical member, even if a focal point is formed, it is rare for the focal point of the processed light EL to be located on the optical members of the focusing optical system 21 (for example, the movable lens 2111, the fixed lens 2112, the movable lens 2121, the fixed lens 2122, the reflective mirror 2131 and the reflective mirror 2131), and the possibility of damaging the optical members of the focusing optical system 21 is low. For this reason, the focusing optical system 21 may form a focal point between the incident optical member and the final optical member.

[0053] Furthermore, if the processing device 1 is equipped with only one of the two movable lenses 2111 and 2121, the focusing position of the processing light EL can be changed so that the focusing position of the processing light EL is set to a desired position. Also, if the processing device 1 is equipped with only one of the two movable lenses 2111 and 2121, the spot size of the processing light EL can be changed so that the spot size of the processing light EL is a desired size. However, if only one of the two movable lenses 2111 and 2121 is equipped, it is not easy to change the focusing position of the processing light EL and change the spot size of the processing light EL simultaneously.

[0054] Therefore, it is preferable that the processing apparatus 1 is equipped with two movable lenses 2111 and 2121, and that the focusing position of the processing light EL and the spot size of the processing light EL can be changed by moving the two movable lenses 2111 and 2121. This allows the processing apparatus 1 to change the focusing position of the processing light EL and the spot size of the processing light EL so that the focusing position of the processing light EL is set to a desired position and the spot size of the processing light EL is set to a desired size.

[0055] Furthermore, if the optical path of the processing light EL between the movable lens 2111 and the movable lens 2121 is short, relatively large aberrations may occur. However, in this embodiment, the optical path of the processing light EL between the movable lens 2111 and the movable lens 2121 is made longer. As a result, the beam scanning device 2, and by extension the processing device 1, can reduce aberrations while minimizing the amount of movement of at least one of the movable lenses 2111 and 2121 necessary to change the focusing position and spot size of the processing light EL by a certain amount.

[0056] Furthermore, by increasing the power of at least one of the movable lenses 2111 and 2121 (i.e., increasing the refractive power), it is possible to reduce the amount of movement of at least one of the movable lenses 2111 and 2121 required to change the focusing position and spot size of the processed light EL by a certain amount. However, in this case, a relatively large aberration may occur due to the increased power of at least one of the movable lenses 2111 and 2121. In addition, because the weight of the movable lenses 2111 and 2121 increases due to the increased power of at least one of the movable lenses 2111 and 2121, the controllability of the focusing position and spot size of the processed light EL may decrease.

[0057] In this embodiment, instead of unnecessarily increasing the power of at least one of the movable lenses 2111 and 2121, the beam scanning device 2 relatively lengthens the optical path of the processing light EL between the movable lens 2111 and the movable lens 2121. As a result, the beam scanning device 2 can reduce aberrations while reducing the amount of movement of at least one of the movable lenses 2111 and 2121 required to change the focusing position and spot size of the processing light EL by a certain amount. In addition, it is possible to suppress an increase in the weight of the movable lenses 2111 and 2121, and to suppress a decrease in the controllability of the focusing position and spot size of the processing light EL.

[0058] Furthermore, when the observation light OL passes through the focusing optical system 21 (especially through the movable lenses 2111 and 2121) and enters the light receiving device 24, the focusing optical system 21 needs to reduce chromatic aberration caused by the difference in wavelength bands between the processing light EL and the observation light OL. For example, the focusing optical system 21 needs to be equipped with an achromatic lens to reduce chromatic aberration caused by the difference in wavelength bands between the processing light EL and the observation light OL. In other words, reducing chromatic aberration may make the configuration of the focusing optical system 21 more complex and potentially increase the weight of the focusing optical system 21.

[0059] Therefore, it is preferable that the observation light OL is incident on the light receiving device 24 without passing through the focusing optical system 21 through which the processing light EL passes. In particular, it is preferable that the observation light OL is incident on the light receiving device 24 without passing through the movable lenses 2111 and 2121 provided in the focusing optical system 21. This simplifies the configuration of the focusing optical system 21 and prevents the weight of the focusing optical system 21 from becoming heavy.

[0060] (1-5-3) Configuration of the beam branching member 22 The beam branching member 22 is positioned on the optical path of the processed light EL between the focusing optical system 21 (in particular, the fixed lens 2122 which is the final optical component) and the scanning optical component 23. The beam branching member 22 is positioned between the focusing optical system 21 (in particular, the fixed lens 2122 which is the final optical component) and the scanning optical component 23, and in this embodiment in particular, is positioned so as to be aligned in a straight line in the direction of propagation (Y direction) of the processed light EL irradiated from the focusing optical system 21.

[0061] Here, the wavelength band of the processing light EL and the wavelength band of the observation light OL are different. Specifically, the processing light EL is light in the first wavelength band with a peak wavelength of 1000 nm or a wavelength close to 1000 nm. On the other hand, the light emitted from the melt pool, and by extension from the molten metal, is light in the second wavelength band from 400 nm to 800 nm, or light in the third wavelength band from 1200 nm to 1700 nm. Therefore, in this embodiment, as the observation light OL, both or either of the light in the second wavelength band from 400 nm to 800 nm and the light in the third wavelength band from 1200 nm to 1700 nm are used. To observe the observation light OL, a dichroic mirror with optical properties that reflects light in the wavelength band of the observation light OL and transmits light in the wavelength band of the processing light EL is used as the beam splitting member 22. A dichroic mirror is a substantially parallel-plate-shaped optical element, for example, having a circular, rectangular, or polygonal shape in a plan view. The beam splitting member 22 (dichroic mirror) is positioned on the reflective surface at a location where the angle between the normal direction of the reflective surface and the optical axis toward the scanning optical element 23 is equal to the angle between the normal direction of the reflective surface and the optical axis toward the light receiving device 24.

[0062] As a result, the processing light EL incident on the beam branching member 22 from the focusing optical system 21 passes through the beam branching member 22 and can be incident on the scanning optical member 23. On the other hand, the light incident on the beam branching member 2 from the scanning optical member 23 (observation light OL, described later) has its direction of travel changed in the beam branching member 22 and can be incident on the light receiving device 24 through the aperture 253 (optical window 2530).

[0063] The beam splitting member 22 can be a dichroic mirror, a dichroic prism, an amplitude-type beam splitter, or any other object that transmits incident light from one side while changing the direction of propagation of incident light from the other side. In addition, the beam splitting member 22 may be a polarizing beam splitter, for example, when a light source 4 that supplies linearly polarized processing light EL is used. The polarizing beam splitter may be an optical element with a polarization separation film formed on it, or it may be a Brewster plate mirror. In this configuration, the linearly polarized processing light EL from the light source 4 is allowed to pass through the polarizing beam splitter, while at least a portion of the unpolarized observation light incident on the polarizing beam splitter via the scanning optical element 23 is reflected toward the aperture 253. Therefore, the polarizing beam splitter used as the scanning optical element 23 is arranged such that the polarization direction of the observation light OL is p-polarized relative to the polarization separation surface, and the polarization direction of the observation light OL is s-polarized relative to the polarization separation surface, corresponding to the polarization direction.

[0064] (1-5-4) Configuration of the scanning optical member 23 The scanning optical member 23 is configured to scan the surface of the processing light EL incident on the scanning optical member 23 from the beam branching member 22. In other words, the scanning optical member 23 is configured to move on the surface of the material layer ML over the irradiation area to which the processing light EL is irradiated.

[0065] In this embodiment, an example is shown in which a galvanometer mirror is used as the scanning optical element 23. The galvanometer mirror is an optical element that changes the emission direction of the processing light EL emitted from the galvanometer mirror by deflecting the processing light EL. For this reason, the galvanometer mirror may also be called a deflection optical system. In addition to the galvanometer mirror, the scanning optical element 23 may be at least one of a polygon mirror, a resonant mirror, and an AOD (acousto-optic deflector).

[0066] The scanning optical element (galvanometer mirror) 23 comprises a scanning mirror 231, a scanning mirror 232, and an actuator 233 (Figure 1). The scanning mirrors 231 and 232 are reflective members capable of reflecting at least light in the wavelength band of the processing light EL and light in the wavelength band of the observation light OL. The actuator 233 is connected to the control device 3 and functions as a driving member that drives (in other words, moves) the scanning mirrors 231 and 232, respectively. Specifically, the actuator 233 includes a first actuator that drives the scanning mirror 231 and a second actuator that drives the scanning mirror 232.

[0067] The scanning mirror 231 is made oscillating or rotating around a rotation axis extending in either the X or Y direction by an actuator 233 (first actuator). In other words, in this embodiment, the scanning mirror 231 can be positioned at a desired angle with respect to a reference, i.e., any orientation, by the actuator 233 (first actuator) around a rotation axis extending in the X direction.

[0068] Furthermore, the scanning mirror 232 is made oscillating or rotating by actuator 233 (second actuator) around a rotation axis that is perpendicular to the rotation axis of the scanning mirror 231, that is, along the other of the X and Y directions. In other words, in this embodiment, the scanning mirror 231 can be set to a desired angle with respect to a reference, i.e., any orientation, by actuator 233 (second actuator) around a rotation axis that extends along the Y direction.

[0069] Therefore, the scanning optical member 23 drives the actuator 233 (first actuator) based on the control device 3 to drive around a rotation axis (X direction) extending along one side, and deflects the light incident on the scanning mirror 231 from the beam branching member 22 with processing light EL. Then, based on the control device 3, the actuator 233 (second actuator) is driven to drive around a rotation axis (Y direction) extending along the other side, and deflects the light incident on the scanning mirror 232 from the scanning mirror 231 with processing light EL. As a result, the scanning optical member 23 (scanning mirror 232) can irradiate (emit) processing light EL scanning in the desired direction onto the surface of the material layer ML through the aperture 251 (optical window 2510). (1-5-5) Configuration of the light receiving device 24 As described above, the processing device 1 melts the material layer ML, and by extension the molding material M, by irradiating the surface of the material layer ML with processing light EL. This generates radiant light emitted from the molten molding material M, as well as scattered light from the processing light EL scattered (reflected) by the material layer ML and, consequently, by the molding material M.

[0070] Therefore, the processing apparatus 1 is equipped with a light-receiving device 24 that can image the object to be observed. Specifically, the light-receiving device 24 is equipped with a light-receiving element 24a and an output unit 24b that outputs the acquired information to the outside. By using an image sensor such as a CMOS (Complementary Metal Oxide Semiconductor) or a CCD (Charge Coupled Devices) as the light-receiving element 24a, it is possible to acquire not only brightness information but also information such as the position of the light-emitting region within the imaging area (position information) and information about the size of the light-emitting region (size information). The light-receiving device 24 may also have a focusing optical system that can focus the observation light OL and direct it into the light-receiving element 24a as needed.

[0071] The processing apparatus 1 is configured such that the light generated by the irradiation of the processing light EL is sequentially incident on the scanning mirror 232 and scanning mirror 231 through the aperture 251 (optical window 2510), the direction of propagation is changed by the beam branching member 22, and then incident on the light receiving device 24 through the aperture 253 (optical window 2530). In other words, the processing light EL and the observation light OL share the same path from the beam branching member 22 to the surface of the material layer ML, but differ in that their respective directions of propagation are opposite.

[0072] The light receiving device 24 detects the received observation light OL with the light receiving element 24a and is capable of outputting the obtained information to the control device 3 via the output unit 24b. Specifically, the light receiving device 24 acquires luminance information directly obtained with the light receiving element 24a, image information obtained by imaging the observation light OL with the light receiving element 24a, video information obtained by photographing the observation light OL with the light receiving element 24a, and at least one of the following: luminance information, position information, and size information extracted from this information, and is capable of outputting these to the control device 3 via the output unit 24b.

[0073] (1-6) Configuration of the measuring device 8 The measuring device 8 may measure the molding material M (in other words, the powder bed) stored in the recess (see Figure 2) formed by the carrier 111 and the build cylinder 115. Note that the measuring device 8 is not shown in Figure 2. For example, the measuring device 8 may be positioned in the processing chamber 120 (i.e., the chamber space SP 120) in a location that does not interfere with the processing light EL. The measuring device 8 may be configured to be movable within the chamber space SP 120. Note that the measuring device 8 may not be limited to measuring the molding material M, but may also perform real-time observation (in other words, live view) of the inside of the processing chamber 120. In this case, the measuring device 8 may be called an observation device.

[0074] The measuring device 8 may have at least one of an imaging device and a laser scanner. The imaging device may be a stereo camera. The laser scanner may be a three-dimensional scanner. If the measuring device 8 has a stereo camera, the measuring device 8 may generate shape data indicating the three-dimensional shape of the object to be measured (e.g., molding material M) based on two image data outputs from the two cameras constituting the stereo camera. The shape data may be three-dimensional point cloud data. For example, the measuring device 8 may generate three-dimensional point cloud data by calculating the distance from the two cameras to the object to be measured based on the difference in the position of the object to be measured on the two images captured by the two cameras constituting the stereo camera (i.e., parallax), the focal length of each of the two cameras, and the distance between the two cameras (i.e., baseline length). Note that the shape data is not limited to three-dimensional point cloud data, but may be data representing existing three-dimensional information, such as depth image data in which the distance from the stereo camera to the object to be measured is associated with the brightness value of each pixel.

[0075] The measuring device 8 may also have a projector in addition to the stereo camera. The projector may project light having a predetermined pattern (in other words, a predetermined intensity distribution) onto the object to be measured (for example, the molding material M). The stereo camera may image the object to be measured onto which light having the predetermined pattern has been projected. With this configuration, for example, even when the surface of the object to be measured is relatively dark, and / or when the surface of the object to be measured has relatively few feature points, the measuring device 8 can generate highly accurate shape data with little influence from external disturbances.

[0076] If the measuring device 8 has a laser scanner, the measuring device 8 may generate three-dimensional point cloud data (in other words, shape data) that shows the three-dimensional shape of the object to be measured, based on the measurement results of the laser scanner. The laser scanner may be a time-of-flight type laser scanner or a phase-shift type laser scanner.

[0077] (1-7) Configuration of the control device 3 As shown in diagram 1, the control device 3 comprises an arithmetic unit 31 and a storage device (recording device) 32. The arithmetic unit 31 may include, for example, at least one of a CPU (Central Processing Unit) and a GPU (Graphics Processing Unit). The storage device 32 may include, for example, memory. The control device 3 functions as a device that controls the operation of the processing device 1 by having the arithmetic unit 31 execute a computer program. The computer program supports the operation procedures, such as arithmetic processing, that the arithmetic unit 31 is to perform (i.e., execute). The computer program executed by the arithmetic unit 31 may be recorded in the storage device 32 (i.e., recording medium) provided in the control device 3, or it may be recorded in any storage medium (e.g., hard disk or semiconductor memory) that is built into the control device 3 or can be attached to the control device 3 externally. Alternatively, the arithmetic unit 31 may download the computer program to be executed from an external device of the control device 3 via a network interface.

[0078] For example, the control device 3 may be provided outside the processing device 1 as a server or the like. In this case, the control device 3 and the processing device 1 may be connected by a wired and / or wireless network (or a data bus and / or communication line). As a wired network, a network using a serial bus interface, such as at least one of IEEE 1394, RS-232x, RS-422, RS-423, RS-485, and USB, may be used. As a wired network, a network using a parallel bus interface may be used. As a wired network, a network using an Ethernet® compliant interface, such as at least one of 10BASE-T, 100BASE-TX, and 1000BASE-T, may be used. As a wireless network, a network using radio waves may be used. An example of a network using radio waves is a network compliant with IEEE 802.1x (for example, at least one of wireless LAN and Bluetooth®). A network using infrared rays may be used as the wireless network. A network using optical communication may be used as the wireless network. In this case, the control device 3 and the processing device 1 may be configured to enable the transmission and reception of various types of information via the network. The control device 3 may also be able to transmit information such as commands and control parameters to the processing device 1 via the network. The processing device 1 may be equipped with a receiving device that receives information such as commands and control parameters from the control device 3 via the network. The processing device 1 may be equipped with a transmitting device (i.e., an output device that outputs information to the control device 3) that transmits information such as commands and control parameters to the control device 3 via the network. The device comprising the processing device 1 and the control device 3 may be referred to as a processing system.

[0079] Alternatively, the control device 3 may be provided inside the processing apparatus 1. In other words, the processing apparatus 1 may be equipped with the control device 3. Alternatively, a first control device that performs some of the processing carried out by the control device 3 may be provided inside the processing apparatus 1, while a second control device that performs other parts of the processing carried out by the control device 3 may be provided outside the processing apparatus 1.

[0080] The control device 3 may implement a computational model that can be constructed by machine learning, which is achieved by the arithmetic unit 31 executing a computer program. An example of a computational model that can be constructed by machine learning is a computational model that includes a neural network (so-called artificial intelligence (AI)). In this case, the learning of the computational model may include learning the parameters of the neural network (for example, at least one of the weights and biases). The control device 3 may use the computational model to control the operation of the processing device 1. That is, the operation of controlling the operation of the processing device 1 may include the operation of controlling the operation of the processing device 1 using the computational model. The control device 3 may implement a computational model that has been constructed by offline machine learning using training data. Furthermore, the computational model implemented in the control device 3 may be updated by online machine learning on the control device 3. Alternatively, the control device 3 may use, in addition to or instead of, the computational model implemented in the control device 3 to control the operation of the processing device 1 using a computational model implemented in an external device (i.e., a device provided outside the processing device 1).

[0081] Furthermore, the recording medium for recording the computer program executed by the control device 3 may include at least one of the following: optical discs such as CD-ROM, CD-R, CD-RW, flexible disk, MO, DVD-ROM, DVD-RAM, DVD-R, DVD+R, DVD-RW, DVD+RW, and Blu-ray (registered trademark); magnetic media such as magnetic tape; magneto-optical disks; semiconductor memory such as USB memory; and any other medium capable of storing a program. The recording medium may also include equipment capable of recording computer programs (for example, general-purpose or dedicated equipment on which the computer program is implemented in a state in which it can be executed in at least one form such as software and firmware). Furthermore, each process and function included in the computer program may be implemented by logical processing blocks realized within the control device 3 (i.e., the computer) when the control device 3 executes the computer program, or it may be implemented in a form in which partial hardware modules that realize some elements, such as FPGAs (Field Programmable Gate Arrays) and ASICs (Application Specific Integrated Circuits), are mixed together in a predetermined gate array provided by the control device 3.

[0082] The control device 3 is configured to control the operation of the processing device 1. In other words, the control device 3 can control not only the light source 2 that outputs processing light EL, but also the beam scanning device 2 that irradiates the processing light EL, and the powder supply device 7 (blade B (material coating device 112), carrier moving device 113) that forms the material layer ML.

[0083] (2) The molding control device 3 of the processing device 1 receives CAD data of the three-dimensional structure to be fabricated from an external source into the arithmetic unit 31, which has read a program from the storage device 32. Before performing the operation to fabricate the structural layer SL, the control device 3 slices the three-dimensional model data at the layering pitch to create slice data. The control device 3 then controls the light source 4, beam scanning device 2, and powder supply device 7 to fabricate the three-dimensional structure ST by fabricating multiple structural layer SL on the carrier 111 and, consequently, on the build plate 114, based on the slice data. The processing device 1 fabricates the three-dimensional structure ST, so it may be called a fabrication device.

[0084] More specifically, the control device 3 uses the arithmetic unit 31, which has read a program from the storage device 32 based on slice data or CAD data, to generate carrier control information and output it to the powder supply device 7. The carrier control information is information for driving the carrier moving device 113 according to the slice pitch to form the material layer ML. The powder supply device 7, more specifically the carrier moving device 113, moves (descends) according to the carrier control information received from the control device 3 after the carrier 111, and thus the build plate 114, have been aligned to their initial positions, for example, with the build plate 114 at the height of the reference plane, in order to form the material layer ML. Then, by sequentially moving the blade B above the powder supply unit D, above the recess formed by the carrier 111 and the build cylinder 115, and above the powder recovery unit C, a material layer ML is formed on the build plate 114 according to the amount the build plate 114 (carrier 111) descends, i.e., the slice pitch. In this state, processing light EL is irradiated onto the material layer ML based on each slice data (light source control information, processing path information) to create the structural layer SL (details will be described later). After creating the structural layer SL, the blade B moves (descends) again to form the material layer ML based on the carrier control information received from the control device 3. Subsequently, the blade B is moved sequentially above the powder supply unit D, above the recess formed by the carrier 111 and the build cylinder 115, and above the powder recovery unit C, thereby forming the material layer ML on the build plate 114 according to the amount the build plate 114 (carrier 111) descends, i.e., the slice pitch. Prior to this movement, the blade B irradiates the material layer ML with processing light EL to create the structural layer SL, and before moving the blade B sequentially again from above the powder supply unit D to above the powder recovery unit C, it moves from above the powder recovery unit C to above the powder supply unit D. In this way, by repeatedly forming material layers ML, multiple structural layers SL can be fabricated on the build plate 114 to create a three-dimensional structure ST.

[0085] The control device 3 controls the light source 4 and the beam scanning device 2 to configure each of the multiple structural layers SL that make up the three-dimensional structure ST. In other words, the control device 3 uses the arithmetic unit 31, which has read a program from the storage device 32 based on slice data or CAD data, to generate light source control information and output it to the light source 4, and also generates processing path information and output it to the beam scanning device 2. The light source control information is information regarding the ON / OFF status and intensity of the processing light EL. The processing path information is information indicating the irradiation position of the processing light EL or the movement trajectory of the focal position of the processing light EL.

[0086] More specifically, with the material layer ML formed in the powder supply device 7 according to the slice pitch based on carrier control information, the light source 4 is controlled based on light source control information, and the beam scanning device 2 is controlled based on processing path information. Based on the light source control information, the light source 4 performs ON / OFF control and intensity control of the processing light EL.

[0087] Simultaneously with controlling the light source 4 based on this light source control information, the beam scanning device 2 deflects the processing light EL based on the processing path information so that the processing light EL is irradiated to the position indicated by the processing path information. In other words, based on the processing path information, the beam scanning device 2 drives the scanning mirror 231 and scanning mirror 232 with the actuator 233, deflecting the processing light EL with the scanning mirror 231 and scanning mirror 232, thereby scanning or sweeping the processing light EL on the surface of the material layer ML. Specifically, based on the processing path information, the beam scanning device 2 rotates the actuator 233 (first actuator) around a rotation axis extending along the X direction, thereby scanning or sweeping the processing light EL incident on the scanning mirror 231 in the Y direction where the material layer ML extends. Furthermore, the beam scanning device 2 rotates the actuator 233 (second actuator) around a rotation axis extending along the Y direction based on the processing path information, thereby scanning or sweeping the processing light EL incident on the scanning mirror 232 in the X direction where the material layer ML extends.

[0088] In this way, the processing light EL obtained by controlling the light source 4 based on the light source control information is scanned or swept in the XY plane where the material layer ML extends, by controlling the beam scanning device 2 based on the processing path information. As a result, the material layer ML is partially melted by the scanned or swept processing light EL. Subsequently, after the processing light EL no longer irradiates the melted material layer ML, the melted material layer ML solidifies. As a result, a structural layer SL corresponding to the solidified material layer ML, and consequently a three-dimensional structure ST consisting of multiple structural layers SL, is formed. The structural layer SL may be equivalent to a sintered layer formed by sintering the molding material M.

[0089] As described above, the beam scanning device 2 uses the scanning optical member 23 to scan or sweep the surface of the material layer ML with the processing light EL, that is, to move the irradiation area on the surface of the material layer ML to which the processing light EL is irradiated. In this case, if the focusing position of the processing light EL remains fixed, the state of the beam scanning device 2 will fluctuate between a first state in which the processing light EL is focused and irradiated onto the material layer ML, and a second state in which the processing light EL is defocused and irradiated onto the material layer ML, in accordance with the scanning optical member 23. Consequently, because the intensity of the defocused processing light EL on the surface of the uppermost material layer ML is different from the intensity of the focused processing light EL on the surface of the uppermost material layer ML, the intensity of the processing light EL on the surface of the material layer ML will fluctuate unintentionally in accordance with the scanning of the processing light EL by the scanning optical member 23. Such fluctuations in the intensity of the processing light EL can lead to a deterioration in the accuracy of the fabrication process. Furthermore, the term "focused state" may mean that the focusing position of the processing light EL is located on the surface of the uppermost material layer ML (or in the vicinity of the surface of the uppermost material layer ML). Conversely, the term "defocused state" may mean that the focusing position of the processing light EL is located a certain distance or more away from the surface of the uppermost material layer ML (or in the vicinity of the surface of the uppermost material layer ML).

[0090] Therefore, the beam scanning device 2 may change the focusing position and spot size of the processing light EL in accordance with the scanning optical member 23 so that the focusing position of the processing light EL is located on the surface of the uppermost material layer ML (or near the surface of the uppermost material layer ML), and the spot size of the processing light EL is a desired size. Specifically, the beam scanning device 2 may generate a control signal using the arithmetic unit 31 which has read a program from the storage device 32 based on slice data or CAD data, and move at least one of the movable lens 2111 using actuator 2141 and at least one of the movable lens 2121 using actuator 2142 to change at least one of the focusing position and spot size of the processing light EL. Note that the spot size of the processing light EL may mean the size of the beam spot formed by the processing light EL on the surface of the object (e.g., material layer ML) that is irradiated with the processing light EL. In other words, the spot size of the processing light (EL) may refer to the size of the irradiation area (i.e., the beam spot) on the surface of an object (e.g., a material layer ML) where the processing light (EL) is irradiated.

[0091] In this embodiment, the beam scanning device 2 may change the focusing position and spot size of the processing light EL by moving the movable lenses 2111 and 2121 using actuators 2141 and 2142 under the control of the control device 3. For example, the beam scanning device 2 may change the focusing position and spot size of the processing light EL simultaneously by moving the movable lenses 2111 and 2121 at the same time. For example, the beam scanning device 2 may change the focusing position and spot size of the processing light EL synchronously by moving the movable lenses 2111 and 2121 in synchronous order. For example, the beam scanning device 2 may change the focusing position and spot size of the processing light EL by moving one of the movable lenses 2111 and 2121 and then moving the other of the movable lenses 2111 and 2121.

[0092] As a result, the possibility of unintended fluctuations in the intensity of the processing light EL on the surface of the material layer ML in accordance with the scanning of the processing light EL by the scanning optical element 23 is low. Consequently, the processing apparatus 1 can fabricate three-dimensional structures with high fabrication accuracy.

[0093] It should be noted that the fabrication process does not necessarily have to be performed using a focused processing light EL. When fabrication is performed using a defocused processing light EL, the beam scanning device 2 may be controlled so that the focusing position of the processing light EL is located on a surface that is defocused from the surface of the uppermost material layer ML during scanning of the processing light EL by the scanning optical member 23.

[0094] The beam scanning device 2 may change the focusing position and spot size of the processing light EL so that the spot size of the processing light EL remains constant even when the focusing position of the processing light EL is changed. Specifically, fluctuations in the spot size of the processing light EL on the surface of the material layer ML lead to fluctuations in the intensity of the processing light EL on the surface of the material layer ML. This is because the larger the spot size, the smaller the intensity of the processing light EL per unit area (i.e., the influence of the processing light EL). Therefore, the beam scanning device 2 may change the focusing position and spot size of the processing light EL so that the focusing position of the processing light EL is located on the surface of the uppermost material layer ML (or near the surface of the uppermost material layer ML) and the spot size of the processing light EL remains constant, in accordance with the scanning of the processing light EL by the scanning optical member 23. As a result, the possibility of unintended fluctuations in the intensity of the processing light EL on the surface of the material layer ML in accordance with the scanning of the processing light EL by the scanning optical member 23 is low. As a result, the processing device 1 can fabricate three-dimensional structures with high fabrication accuracy.

[0095] Furthermore, the observation light OL may be received by the light receiving device 24, and the status of the three-dimensional structure being formed by the processing device 1 may be observed (in other words, monitored). Preferably, the control device 3 controls the processing device 1 to appropriately form the three-dimensional structure based on the observation results (in other words, monitoring results) of the status of the three-dimensional structure being formed by the processing device 1.

[0096] The control device 3 controls the light source 4 and the beam scanning device 2 based on the information received from the output unit 24b of the light receiving device 24. For example, if the brightness information received from the output unit 24b is higher than a threshold, the control device 3 considers that the temperature of the melted portion of the material layer ML, the so-called melt pool, is high. Also, if the size of the light-emitting portion detected from the information received from the output unit 24b is larger than a threshold, it is considered that the size of the melted portion of the material layer ML, the so-called melt pool, is large. In these cases, if the brightness information is higher than a threshold, the control device 3 controls the light source 4 and the beam scanning device 2 so as to reduce the amount of energy per unit area that the processing light EL imparts to the material layer ML. In other words, the control device 3 controls the light source 4 so as to reduce the output (intensity) of the processing light EL, or, if the processing light EL is pulsed light, so as to reduce the repetition frequency. In addition, the control device 3 controls the beam scanning device 2, more specifically the scanning optical element 23, to increase the scanning speed of the processing light EL. As a result, the processing system SYS, and by extension the processing device 1, can perform additive processing appropriately and create three-dimensional structures.

[0097] (3) Modifications In the embodiments described above, a processing apparatus 1 equipped with a single beam scanning device 2 has been described, but it is not limited to this. For example, the processing apparatus 1 may be equipped with a plurality of beam scanning devices 2.

[0098] In this modified example, the processing apparatus 1 is equipped with multiple beam scanning devices 2, allowing additive processing to be performed using multiple processing light ELs. Therefore, the throughput of additive processing is improved compared to the case where additive processing is performed using a single processing light EL. For example, the time required to fabricate a three-dimensional structure is reduced.

[0099] For example, the modified processing apparatus 1, as shown in Figure 4, includes a group of beam scanning devices 2', which comprises six beam scanning devices 2#1 to 2#6 arranged on the same plane (XY plane). Each of the beam scanning devices 2#1 to 2#6 has the same configuration as the beam scanning device 2 of the first embodiment. Of the group of beam scanning devices 2', beam scanning devices 2#1 to 2#3, i.e., the first beam scanning units, are arranged in a line along the X direction. Similarly, of the group of beam scanning devices 2', beam scanning devices 2#4 to 2#6, i.e., the second beam scanning units, are arranged in a line along the X direction. The first beam scanning units and the second beam scanning units are arranged in the Y direction. In this way, the six beam scanning devices 2 are regularly arranged at the grid points (intersections) of a grid defined by the axes extending in the respective extension directions of the first and second beam scanning units and the axes extending in the alignment direction of the first and second beam scanning units. In this modified example, multiple beam scanning devices 2 are arranged in a configuration of three in the X direction and two in the Y direction. However, the arrangement is not limited to this configuration, and the number of devices in the X and Y directions may be adjusted as appropriate. In addition, in the Y direction, beam scanning device 2#4 is not necessarily located next to beam scanning device 2#1, beam scanning device 2#5 is not necessarily located next to beam scanning device 2#, and beam scanning device 2#6 is not necessarily located next to beam scanning device 2#3.

[0100] In addition, as shown in Figure 5, beam scanning devices 2#1 to 2#6 may be positioned at equidistant locations from the reference point, such that when lines are drawn connecting the reference point and each beam scanning device 2, the angles formed by these adjacent lines are the same.

[0101] Furthermore, each of the beam scanning devices 2#1 to 2#6 receives the processing light EL via the optical fiber 5. The processing light EL that is incident on each of the beam scanning devices 2#1 to 2#6 has multiple (six) light sources 4 (4-1 to 4-6) that supply the processing light EL to each of the beam scanning devices 2#1 to 2#6.

[0102] Alternatively, the processing light EL emitted from each of the beam scanning devices 2#1 to 2#6 may be irradiated onto the material layer ML through a single aperture 251 provided in the housing 25, and consequently through a single optical window 2510 provided in the aperture 251. In addition, the processing light EL emitted from each of the beam scanning devices 2#1 to 2#6 may be irradiated onto the material layer ML through multiple apertures 251 in the housing 25, and consequently through multiple optical windows 2510 provided in these multiple apertures 251, corresponding to each of the beam scanning devices 2#1 to 2#6.

[0103] In the modified processing apparatus 1, the control device 3 controls the beam scanning devices 2#1 to 2#6 and the light sources 4-1 to 4-6 corresponding to each of the beam scanning devices 2#1 to 2#6. Specifically, the control device 3 receives information regarding the processing area of ​​each beam scanning device 2#1 to 2#6 according to the number and arrangement of the beam scanning devices 2, or determines the processing area of ​​each beam scanning device 2#1 to 2#6 according to the number and arrangement of the beam scanning devices 2. Based on slice data or CAD data, the control device 3 generates processing path information for each processing area of ​​each beam scanning device 2#1 to 2#6, and consequently for each beam scanning device 2#1 to 2#6. In addition, the control device 3 generates light source control information to control each light source 4-1 to 4-6 along with this processing path information for each beam scanning device 2#1 to 2#6.

[0104] The processing apparatus 1 may irradiate at least a portion of the material layer ML formed on the carrier 111 with multiple processing light ELs emitted from beam scanning devices 2#1 to 2#6, respectively. In particular, the processing apparatus 1 may simultaneously irradiate at least a portion of the material layer ML with multiple processing light ELs. That is, the processing apparatus 1 may simultaneously scan at least a portion of the material layer ML with multiple processing light ELs. In this case, the processing area of ​​one beam scanning device 2, i.e., the area scanned by one processing light EL, and the processing area of ​​another beam scanning device 2, i.e., the area scanned by another processing light EL different from the first processing light EL, may partially overlap.

[0105] (4) Other Modifications As shown in Figure 6, an additional light-receiving element and intensity detection element 29 capable of receiving processed light EL may be provided. A portion of the processed light EL is incident on the intensity detection element 29, and the intensity of the processed light EL incident on the intensity detection element 29 is detected. For example, an image sensor such as a CMOS or CCD can be used for the intensity detection element 29. In this case, as the reflective mirror 2131, an optical member such as a half mirror is used that reflects a portion of the incident processed light EL to the reflective mirror 2132 and transmits a portion, and the light transmitted through the reflective mirror 2131 is incident on the intensity detection element 29. When the light is incident from the reflective mirror 2131 to the intensity detection element 29, an opening 254 may be provided in the housing 25, an optical window 2540 may be placed in the opening 254 provided in the housing 25, or a mirror 30 may be provided to bend the optical path.

[0106] The intensity detection element 29 may also be called an intensity detector (or sensor), a power detector (or sensor), an energy detector (or sensor), or a power meter. Furthermore, the intensity detection element 29 may be a detector that monitors the power distribution or beam cross-sectional shape of the incident processing light EL.

[0107] The configuration of the processing apparatus 1 shown in Figure 1 is merely an example. Therefore, the processing apparatus 1 may have a configuration different from that shown in Figure 1. For example, the processing apparatus 1 may have any configuration as long as it includes a beam scanning device 2 (including modified versions thereof). For example, the processing apparatus 1 may have any configuration as long as it can perform additional processing using processing light EL from the beam scanning device 2 (including modified versions thereof).

[0108] For example, the processing apparatus 1 may include a processing head that is movable by a manipulator. Here, the manipulator may move the processing head in one or more of the three directions X, Y, and Z and the three (rotational) directions θx, θy, and θz. The processing head may include one or more beam scanning devices 2. In this case, the processing apparatus 1 may move one or more beam scanning devices 2 by a manipulator. The processing apparatus 1 may also include one or more shielding members that cover the optical path of the processing light EL from the beam scanning devices 2. At least a part of this one or more shielding members may be moved by a manipulator. In this case, at least a part of the shielding member and the beam scanning device 2 may be moved together. The shielding member may also include a gas input port and / or a gas output port for forming a gas flow in the space enclosed by the shielding member. The processing head may optionally include a material coating device and a recoater. Such a processing apparatus can perform additional processing on workpieces that are larger than the size of the processing apparatus, typically the size of the shielding member, or can fabricate objects that are larger than the size of the process chamber.

[0109] The light-transmitting members such as optical windows and lenses described above may also be reflective members. Furthermore, the reflective members such as mirrors described above may also be light-transmitting members.

[0110] In the above description, the processing apparatus 1 melts the material layer ML by irradiating it with processing light EL. However, the processing apparatus 1 may also melt the material layer ML by irradiating it with any energy beam. Examples of energy beams include at least one of a charged particle beam and an electromagnetic wave. Examples of charged particle beams include at least one of an electron beam and an ion beam.

[0111] In the above description, the processing apparatus 1 performs additive processing using processing light EL emitted from the beam scanning device 2. However, the processing apparatus 1 may also perform removal processing using processing light EL emitted from the beam scanning device 2. For example, the processing apparatus 1 may perform removal processing by irradiating the workpiece with processing light EL emitted from the beam scanning device 2 to remove a portion of the workpiece.

[0112] The processing apparatus 1 may perform a remelt process in addition to at least one of the additive process and the removal process. The remelt process may include a process to reduce the flatness of the surface of an object processed by at least one of the additive process and the removal process (for example, a three-dimensional structure formed by the additive process or a workpiece from which a portion has been removed by the removal process). Reducing the flatness of the surface of an object may be equivalent to at least one of reducing the surface roughness of the surface of the object and making the surface of the object closer to a plane.

[0113] (5) Detection process As described above, in the processing apparatus 1, the molding material M is melted by the processing light EL, and then the molten molding material M solidifies to form a molded object (for example, a three-dimensional structure ST). For example, during the molding of a molded object, spatter (i.e., splatter) of the molten molding material M may occur due to the irradiation of the molding material M with the processing light EL. If spatter occurs, there is a risk that the spatter will remain as foreign matter on the surface of the material layer ML in the chamber space SP120, that is, within the molding area. In other words, if spatter occurs, there is a risk that defective products will be molded.

[0114] For example, in light of the above circumstances, in this embodiment, a detection process is performed to detect abnormalities that occur during the fabrication of the object. In the following, abnormalities will be described as including anomalies and changes. Note that the abnormalities to be detected are not limited to the sputtering described above. Specific examples of abnormalities to be detected will be described later.

[0115] The detection process performed by the control device 3 will be described below with reference to Figures 7 to 11. The detection process may be performed after the nth structural layer, which constitutes a part of the fabricated object (for example, a three-dimensional structure ST), has been fabricated by the processing device 1, but before the (n+1)th structural layer, which constitutes another part of the fabricated object, has been fabricated. For example, the control device 3 may, after controlling the processing device 1 to fabricate the nth structural layer, interrupt the fabrication process and perform the detection process. If no abnormality is detected during the detection process, the control device 3 may resume the fabrication process.

[0116] In the flowchart of Figure 7, the arithmetic unit 31 of the control device 3 acquires measurement information from the measuring device 8 regarding the surface of the molding material M stored in the recess (see Figure 2) formed by the carrier 111 and the build cylinder 115 (the measurement information is input from the measuring device 8 to the arithmetic unit 31 of the control device 3) (step S101). The measurement information may correspond to the shape data described above. In other words, the measurement information may be shape data that shows the three-dimensional shape of the surface of the molding material M. An example of shape data is at least one of point cloud data and depth image data. Point cloud data and depth image data are data that shows the position (i.e., coordinates) of each of multiple parts of the measurement target (e.g., the surface of the molding material M) in a three-dimensional coordinate space. Therefore, acquiring measurement information can be rephrased as acquiring three-dimensional position data. If the measurement information is point cloud data, the measuring device 8 may generate a file with the extension .asc or .csv as the measurement information.

[0117] The measurement information acquired by the arithmetic unit 31 in step S101 may be measurement information generated by the measuring device 8 measuring the state of the surface of the molding material M after it has been smoothed by the blade B (see Figure 2) and before the processing light EL is irradiated onto the surface of the molding material M.

[0118] The measurement information acquired from the measuring device 8 may be represented in the measurement coordinate system, which is the coordinate system related to the measuring device 8. The control device 3 may control the beam scanning device 2 based on information (e.g., processing path information) represented in the processing coordinate system, which is the coordinate system related to the processing device 1 (e.g., beam scanning device 2). In this case, if the coordinate system related to the measurement information and the coordinate system for controlling the beam scanning device 2 are different, the calculation device 31 may perform a coordinate transformation process on the measurement information represented in the measurement coordinate system to convert between the measurement coordinate system and the processing coordinate system, thereby generating measurement information represented in the processing coordinate system. However, the calculation device 31 does not have to generate measurement information represented in the processing coordinate system.

[0119] After the processing in step S101, the calculation unit 31 generates two-dimensional height distribution data based on the measurement information (step S102). In this embodiment, as shown in Figure 2, the surface (in other words, the top surface) of the molding material M stored in the recess formed by the carrier 111 and the build cylinder 115 is a surface that aligns with the XY plane. For example, the calculation unit 31 may generate two-dimensional height distribution data by assigning the Z coordinate value (in other words, height information) included in the measurement information to each element of a two-dimensional matrix represented by two coordinate axes, the X axis and the Y axis, which corresponds to a surface that aligns with the XY plane. Therefore, the two-dimensional height distribution data can be said to be two-dimensional data relating to height information corresponding to each position (or each region) on a surface that aligns with the XY plane.

[0120] For example, the arithmetic unit 31 may assign the Z coordinate values ​​included in the measurement information to each element of the two-dimensional matrix TDM shown in Figure 8. The number of elements in the two-dimensional matrix TDM (in other words, the size of the two-dimensional matrix) may be predetermined. That is, the arithmetic unit 31 may assign the Z coordinate values ​​included in the measurement information to each element of the predetermined two-dimensional matrix TDM. Here, the X and Y coordinate values ​​of the multiple three-dimensional coordinates representing multiple points included in the point cloud data as measurement information are irregular (in other words, the X and Y coordinate values ​​are not arranged in a regular pattern). For this reason, two or more points included in the point cloud data may correspond to element aij of the two-dimensional matrix TDM. In this case, the arithmetic unit 31 may assign the maximum Z coordinate value of the two or more points corresponding to element aij to element aij.

[0121] The arithmetic unit 31 may, after assigning the Z coordinate values ​​included in the measurement information to each element of the two-dimensional matrix TDM, adjust the values ​​of each element of the two-dimensional matrix TDM. For example, the arithmetic unit 31 may calculate the average value of each element of the two-dimensional matrix TDM. The arithmetic unit 31 may then use the difference between the calculated average value and the value of each element as the new value of each element. In this case, the average value of the new values ​​of each element of the two-dimensional matrix TDM will be 0. For example, the arithmetic unit 31 may calculate the least-squares plane based on the values ​​of each element of the two-dimensional matrix TDM. The arithmetic unit 31 may then use the difference between the calculated least-squares plane and the value of each element as the new value of each element.

[0122] In this way, the arithmetic unit 31 generates two-dimensional height distribution data based on measurement information, thereby generating data in which the X and Y coordinate values ​​are arranged in a regular pattern. Two-dimensional height distribution data, in which the X and Y coordinate values ​​are arranged in a regular pattern, can be handled in the same way as image data. For example, the arithmetic unit 31 may generate a file with the extension .tif as the two-dimensional height distribution data.

[0123] The arithmetic unit 31 may perform noise reduction processing on the generated two-dimensional height distribution data. As described above, the two-dimensional height distribution data can be handled in the same way as image data, so the arithmetic unit 31 may perform median filtering as noise reduction processing.

[0124] After step S102 in Figure 7, the arithmetic unit 31 generates a binarized image based on the two-dimensional height distribution data (step S103). For example, the arithmetic unit 31 may generate a binarized image by binarizing the height of each position (or each region) of a plane along the XY plane indicated by the two-dimensional height distribution data, based on a predetermined threshold.

[0125] For example, the arithmetic unit 31 may generate a first binarized image from two-dimensional height distribution data using a first threshold. Here, the first threshold may be a positive value. For example, the arithmetic unit 31 may generate image Img1 shown in Figure 9 as the first binarized image. The white areas in image Img1 correspond to elements in the two-dimensional height distribution data that have a value greater than the first threshold. In other words, the white areas in image Img1 correspond to parts of the surface of the molding material M that protrude in the +Z direction (see Figure 2).

[0126] For example, the arithmetic unit 31 may generate a second binarized image from the two-dimensional height distribution data using a second threshold value. Here, the second threshold value is smaller than the first threshold value. The second threshold value may also be negative. For example, the arithmetic unit 31 may generate image Img2 shown in Figure 10 as the second binarized image. The black areas in image Img2 correspond to elements in the two-dimensional height distribution data that have a value smaller than the second threshold value. In other words, the black areas in image Img2 correspond to parts of the surface of the molding material M that are indented in the -Z direction (see Figure 2).

[0127] In the process of step S103, the arithmetic unit 31 may generate a first binarized image and a second binarized image as binarized images. The arithmetic unit 31 may generate only one of the first binarized image and the second binarized image as binarized images. The arithmetic unit 31 may also generate, for example, a ternary image instead of a binarized image. In other words, the arithmetic unit 31 may generate a multi-level image to the extent that it can identify at least one of the parts of the surface of the molding material M that protrude in the +Z direction and the parts that are recessed in the -Z direction.

[0128] After the processing in step S103, the arithmetic unit 31 performs a predetermined region extraction process on the binarized image (for example, at least one of the first binarized image and the second binarized image). The arithmetic unit 31 then determines whether or not a region has been extracted (step S104). Here, the region extracted by the predetermined region extraction process is a region corresponding to at least one of the parts of the surface of the molding material M that protrude in the +Z direction and the parts that are recessed in the -Z direction. In this embodiment, as described above, the binarized image used is an image generated by binarizing the height of each position (or each region) of a surface along the XY plane indicated by two-dimensional height distribution data. However, the binarized image may also be generated by binarizing parameters correlated with the height of each position (or each region) of a surface along the XY plane.

[0129] Specifically, regions Ar1, Ar2, and Ar3 containing the white areas in image Img1 (see Figure 9), an example of a first binarized image, may be extracted by a predetermined region extraction process. Similarly, regions Ar4 and Ar5 containing the black areas in image Img2 (see Figure 10), an example of a second binarized image, may be extracted by a predetermined region extraction process. The predetermined region extraction process may be a process using OpenCV. In this case, the extracted regions may correspond to regions enclosed by bounding boxes. The extracted regions are regions included in the binarized image. The binarized image is an image generated based on two-dimensional height distribution data and predetermined thresholds (for example, at least one of a first threshold and a second threshold). Therefore, the extracted regions can be said to be regions extracted from the two-dimensional height distribution data using predetermined thresholds.

[0130] If it is determined that no region is extracted during the process in step S104 (step S104: No), the operation shown in Figure 7 (i.e., the detection process) is terminated. The detection process may be repeated once or multiple times during the recoating operation in which the surface of the molding material M is smoothed by the blade B, from the start of molding of the molded object until the end of molding of the molded object.

[0131] If it is determined that an area has been detected in step S104 (step S104: Yes), the arithmetic unit 31 performs a classification process (step S20). The classification process will be explained with reference to the flowchart in Figure 11. The classification process is a process for classifying abnormalities that appear on the surface of the molding material M.

[0132] Specific examples of abnormalities are described below. Specific examples of abnormalities include spatter, raised parts of the printed object (i.e., a part of the printed object protruding from the surface of the printing material M), recoater hopping (i.e., the blade B (see Figure 2) bouncing in the Z direction on the surface of the printing material M), scratches, and insufficient supply of the printing material M. At least one of spatter (especially relatively large spatter) and raised parts of the printed object is likely to interfere with the blade B and may cause recoater hopping. During the printing of an object, a part of the printed object may peel off. For example, the blade B may drag a metal fragment from the peeled-off part and at least one of the spatter, causing scratches on the surface of the printing material M. If there is insufficient printing material M supplied to the recess (see Figure 2) formed by the carrier 111 and the build cylinder 115, depressions may occur on the surface of the printing material M.

[0133] In Figure 11, the arithmetic unit 31 of the control device 3 determines whether the extracted region corresponds to a convex portion (step S201). For example, the region extracted from the first binarized image can be said to be a region corresponding to a convex portion. On the other hand, the region extracted from the second binarized image can be said to be a region corresponding to a concave portion.

[0134] In step S201, if it is determined that the extracted region corresponds to a convex portion (step S201: Yes), the arithmetic unit 31 determines whether the area of ​​the region (i.e., the region corresponding to the convex portion) is greater than a predetermined area a (step S202). In step S202, if it is determined that the area of ​​the region is not greater than the predetermined area a (step S202: No), the arithmetic unit 31 classifies the extracted region as a region caused by large sputtering (step S204). The information indicating the predetermined area a may be stored in advance in the storage device 32 of the control device 3.

[0135] In step S202, if it is determined that the area of ​​the region is larger than a predetermined area a (step S202: Yes), the arithmetic unit 31 determines whether the value x in the X-axis direction of the aspect ratio between the length of the region in the X-axis direction and the length of the region in the Y-axis direction is significantly larger than the value y in the Y-axis direction (step S203). In step S203, if it is determined that the value x is significantly larger than the value y (step S203: Yes), the arithmetic unit 31 classifies the extracted region as a region caused by recoater hopping (step S205). For example, the arithmetic unit 31 may determine that the value x is significantly larger than the value y if the value obtained by dividing the value x by the value y is greater than a first predetermined value. The first predetermined value may be stored in advance in the storage device 32 of the control device 3.

[0136] In this embodiment, blade B (see Figure 2) is a member that extends along the X-axis direction. Blade B moves along the Y-axis direction on the surface of the molding material M. When recoater hopping occurs in the processing apparatus 1 according to this embodiment, the trace of blade B, which extends along the X-axis direction, remains on the surface of the molding material M. Therefore, in step S203, it is determined whether the value x in the X-axis direction of the aspect ratio is significantly larger than the value y in the Y-axis direction. Blade B may be a member that extends along the Y-axis direction, and blade B may move along the X-axis direction on the surface of the molding material M. In this case, in step S203, it is determined whether the value y in the Y-axis direction of the aspect ratio is significantly larger than the value x in the X-axis direction.

[0137] In the process of step S203, if it is determined that the value x is not significantly larger than the value y (step S203: No), the calculation unit 31 classifies the extracted region into a region caused by the protrusion of the molded object (step S206).

[0138] In step S201, if it is determined that the extracted region is not a region corresponding to a convex portion (step S201: No), the arithmetic unit 31 determines whether the value y in the Y-axis direction of the aspect ratio between the length of the region in the Y-axis direction and the length of the region in the X-axis direction is significantly larger than the value x in the X-axis direction (step S207). In step S207, if it is determined that the value y is significantly larger than the value x (step S207: Yes), the arithmetic unit 31 classifies the extracted region as a region caused by a scratch (step S208). For example, the arithmetic unit 31 may determine that the value y is significantly larger than the value x if the value obtained by dividing the value y by the value x is greater than a second predetermined value. The second predetermined value may be stored in advance in the storage device 32 of the control device 3. The second predetermined value may be different from or the same as the first predetermined value.

[0139] As described above, in this embodiment, the blade B moves along the Y-axis direction on the surface of the molding material M. As described above, scratches may occur on the surface of the molding material M due to the blade B dragging the metal piece. Since the metal piece is dragged by the blade B moving along the Y-axis direction, the scratches will extend in the Y-axis direction. For this reason, in step S207, it is determined whether the value y in the Y-axis direction of the aspect ratio is significantly larger than the value x in the X-axis direction. The blade B may move along the X-axis direction on the surface of the molding material M. In this case, in step S207, it is determined whether the value x in the X-axis direction of the aspect ratio is significantly larger than the value y in the Y-axis direction.

[0140] In the process of step S207, if it is determined that the value y is not significantly larger than the value x (step S207: No), the calculation unit 31 classifies the extracted region into a region caused by a shortage of powdered molding material M (step S209).

[0141] The arithmetic unit 31 performs the classification process described above for all extracted regions. In other words, the arithmetic unit 31 repeats the classification process described above until the classification of all extracted regions is completed. The arithmetic unit 31 may also perform the classification process described above using an arithmetic model (i.e., an arithmetic model that can be constructed by machine learning) that outputs a classification result when it receives an image representing a region extracted from a binarized image as input.

[0142] For example, region Ar1 in image Img1 shown in Figure 9 is a region corresponding to a convex part. The area of ​​region Ar1 is assumed to be smaller than a predetermined area a. In this case, the arithmetic unit 31 determines in step S201 that region Ar1 is a region corresponding to a convex part (step S201: Yes), and in step S202 that the area of ​​region Ar1 is not larger than the predetermined area a (step S202: No). As a result, the arithmetic unit 31 may classify region Ar1 as a region caused by large sputtering.

[0143] For example, region Ar2 in the image Img1 shown in Figure 9 is a region corresponding to a convex part. The area of ​​region Ar2 is assumed to be larger than a predetermined area a. In this case, the arithmetic unit 31 may determine in step S201 that region Ar2 is a region corresponding to a convex part (step S201: Yes), in step S202 that the area of ​​region Ar2 is larger than a predetermined area a (step S202: Yes), and in step S203 that the value x in the X-axis direction of the aspect ratio of region Ar2 is significantly larger than the value y in the Y-axis direction (step S203: Yes). As a result, the arithmetic unit 31 may classify region Ar2 as a region caused by recoater hopping.

[0144] For example, region Ar3 in image Img1 shown in Figure 9 is a region corresponding to a convex part. The area of ​​region Ar3 is assumed to be larger than a predetermined area a. In this case, the arithmetic unit 31 may determine in step S201 that region Ar3 is a region corresponding to a convex part (step S201: Yes), in step S202 that the area of ​​region Ar3 is larger than a predetermined area a (step S202: Yes), and in step S203 that the value x in the X-axis direction of the aspect ratio of region Ar3 is not significantly larger than the value y in the Y-axis direction (step S203: No). As a result, the arithmetic unit 31 may classify region Ar3 as a region caused by a protrusion in the fabricated object.

[0145] For example, region Ar4 in the image Img2 shown in Figure 10 is a region corresponding to a recess. In this case, the arithmetic unit 31 may determine in step S201 that region Ar4 is not a region corresponding to a convex portion (step S201: No), and in step S207, it may determine that the value y in the Y-axis direction of the aspect ratio of region Ar4 is not significantly larger than the value x in the X-axis direction (step S207: No). As a result, the arithmetic unit 31 may classify region Ar4 as a region caused by a shortage of powdered molding material M.

[0146] For example, region Ar5 in the image Img2 shown in Figure 10 is a region corresponding to a recess. In this case, the arithmetic unit 31 may determine in step S201 that region Ar5 is not a region corresponding to a convex portion (step S201: No), and in step S207, it may determine that the value y in the Y-axis direction of the aspect ratio of region Ar5 is significantly larger than the value x in the X-axis direction (step S207: Yes). As a result, the arithmetic unit 31 may classify region Ar5 as a region caused by a scratch.

[0147] The detection process described above is performed using measurement information regarding the surface of the molding material M. Therefore, the detection process can be rephrased as determining the surface state of the molding material M. In the classification process described above, regions are classified (in other words, abnormalities are identified) based on at least one of the area and aspect ratio of the regions extracted from the binarized image. Therefore, classifying the regions extracted from the binarized image can be rephrased as classifying (or identifying) patterns represented by at least one of the area and aspect ratio. Furthermore, detecting abnormalities can be rephrased as detecting patterns that appear on the surface of the molding material M.

[0148] As shown in Figure 11, in the classification process, regions extracted from the binarized image are classified using predetermined conditions (see S201, S202, S203, and S207). Therefore, in the classification process, it can be said that the region extracted from the binarized image (i.e., a pattern) is identified as belonging to one of a predetermined set of patterns. For example, a predetermined area a, a first predetermined value, and a second predetermined value (i.e., the values ​​used for the determinations in S202, S203, and S207) may be stored in the storage device 32. In this case, the classification process can be said to be performed based on the information read from the storage device 32.

[0149] (6) Notification Processing When the classification process shown in Figure 11 is performed, the control device 3 may notify the user of the processing system SYS that an abnormality has been detected. In this case, in addition to outputting information that an abnormality has been detected and the detected abnormality, the control device 3 may also notify the user of the processing system SYS of the result of the classification process (in other words, the type of abnormality). Notifying the user of the result of the classification process can be rephrased as notifying the user of the type of pattern detected from the surface of the molding material M.

[0150] Herein, the present inventor's research has revealed the following: If bumps occur in the printed object, the user of the SYS processing system needs to take action. In this case, the user's action may include reprinting the object, rewriting the printing recipe, etc. Also, if large spatter occurs, the user of the SYS processing system needs to take action. In this case, the user's action may include removing the large spatter, adjusting the processing light EL, etc. Recoater hopping and scratches are often caused by at least one of bumps in the printed object and large spatter. Therefore, it is believed that recoater hopping and scratches will also be resolved if the user of the SYS processing system takes action to address at least one of the bumps in the printed object and large spatter. On the other hand, a shortage of printing material M will be resolved if printing material M is supplied. In other words, if a shortage of printing material M is detected as an abnormality, no action is required from the user of the SYS processing system.

[0151] In view of the above, the control device 3 according to this embodiment may perform the notification process described below. In the flowchart of Figure 12, the arithmetic unit 31 of the control device 3 determines whether the extracted region is a region caused by bulging of the molded object or a region caused by large sputtering (step S301). If, in the process of step S301, it is determined that the extracted region is a region caused by bulging of the molded object or a region caused by large sputtering (step S301: Yes), the arithmetic unit 31 issues an alarm (step S302). In this case, the arithmetic unit 31 may control the processing device 1 so that the molding of the molded object is temporarily suspended. The arithmetic unit 31 may also display the type of abnormality and the method of responding to the abnormality on a display (not shown).

[0152] In step S301, if it is determined that the extracted region is neither a region caused by a bulge in the molded object nor a region caused by excessive sputtering (step S301: No), the calculation unit 31 controls the powder supply device 7 to perform a recoat operation (step S303). In the recoat operation, the molding material M stored in the powder supply unit D (see Figure 2) is spread into the recess formed by the carrier 111 and the build cylinder 115, and the surface of the molding material M is smoothed by the blade B. In step S303, the control device 3 outputs control information to the powder supply device 7 to cause it to perform the recoat operation. Therefore, in the operation shown in Figure 12, it can be said that the control device 3 (specifically, the calculation unit 31) outputs control information to the powder supply device 7 in order to selectively perform the recoat operation according to the type of abnormality (in other words, pattern).

[0153] Subsequently, the arithmetic unit 31 performs the detection process shown in the flowchart of Figure 7 (step S304). Next, the arithmetic unit 31 determines whether or not an abnormality has been detected in the detection process (step S305). The arithmetic unit 31 may determine that an abnormality has been detected if it determines that an area has been detected in the process of step S104 in the flowchart of Figure 7.

[0154] In step S305, if the detection process determines that an abnormality has been detected (step S305: Yes), the calculation unit 31 issues an alarm (step S302). In this case, the calculation unit 31 issues an alarm regardless of the type of abnormality detected. As described above, it is believed that recoater hopping and scratches can be eliminated by the user of the processing system SYS addressing at least one of the raised areas and large spatter on the molded object. Also, a shortage of molding material M can be resolved by supplying molding material M. Following this idea, if an abnormality is detected in step S303 despite the recoating operation being performed, there is a possibility that some malfunction has occurred in the processing device 1 (for example, blade B). For this reason, if the detection process determines that an abnormality has been detected in step S305, the calculation unit 31 issues an alarm regardless of the type of abnormality.

[0155] In the process of step S305, if it is determined that no abnormality is detected in the detection process (step S305: No), the arithmetic unit 31 may perform the process for creating the object.

[0156] At least some of the constituent elements of each embodiment described above can be appropriately combined with at least some other constituent elements of each embodiment described above. Some of the constituent elements of each embodiment described above may not be used. Furthermore, to the extent permitted by law, all of the published patents and U.S. patent disclosures cited in each embodiment described above shall be incorporated into the text.

[0157] The present invention is not limited to the embodiments described above, and can be modified as appropriate without contradicting the gist or idea of ​​the invention as can be read from the claims and specification as a whole. Determination methods and molding apparatuses that involve such modifications are also included in the technical scope of the present invention.

[0158] 1 Processing device 111 Carrier 112 Material coating device 114 Build plate 2 Beam scanning device 21 Focusing optical system 2111, 2121 Movable lenses 2112, 2122 Fixed lenses 2131, 2132 Reflecting mirrors 2141, 2142 Actuator 22 Beam branching member 23 Scanning optical member 24 Light receiving device 25 Housing 3 Control device 31 Calculation unit 32 Memory device 4 Light source 5 Optical fiber 7 Powder supply device ML Material layer SL Structural layer SYS Processing system EL Processing light

Claims

1. A determination method used in a molding apparatus that melts a powdered molding material by irradiating it with an energy beam and forms a three-dimensional object with the molding material, the determination method comprising: acquiring measurement information relating to the surface of the molding material; and determining the surface state of the surface using height information included in the measurement information.

2. The determination method according to claim 1, wherein determining the surface state is further determined based on at least one of the area and aspect ratio of a portion of the surface identified based on height information.

3. The determination method according to claim 1 or 2, wherein the surface state is the state after the surface of the molding material has been leveled and before the energy beam is irradiated onto the surface of the material.

4. The determination method according to any one of claims 1 to 3, wherein determining the surface state includes generating two-dimensional data relating to height information corresponding to the position using the measurement information, and the region is a region extracted from the two-dimensional data.

5. The determination method according to claim 4, wherein generating the two-dimensional data is to generate two-dimensional height distribution data by assigning height information contained in the measurement information to each element of a predetermined two-dimensional matrix.

6. The determination method according to claim 5, wherein the region is a region extracted from the two-dimensional height distribution data using a threshold.

7. The determination method according to claim 4, wherein generating the two-dimensional data is to generate a binarized image obtained by binarizing the height of each region of the two-dimensional measurement region based on a threshold.

8. The determination method according to claim 6 or 7, wherein the threshold includes a first threshold, and the region is a region having a value higher than the first threshold.

9. The determination method according to any one of claims 6 to 8, wherein the threshold includes a second threshold, and the region is a region having a value lower than the second threshold.

10. The determination method according to claim 9, wherein the second threshold is lower than the first threshold, and the two-dimensional height distribution data consists of a first binarized image obtained by binarizing using the first threshold and a second binarized image obtained by binarizing using the second threshold.

11. The determination method according to any one of claims 1 to 10, wherein the measurement information is three-dimensional position data.

12. The determination method according to claim 11, wherein the three-dimensional position data is point cloud data.

13. The determination method according to any one of claims 1 to 12, wherein determining the surface condition includes determining whether or not there is a predetermined pattern on the surface of the material.

14. The determination method according to claim 13, further comprising notifying whether or not the pattern is present, in accordance with the detection result of the pattern.

15. The determination method according to claim 13 or 14, wherein the determination of the presence or absence of the pattern is performed based on information read from a storage device.

16. The determination method according to any one of claims 13 to 15, further comprising outputting information in order to perform an operation to smooth the surface of the molding material in accordance with the detection result of the pattern.

17. The determination method according to any one of claims 1 to 12, wherein determining the surface condition involves identifying which of the predetermined patterns on the surface of the material the pattern is of.

18. The determination method according to claim 17, further comprising notifying the type of pattern detected.

19. The determination method according to claim 17 or 18, wherein the type of the pattern is determined based on information read from a storage device.

20. The determination method according to any one of claims 17 to 19, wherein the type of pattern is determined based on at least one of the area and aspect ratio of the region.

21. The determination method according to any one of claims 17 to 19, further comprising outputting information in order to selectively perform an operation to smooth the surface of the molding material according to the type of pattern identified.

22. A molding apparatus for molding a three-dimensional object using a molding material, comprising: a supply device capable of supplying powdered molding material; a scanning device capable of scanning an energy beam and melting the molding material supplied by the supply device, the molding apparatus further comprising: a measuring device that acquires measurement information relating to the surface of the molding material supplied by the supply device; and a control device that receives the measurement information measured by the measuring device and outputs the surface state of the surface.

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