Beam scanning device, processing device, and processing method

Abstract

A beam scanning device (7) for scanning a beam which is used in a processing device (2) is provided with: a transmission-type light deflector (73) which a beam from a light source (8) enters and which can change the deflection angle of the beam to be outputted; and a wide-angle unit (74) for expanding the deflection angle of the beam outputted from the light deflector (73).

Description

Beam scanning device, processing device, and processing method

[0001] The present invention relates to a beam scanning device that scans a beam, and a processing device and processing method that process an object using the beam.

[0002] An example of a beam scanning device that scans a beam and a processing device using the beam scanning device is described in Patent Document 1. In such processing devices, there is a demand for miniaturization of the beam scanning device.

[0003] U.S. Publication No. 2021 / 170526

[0004] According to a first aspect, there is provided a beam scanning device for scanning a beam used in a processing device, the beam scanning device comprising: a transmissive optical deflector into which a beam from a light source is incident and which is capable of changing the deflection angle of the emitted beam; and an expanding optical system which expands the deflection angle of the beam emitted from the optical deflector.

[0005] According to a second aspect, there is provided a processing apparatus including the beam scanning apparatus provided by the first aspect, which processes an object using a beam from the beam scanning apparatus.

[0006] According to a third aspect, there is provided a processing apparatus that includes a plurality of beam scanning devices provided by the first aspect and processes an object using beams from the plurality of beam scanning devices, wherein the plurality of beam scanning devices are arranged along a direction intersecting the optical axis.

[0007] According to a fourth aspect, there is provided a processing method including irradiating an object with a beam from the beam scanning device provided by the first aspect, and scanning the beam over the object.

[0008] FIG. 1 is a diagram showing the configuration of a processing system according to this embodiment. FIG. 2 is a diagram showing the configuration of a beam scanning device. FIG. 3 is a diagram showing the configuration of an optical deflector. FIG. 4 is a diagram showing the configuration of an angle widening unit. FIG. 5 is a diagram showing the configuration of a focus unit. FIG. 6 is a diagram explaining how the focus unit moves the focusing position along the beam propagation direction. FIG. 7 is a diagram explaining the role of the focus unit. FIG. 8 is a diagram showing another example of a beam scanning device. FIG. 9 is a diagram showing the configuration of a beam scanning device according to a second embodiment. FIG. 10 is a diagram showing the configuration of a beam scanning device according to a third embodiment. FIG. 11 is a diagram showing the configuration of a beam scanning device according to a fourth embodiment. FIG. 12 is a diagram showing the configuration of a beam scanning device according to a fifth embodiment. FIG. 13 is a diagram showing a modified example of the beam scanning device according to the fifth embodiment. FIG. 14 is a diagram showing another modified example of the beam scanning device according to the fifth embodiment. FIG. 15 is a diagram showing the configuration of a beam scanning device according to a sixth embodiment. FIG. 16 is a diagram showing a modified example of the beam scanning device according to the sixth embodiment. FIG. 17 is a diagram showing the configuration of a beam scanning device according to a seventh embodiment. Fig. 18 is a diagram showing a modified example of the beam scanning device of the seventh embodiment. Fig. 19 is a diagram showing the configuration of the beam scanning device of the eighth embodiment. Fig. 20 is a diagram showing the configuration of an optical deflector used in the beam scanning device of the ninth embodiment. Fig. 21 is a perspective view showing the configuration of a processing device of the tenth embodiment. Fig. 22 is a diagram showing the scanner unit and its periphery as viewed from the y direction. Fig. 23 is a diagram showing how the processing device moves the irradiation range to perform processing. Fig. 24 is a diagram showing the configuration of a processing device of the eleventh embodiment.

[0009] Hereinafter, embodiments of a beam scanning device, a processing device, and a processing method will be described with reference to the drawings. Hereinafter, the embodiments of the beam scanning device, the processing device, and the processing method will be described using a processing system 1 to which the embodiments of the beam scanning device, the processing device, and the processing method are applied. In particular, the following description will be given of an example in which the processing system 1 is a processing system (i.e., an additive processing system) capable of forming a three-dimensional structure (three-dimensional workpiece) by performing additive processing.

[0010] In the following description, the positional relationships of the various components constituting the machining system 1 will be described using an XYZ Cartesian coordinate system defined by mutually orthogonal X, Y, and Z axes. For ease of explanation, the X-axis and Y-axis directions are each assumed to be horizontal (i.e., a predetermined direction within a horizontal plane), and the Z-axis direction is assumed to be vertical (i.e., a direction perpendicular to the horizontal plane, essentially an up-down direction). Furthermore, the rotation directions around the X-axis, Y-axis, and Z-axis (in other words, tilt directions) are referred to as the θX direction, θY direction, and θZ direction, respectively. Here, the Z-axis direction may be the direction of gravity. Furthermore, the XY plane may be assumed to be horizontal.

[0011] (First embodiment) (1) Configuration of machining system 1 First, the configuration of the machining system 1 will be described with reference to Fig. 1. Fig. 1 is a cross-sectional view showing the configuration of the machining system 1.

[0012] As shown in FIG. 1, the processing system 1 includes a processing device 2 and a control unit 3. For ease of explanation, FIG. 1 does not show a cross section of the control unit 3. The processing device 2 is a device capable of forming a three-dimensional structure by performing additive processing. The processing device 2 may also be referred to as an additive processing device. The control unit 3 controls the processing device 2 so as to form a three-dimensional structure by performing additive processing. In other words, the processing device 2 forms a three-dimensional structure under the control of the control unit 3. The processing system 1 including the processing device 2 and the control unit 3 may also be referred to as a processing device.

[0013] In order to form a three-dimensional structure, the processing device 2 includes a material supply tank 4, a recoater 5, a forming tank 6, and two beam scanning devices 7.

[0014] The material supply tank 4 is a container for containing a modeling material M for forming a three-dimensional structure. A bottom surface 41 of the material supply tank 4 is moved in the vertical direction (Z-axis direction) by a drive mechanism (not shown) under the control of the control unit 3. The modeling material M is, for example, a powder. As an example, the modeling material M may be at least one of a metal powder and a resin powder. However, the modeling material M does not have to be a powder.

[0015] The recoater 5, under the control of the control unit 3, supplies the modeling material M contained in the material supply tank 4 to the modeling tank 6. In particular, the recoater 5 flattens the surface of the modeling material M supplied to the modeling tank 6 to form a material layer ML, which is a layer of the modeling material M. The bottom surface of the modeling tank 6 is an elevation stage 61. The elevation stage 61, under the control of the control unit 3, moves in the vertical direction (Z-axis direction) by a drive mechanism (not shown).

[0016] The beam scanning device 7 irradiates at least a portion of the material layer ML formed in the building tank 6 with the processing light EL. Specifically, the beam scanning device 7 irradiates a processing surface MLs, which is at least a portion of the surface of the material layer ML formed in the building tank 6, with the processing light EL. Note that the processing light EL may also be referred to as a processing beam. When the processing light EL is irradiated onto at least a portion of the material layer ML, at least a portion of the material layer ML melts. That is, a molten pool MP is formed in the material layer ML. In other words, a molten pool MP is formed on the processing surface MLs. After that, when the processing light EL is no longer irradiated onto the molten material layer ML (i.e., the molten pool MP), the molten material layer ML solidifies. As a result, a structure layer SL corresponding to the solidified material layer ML is formed. The structure layer SL may be equivalent to a sintered layer formed by sintering the building material M. The structure layer SL may be equivalent to a solidified layer formed by solidifying the molten building material M.

[0017] The beam scanning device 7, under the control of the control unit 3, selectively irradiates the material layer ML with the processing light EL to selectively solidify the material layer ML. To selectively irradiate the material layer ML with the processing light EL, the beam scanning device 7 deflects the processing light EL using an optical deflector (described later). That is, the beam scanning device 7 changes the emission direction of the processing light EL from the beam scanning device 7 using an optical deflector (described later). For example, the beam scanning device 7 deflects the processing light EL along a direction parallel to the lifting stage 61 (i.e., a direction parallel to the material layer ML, which in the example shown in FIG. 1 is a direction parallel to the XY plane). As a result, the irradiation position of the processing light EL on the surface of the material layer ML moves along a direction parallel to the lifting stage 61 (i.e., a direction parallel to the material layer ML and the processing surface MLs, which in the example shown in FIG. 1 is a direction parallel to the XY plane). In this way, the beam scanning device 7 can scan the processing light EL. In other words, the beam scanning device 7 is capable of scanning with the processing light EL. In further other words, the beam scanning device 7 is capable of scanning using the processing light EL. For example, the beam scanning device 7 is capable of scanning at least a portion of the material layer ML with the processing light EL. For example, the beam scanning device 7 is capable of scanning the processing surface MLs with the processing light EL.

[0018] After the structure layer SL is formed, the lift stage 61 descends. After the lift stage 61 descends (in the example shown in FIG. 1 , the lift stage 61 moves toward the −Z side), the recoater 5 forms a new material layer ML on the lift stage 61 (more specifically, on the already-formed structure layer SL and the already-formed old material layer ML). Then, the beam scanning device 7 irradiates the newly formed material layer ML with the processing light EL. That is, the beam scanning device 7 irradiates the processing surface MLs, which is at least a part of the surface of the newly formed material layer ML, with the processing light EL. In other words, the beam scanning device 7 irradiates the uppermost material layer ML with the processing light EL. That is, the beam scanning device 7 irradiates the processing surface MLs, which is at least a part of the surface of the uppermost material layer ML, with the processing light EL. As a result, a new structure layer SL is formed on the already-formed structure layer SL. That is, the new structure layer SL is stacked on the already-formed structure layer SL.

[0019] Thereafter, the processing apparatus 2 repeats the same operations under the control of the control unit 3. That is, the processing apparatus 2 alternately repeats an operation of forming a material layer ML mainly using the recoater 5, an operation of solidifying at least a portion of the material layer ML to form a structure layer SL mainly using the beam scanning device 7, and an operation of lowering the lifting stage 61. As a result, a three-dimensional structure in which a plurality of structure layers SL are stacked is formed on the lifting stage 61. That is, the processing apparatus 2 performs additional processing on the lifting stage 61 (specifically, performs additional processing using the material layer ML formed on the lifting stage 61), thereby forming a three-dimensional structure on the lifting stage 61. In other words, the processing apparatus 2 performs additional processing on the lifting stage 61 using the material layer ML formed on the lifting stage 61, thereby forming a three-dimensional structure on the lifting stage 61. In this way, the processing device 2 performs additive processing based on powder bed fusion (PBF) such as selective laser sintering (SLS) to form a three-dimensional structure.

[0020] The control unit 3 is capable of controlling the operation of the processing device 2. For example, the control unit 3 may be capable of controlling the movement of the lift stage 61. That is, the control unit 3 may be capable of controlling the lift stage 61. For example, the control unit 3 may be capable of controlling the formation of the material layer ML by the recoater 5. That is, the control unit 3 may be capable of controlling the recoater 5. For example, the control unit 3 may be capable of controlling the irradiation of the processing light EL by the beam scanning device 7. That is, the control unit 3 may be capable of controlling the beam scanning device 7.

[0021] The control unit 3 may include, for example, an arithmetic device 31 and a storage device 32. The arithmetic device 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, a memory. The control unit 3 functions as a device that controls the operation of the machining device 2 when the arithmetic device 31 executes a computer program. This computer program is a computer program for causing the arithmetic device 31 to perform (i.e., execute) the operations to be performed by the control unit 3, which will be described later. In other words, this computer program is a computer program for causing the control unit 3 to function so as to cause the machining device 2 to perform the operations to be performed by the control unit 3. The computer program executed by the arithmetic device 31 may be recorded in the storage device 32 (i.e., a recording medium) included in the control unit 3, or may be recorded in any storage medium (e.g., a hard disk or a semiconductor memory) built into the control unit 3 or externally attachable to the control unit 3. Alternatively, the arithmetic device 31 may download the computer program to be executed via a network interface from a device external to the control unit 3. The storage device 32 may also be called a recording device.

[0022] The control unit 3 may be provided as a server or the like outside the machining system 1. In this case, the control unit 3 and the machining system 1 may be connected via a wired and / or wireless network (or a data bus and / or a communication line). As the wired network, for example, a network using a serial bus interface represented by at least one of IEEE1394, RS-232x, RS-422, RS-423, RS-485, and USB may be used. As the wired network, a network using a parallel bus interface may be used. As the wired network, a network using an interface compliant with Ethernet (registered trademark) represented by at least one of 10BASE-T, 100BASE-TX, and 1000BASE-T may be used. As the wireless network, a network using radio waves may be used. An example of a network using radio waves is a network conforming to IEEE802.1x (for example, at least one of a wireless LAN and Bluetooth (registered trademark)). A network using infrared rays may be used as a wireless network. A network using optical communication may be used as a wireless network. In this case, the control unit 3 and the processing system 1 may be configured to be able to send and receive various information via the network.

[0023] Furthermore, the control unit 3 may be capable of transmitting information such as commands and control parameters to the machining system 1 via a network. The machining system 1 may include a receiving device that receives information such as commands and control parameters from the control unit 3 via the network. The machining system 1 may include a transmitting device that transmits information such as commands and control parameters to the control unit 3 via the network (i.e., an output device that outputs information to the control unit 3). Note that an apparatus including the machining system 1 and the control unit 3 may be referred to as a machining system.

[0024] Alternatively, the control unit 3 may be provided inside the processing system 1. That is, the processing system 1 may include the control unit 3. Alternatively, a first control device that performs part of the processing performed by the control unit 3 may be provided inside the processing system 1, while a second control device that performs another part of the processing performed by the control unit 3 may be provided outside the processing system 1.

[0025] A computational model that can be constructed by machine learning may be implemented in the control unit 3 by the computation device 31 executing a computer program. An example of a computational model that can be constructed by machine learning is a computational model including a neural network (so-called artificial intelligence (AI)). In this case, learning of the computational model may include learning of parameters of the neural network (e.g., at least one of a weight and a bias). The control unit 3 may control the operation of the processing device 2 using the computational model. That is, the operation of controlling the operation of the processing device 2 may include the operation of controlling the operation of the processing device 2 using the computational model. Note that a computational model that has been constructed by offline machine learning using teacher data may be implemented in the control unit 3. Furthermore, the computational model implemented in the control unit 3 may be updated by online machine learning on the control unit 3. Alternatively, the control unit 3 may control the operation of the processing device 2 using a computational model implemented in a device external to the control unit 3 (i.e., a device provided outside the processing system 1) in addition to or instead of the computational model implemented in the control unit 3.

[0026] The recording medium for recording the computer program executed by the control unit 3 may be at least one of the following: a CD-ROM, CD-R, CD-RW, a flexible disk, an MO, a DVD-ROM, a DVD-RAM, a DVD-R, a DVD+R, a DVD-RW, a DVD+RW, or an optical disk such as Blu-ray (registered trademark), a magnetic medium such as a magnetic tape, a magneto-optical disk, a semiconductor memory such as a USB memory, or any other medium capable of storing a program. The recording medium may also include a device capable of recording a computer program (for example, a general-purpose device or a dedicated device in which a computer program is implemented in an executable state in at least one form such as software or firmware). Furthermore, each process or function included in the computer program may be realized by a logical processing block realized within the control unit 3 when the control unit 3 (i.e., the computer) executes the computer program, or may be realized by a predetermined gate array (for example, hardware such as an FPGA (Field Programmable Gate Array) or an ASIC (Application Specific Integrated Circuit)) provided in the control unit 3, or may be realized in a form that combines logical processing blocks and partial hardware modules that realize some elements of the hardware.

[0027] (2) Configuration of Beam Scanning Device 7 Next, the configuration of the beam scanning device 7 will be described with reference to Fig. 2. Fig. 2 is a diagram showing the configuration of the beam scanning device 7. Note that the configuration of the beam scanning device 7 shown in Fig. 2 is an example, and the configuration of the beam scanning device 7 is not limited to the configuration shown in Fig. 2.

[0028] As shown in FIG. 2, the beam scanning device 7 includes a focus unit 71 , a condenser lens 72 , an optical deflector 73 , and an angle widening unit 74 .

[0029] The processing light EL emitted by the beam scanning device 7 toward the material layer ML is supplied to the beam scanning device 7 from a light source 8 included in the processing system 1 (or a light source 8 external to the processing system 1). The light source 8 generates the processing light EL. In this embodiment, an example will be described in which the light source 8 generates infrared light as the processing light EL. That is, the light source 8 generates processing light EL having a peak wavelength of 1000 nm or a wavelength around 1000 nm. In other words, the light source 8 generates processing light EL in a wavelength band having a peak wavelength of 1000 nm or a wavelength around 1000 nm. However, the light source 8 may generate light other than infrared light as the processing light EL. For example, the light source 8 may generate at least one of visible light and ultraviolet light as the processing light EL. In this embodiment, a photonic crystal laser is used as an example of the light source 8.

[0030] In the present embodiment, a light source capable of changing the cross-sectional intensity profile of the emitted processing light EL may be used as the light source 8. Examples of light sources capable of changing the cross-sectional intensity profile of the emitted processing light EL are described in, for example, U.S. Patent No. 10,423,015 and International Patent Publication No. 2023 / 056435.

[0031] The processed light EL generated by the light source 8 is supplied from the light source 8 to the beam scanning device 7. The method for supplying the processed light EL generated by the light source 8 to the beam scanning device 7 is arbitrary, and for example, the processed light EL may be supplied via an optical fiber, or may be supplied from the light source 8 to the beam scanning device 7 via a mirror.

[0032] Next, each component of the beam scanning device 7 will be described. The optical deflector 73 is a transmissive optical deflector 73. A beam from a light source enters the optical deflector 73 through an incident surface 733, and the light that has entered the optical deflector 73 exits from an exit surface 734. In other words, a beam enters the optical deflector 73 through the incident surface 733 located on one side in the direction of an axis passing through the optical deflector 73, and exits from the exit surface 734 located on the other side in the direction of this axis. The optical deflector 73 can change the deflection angle of the exiting beam with respect to the optical axis of the incident beam.

[0033] FIG. 3 shows the configuration of the optical deflector 73. The optical deflector 73 has a roughly rectangular parallelepiped KTN (potassium tantalate niobate) crystal 731, with metal electrode films 732 attached to two opposing surfaces across the optical axis. Applying a signal voltage to the two metal electrode films 732 changes the refractive index of the KTN crystal 731, causing the light emitted from the KTN crystal 731 to be deflected about an axis along the propagation direction of the incident light. The deflection angle of the beam emitted from the KTN crystal 731 (the axis along the propagation direction of the beam incident on the KTN crystal 731, or the angle of the axis along the propagation direction of the emitted beam relative to the optical axis of the beam scanning device 7—particularly, the optical axis of the beam scanning device 7 on the light source side of the KTN crystal 731) changes depending on the level of the signal voltage applied to the KTN crystal 731.

[0034] FIG. 4 is a diagram showing the configuration of the wide-angle unit 74. The wide-angle unit 74 includes, from the side closest to the printing surface, a lens group G1 with positive power, a lens group G2 with negative power, and a lens group G3 with positive power. In other words, the wide-angle unit 74 includes, from the side closest to the printing surface, a lens group G1 with a positive focal length, a lens group G2 with a negative focal length, and a lens group G3 with a positive focal length. For example, the focal length of the lens group G1 may be +100 mm, the focal length of the lens group G2 may be −8 mm, and the focal length of the lens group G3 may be +40 mm. The wide-angle unit 74 as a whole has positive power. In other words, the focal length of the entire wide-angle unit 74 is positive, and a focused spot can be created on the printing surface. The wide-angle unit 74 may also be referred to as a magnifying optical system. The entrance pupil position of the angle widening unit 74 is positioned inside the optical deflector 73 or in the vicinity of the optical deflector 73 .

[0035] Each of the lens groups G1 to G3 may be composed of multiple lenses or a single lens. The boundary between the lens groups may be located at a position where the lens spacing is greater than the maximum lens spacing among the lenses constituting the corresponding lens group. The position of the incident beam incident on the lens surface located nearest to the entrance side among the one or more lenses constituting the lens group is defined as the incident position of the incident beam on that lens group.

[0036] The relationship between the chief ray angle of the off-axis light beam incident on the angle widening unit 74 and the chief ray angle of the off-axis light beam emerging from the angle widening unit 74 may be such that the chief ray angle of the incident off-axis light beam is smaller than the chief ray angle of the emerging off-axis light beam. In this case, the angle widening unit 74 can increase the beam deflection angle of the optical deflector 73.

[0037] To achieve a chief ray angle of the incident off-axial light beam less than that of the exiting off-axial light beam, the angle-widening unit 74 may satisfy the following three conditions: (i) the chief ray CR of the off-axial light beam R2 incident on the lens group G2 moves away from the optical axis Ax. This is because if the off-axial light beam R2 passes along the optical axis Ax, the chief ray CR is not refracted by the lens group G2, and therefore the deflection angle cannot be increased. (ii) the divergence angles of the on-axial light beam and the off-axial light beam are reduced by the lens group G3 so that the divergence angle of the light beam by the lens group G2 does not become too wide. This condition causes the light beam (on-axial light beam and off-axial light beam) to converge by the lens group G3, thereby assisting the light beam convergence effect by the lens group G1. (iii) Chief ray height in lens group G2<Chief ray height in lens group G1 When this condition is satisfied, the deflection angle of the obliquely incident light beam can be increased by the negatively powered lens group G2, thereby expanding the deflection angle of the beam.

[0038] Furthermore, the angle-widening unit 74 may satisfy the following two conditions in order for the on-axis light beam and the off-axis light beam to form a focused spot on the printing surface: (iv) The lens group G1 is used to converge the light beam incident on the lens group G2. Because the lens group G2 has negative power, the light beam diverges. That is, the divergence angle of the light beam emerging from the lens group G2 is larger than the divergence angle of the light beam incident on the lens group G2. When the light beam incident on the lens group G2 is convergent, the convergence angle of the light beam emerging from the lens group G2 is smaller than the convergence angle of the incident light beam, or the light beam is in a divergent state. The lens group G1 reduces the divergence angle of the light beam diverged by the lens group G2 to form a focused spot on or near the printing surface. (v) To prevent the angle of the chief ray of the off-axis light beam from being reduced too much by the lens group G3, the chief ray of the off-axis light beam incident on the lens group G3 is brought close to the optical axis. Specifically, the distance between the optical deflector 73 and the lens group G3 is made narrower than the distance between the lens group G3 and the lens group G2.

[0039] The position of incidence of the off-axis light beam incident on the lens group G3 is moved closer to the optical axis Ax so that the chief ray angle of the off-axis light beam is not reduced too much by the lens group G3, because if the chief ray angle of the off-axis light beam is reduced, the deflection angle cannot be increased too much.

[0040] FIG. 5 is a diagram showing the configuration of the focusing unit 71. The focusing unit 71 has a function of moving the focusing position along the beam propagation direction. As shown in FIG. 5, the focusing unit 71 has a substantially rectangular parallelepiped KTN crystal 711. Two metal electrode films 712a and 712b (hereinafter, both of which are collectively referred to as "metal electrode films 712") are attached to the light incident surface of the KTN crystal 711, and two metal electrode films 713a and 713b (hereinafter, both of which are collectively referred to as "metal electrode films 713") are attached to the light exit surface.

[0041] A beam from the light source is incident on the region between the metal electrode film 712a and the metal electrode film 712b and is emitted from the region between the metal electrode film 713a and the metal electrode film 713b. In other words, the metal electrode film 712a and the metal electrode film 712b are formed so as to sandwich the optical axis of the light passing through the KTN crystal 711, and the metal electrode film 713a and the metal electrode film 713b are formed so as to sandwich the optical axis of the light passing through the KTN crystal 711.

[0042] 6 is a diagram illustrating how the focusing unit 71 moves the focusing position along the beam propagation direction. As shown in FIG. 6, a positive voltage is applied to the metal electrode films 712a and 712b on the incident surface, and a negative voltage is applied to the metal electrode films 713a and 713b on the exit side. The dashed-dotted lines EF inside the KTN crystal 711 indicate the electric field lines generated when a voltage is applied to the metal electrode films 712 and 713.

[0043] 6, an electric field is generated between the metal electrode films 712a and 713a, and between the metal electrode films 712b and 713b. An electric field is also generated between the metal electrode films 712a and 712b, and between the metal electrode films 713a and 713b. In other words, an electric field is also generated in the optical path of the beam passing through the KTN crystal 711. This electric field is stronger near the metal electrode films 712 and 713, and becomes weaker toward the center.

[0044] The electro-optic effect (EO effect) of the KTN crystal 711 causes a change in refractive power in proportion to the square of the electric field, so the refractive power changes significantly in areas close to the metal electrode films 712 and 713, and the change in refractive power is small in the central area. Since light tends to travel in the direction of higher refractive power, when light R3 enters the KTN crystal 711, light R4 is emitted that is focused in the central area. The higher the voltage applied, the greater the change in refractive power, so the beam is more strongly focused, and the focus moves closer to the KTN crystal 711. Using the above mechanism, the focusing position can be moved using the KTN crystal 711.

[0045] Fig. 7 is a diagram for explaining the role of the focus unit 71. Fig. 7 is a diagram showing events that may occur when the focus unit 71 is not present. The events described here do not necessarily occur, but may occur depending on the balance of other components.

[0046] The configuration in which the deflection angle of the optical deflector 73 is further widened by the angle widening unit 74 may cause a misalignment between the on-axis spot position (i.e., the on-axis focal position) and the off-axis spot position (i.e., the off-axis focal position). If the on-axis spot position is aligned with the printing surface, the off-axis spot position may be located, for example, in front of the printing surface (point F in Figure 7), and a situation may occur in which the desired spot is not formed on the printing surface.

[0047] The focus unit 71 has a role of moving the light condensing position so that an appropriate spot is formed on the modeling surface. Note that the control unit 3 may control the focus unit 71 based on the deflection angle of the optical deflector 73. This is because the larger the deflection angle, the farther the light condensing position tends to be from the modeling surface.

[0048] As an example, a table of the correspondence between deflection angles and focal positions is stored in advance in the storage device 32. The control unit 3 transmits a control signal corresponding to the swing angle to the optical deflector 73, reads data on the focal position corresponding to that swing angle from the table, and transmits a control signal to the focus unit 71 so that the focal position is located on the printing surface. That is, the control unit 3 controls the focus unit 71 to move the focal point of the beam according to the angle at which the optical deflector 73 deflects the beam. The correspondence between the deflection angle and the focal position may be calculated from design data of the angle widening unit 74 or may be generated based on actual measurement data. In this way, when the surface on which the beam is to be focused to form a spot is, for example, a flat surface, the focus unit 71 can continue to adjust the focal position to this plane even when the optical deflector 73 scans the beam within the plane.

[0049] Returning to Fig. 2, the condenser lens 72 has the role of suppressing the effect of the widening of the spot diameter caused by the angle widening unit 74 having a magnification. The condenser lens 72 may be used to adjust the diameter of the beam incident on the optical deflector 73. Note that the condenser lens 72 is not essential, and the beam scanning device 7 may be configured without using the condenser lens 72 as shown in Fig. 8.

[0050] The above describes the beam scanning device 7 according to the first embodiment, and the processing device 2 and processing system 1 using the beam scanning device 7. The beam scanning device 7 according to the first embodiment includes an optical deflector 73 that receives a beam from a light source and can change the deflection angle of the emitted beam. The optical deflector 73 changes the deflection angle by applying a voltage to a KTN crystal 731, allowing the beam deflection angle to be changed with a more compact configuration than, for example, a configuration using a galvanometer scanner. Furthermore, the beam scanning device 7 includes an angle widening unit 74 consisting of a magnifying optical system downstream of the optical deflector 73, which can be used in the processing device 2 by widening the deflection angle of the optical deflector 73. In other words, the angle widening unit 74 widens the deflection angle of the optical deflector 73, enabling scanning over a practically required angular range. Furthermore, the beam scanning device 7 according to the first embodiment can make the optical path of the beam within the beam scanning device 7 nearly linear, thereby enabling the size of the beam scanning device 7 in the direction perpendicular to the optical axis to be reduced.

[0051] Furthermore, the beam scanning device 7 of the first embodiment uses the KTN crystal 711 to form the focus unit 71, and therefore has a compact configuration and is capable of moving the focus faster than a focus device that uses lens driving.

[0052] Second Embodiment Fig. 9 is a diagram showing the configuration of a beam scanning device 7 according to a second embodiment. The beam scanning device 7 according to the second embodiment is used, for example, as the beam scanning device 7 of the processing system shown in Fig. 1. The processing light EL generated by the light source 8 is supplied from the light source 8 to the beam scanning device 7. The method for supplying the processing light EL generated by the light source 8 to the beam scanning device 7 is arbitrary. For example, the processing light EL may be supplied via an optical fiber, or may be supplied from the light source 8 to the beam scanning device 7 via a mirror.

[0053] The beam scanning device 7 of the second embodiment includes a focus unit 71, a zoom lens 75, an optical deflector 73, and an angle widening unit 74. The beam scanning device 7 of the second embodiment uses a zoom lens 75 instead of the condenser lens 72 of the first embodiment. The configurations of the focus unit 71, the optical deflector 73, and the angle widening unit 74 in the second embodiment are the same as the configurations of the focus unit 71, the optical deflector 73, and the angle widening unit 74 described in the first embodiment, and therefore will not be described here.

[0054] A zoom lens 75 is disposed in the optical path between the focus unit 71 and the optical deflector 73 in the beam scanning device 7 according to the second embodiment.

[0055] The zoom lens 75 includes a lens 751 with positive power and a lens 752 with negative power, arranged from the side closest to the printing surface. The magnification of the zoom lens 75 is changed by moving at least one of the lens 751 with positive power and the lens 752 with negative power. The response speed of the zoom lens 75 can be slower than the movement of the focal position by the focus unit 71 or the beam scanning by the optical deflector 73, so it can be realized with a lens-moving configuration. Note that the zoom lens 75 shown in FIG. 9 is an example and is not limited thereto. For example, the zoom lens may be a combination of a lens with negative power and a lens with positive power, arranged from the side closest to the printing surface, or a combination of a lens with positive power, a lens with negative power, and a lens with positive power, arranged from the side closest to the printing surface. A varifocal lens, whose focal length changes with a change in magnification, can also be applied, and the change in focal length when the magnification is changed may be corrected using the focus unit 71. Here, the zoom lens 75 and the varifocal lens may be referred to as a variable magnification optical system.

[0056] 10 is a diagram showing the configuration of a beam scanning device 7 according to a third embodiment. The beam scanning device 7 according to the third embodiment is used as the beam scanning device 7 of the processing system shown in FIG. 1, for example. The processing light EL generated by the light source 8 is supplied from the light source 8 to the beam scanning device 7.

[0057] The beam scanning device 7 of the third embodiment includes a focus unit 71, a condenser lens 72, an optical deflector 73, and an angle widening unit 74. The configurations of the focus unit 71, the condenser lens 72, the optical deflector 73, and the angle widening unit 74 in the third embodiment are the same as the configurations of the focus unit 71, the condenser lens 72, the optical deflector 73, and the angle widening unit 74 described in the first embodiment, and therefore a description thereof will be omitted here.

[0058] The beam scanning device 7 of the third embodiment includes a dichroic mirror 76 disposed in the optical path between the light source 8 and the focusing unit 71. The dichroic mirror 76 reflects light of a specific wavelength band and transmits light of other wavelength bands. In this embodiment, the dichroic mirror 76 reflects the processing light EL emitted from the light source 8 and guides it to the focusing unit 71. The dichroic mirror 76 also transmits light reflected from the build surface and light generated from the build surface, such as light from the molten pool MP. The light from the build surface passes through the angle widening unit 74, the optical deflector 73, the condenser lens 72, and the focusing unit 71 to reach the dichroic mirror 76, where it is transmitted through the dichroic mirror 76 and input to the monitor 9.

[0059] When the beam scanning device 7 irradiates the material layer ML on the build surface with processing light EL, a portion of the material layer ML melts to form a molten pool MP, which then solidifies to form a structure layer SL. The monitor 9 captures the light from the build surface, allowing the molten pool MP and structure layer SL to be observed. In other words, the powder bed and the built object can be observed on the monitor 9.

[0060] Although the third embodiment has been described as including a dichroic mirror 76 that reflects the processing light EL and transmits the observation light, it is also possible to use a dichroic mirror that transmits the processing light EL and reflects the observation light. In this case, the positional relationship between the light source 8 and the monitor 9 is reversed.

[0061] 11 is a diagram showing the configuration of a beam scanning device 7 according to a fourth embodiment. The beam scanning device 7 according to the fourth embodiment is used, for example, as the beam scanning device 7 of the processing system shown in FIG. Processing light EL generated by a light source (not shown) is supplied to the beam scanning device 7 via an optical fiber 81.

[0062] The beam scanning device 7 of the fourth embodiment includes a focus unit 71, a condenser lens 72, an optical deflector 73, and an angle widening unit 74. The configurations of the focus unit 71, the condenser lens 72, the optical deflector 73, and the angle widening unit 74 in the fourth embodiment are the same as the configurations of the focus unit 71, the condenser lens 72, the optical deflector 73, and the angle widening unit 74 described in the first embodiment, and therefore a description thereof will be omitted here.

[0063] The beam scanning device 7 of the fourth embodiment includes an input lens 77 arranged in the optical path between the light source 8 and the focus unit 71. The input lens 77 is a positive lens that serves to collimate the divergent light emitted from the optical fiber 81. The light that has passed through the input lens 77 and is approximately collimated is input to the focus unit 71.

[0064] According to the configuration of the beam scanning device 7 of the fourth embodiment, instead of incorporating a light source inside the beam scanning device 7, the processing light EL can be transmitted by the optical fiber 81. The optical fiber 81 may also be referred to as a light guide.

[0065] 12 is a diagram showing the configuration of a beam scanning device 7 according to a fifth embodiment. The beam scanning device 7 according to the fifth embodiment is used, for example, as the beam scanning device 7 of the processing system shown in FIG. Processing light EL generated by a light source (not shown) is supplied to the beam scanning device 7 via an optical fiber 81.

[0066] The beam scanning device 7 of the fifth embodiment includes a focus unit 71, a condenser lens 72, an optical deflector 73, and an angle widening unit 74. The configurations of the focus unit 71, the condenser lens 72, the optical deflector 73, and the angle widening unit 74 in the fifth embodiment are the same as the configurations of the focus unit 71, the condenser lens 72, the optical deflector 73, and the angle widening unit 74 described in the first embodiment, and therefore a description thereof will be omitted here.

[0067] Similarly to the fourth embodiment, the beam scanning device 7 of the fifth embodiment includes an input lens 77 arranged in the optical path between the optical fiber 81 and the focus unit 71. The input lens 77 is a positive lens that serves to collimate the divergent light emitted from the optical fiber 81. The light that has passed through the input lens 77 and is approximately collimated is input to the dichroic mirror 76.

[0068] In this embodiment, the dichroic mirror 76 transmits the processing light EL emitted from the light source 8 and guides it to the focusing unit 71, while also reflecting light reflected from the build surface and light generated from the build surface, such as light from the molten pool MP. The light from the build surface passes through the angle widening unit 74, the optical deflector 73, the condenser lens 72, and the focusing unit 71 to reach the dichroic mirror 76 and is reflected by the dichroic mirror 76. The light reflected by the dichroic mirror 76 is reflected again by the mirror 78 and then input to the monitor 9. Because the mirror 78 deflects the light traveling from the dichroic mirror 76 in the lateral direction (the direction intersecting the optical axis of the beam scanning device 7) toward approximately the optical axis direction, the monitor 9 can be mounted above the beam scanning device 7. This eliminates the need to install the monitor 9 laterally of the beam scanning device 7, allowing for closer spacing when multiple beam scanning devices are integrated.

[0069] When the beam scanning device 7 irradiates the material layer ML on the build surface with processing light EL, a portion of the material layer ML melts to form a molten pool MP, which then solidifies to form a structure layer SL. The monitor 9 captures the light from the build surface, allowing the molten pool MP and structure layer SL to be observed. In other words, the powder bed and the built object can be observed on the monitor 9.

[0070] Although the fifth embodiment has been described as including a dichroic mirror 76 that transmits the processing light EL and reflects the observation light, it is also possible to use a dichroic mirror that reflects the processing light EL and transmits the observation light. In this case, the positional relationship between the optical fiber 81 and the monitor 9 is reversed.

[0071] Fig. 13 is a diagram showing a modification of the beam scanning device 7 of the fifth embodiment. In the beam scanning device 7 shown in Fig. 12, the dichroic mirror 76 and the mirror 78 are arranged at an angle of 45 degrees with respect to the optical path and reflect the observation light at a right angle, but in the beam scanning device 7 according to the modification, the dichroic mirror 76 and the mirror 78 are arranged so that the normal to their reflecting surfaces forms an angle of less than 45 degrees with respect to the optical path.

[0072] Fig. 14 is a diagram showing another modified example of the beam scanning device of the fifth embodiment. The beam scanning device 7 shown in Fig. 14 has a control unit 3 in the empty space next to the focus unit 71, condenser lens 72, optical deflector 73, and angle widening unit 74 in the configuration of the beam scanning device 7 shown in Fig. 13. The beam scanning device 7 and the control unit 3 may be housed in the same housing, or the control unit 3 may be located outside the housing of the beam scanning device 7. Note that when multiple beam scanning devices 7 are provided, multiple beam scanning devices 7 may be controlled by one control unit 3.

[0073] 15 is a diagram showing the configuration of a beam scanning device 7 according to a sixth embodiment. In the sixth embodiment, the beam scanning device 7 includes a plurality of beam scanning units 70 arranged in one direction. The beam scanning unit 70 according to the sixth embodiment is used as the beam scanning device 7 of the processing system 1 in FIG. 1, for example. Processing light EL generated by a light source (not shown) is supplied to the beam scanning device 7 via an optical fiber 81.

[0074] Each beam scanning unit 70 includes a focusing unit 71, a condensing lens 72, an optical deflector 73, an angle widening unit 74, and a housing that houses these. The housing is a substantially rectangular parallelepiped, and the dimension along the direction intersecting the optical axis of the magnifying optical system is smaller than the dimension along the optical axis. The configurations of the focusing unit 71, condensing lens 72, optical deflector 73, and angle widening unit 74 housed in the housing are the same as the configurations of the focusing unit 71, condensing lens 72, optical deflector 73, and angle widening unit 74 described in the first embodiment, so a description thereof will be omitted here.

[0075] The beam scanning device 7 includes an input lens 77 having a positive lens that serves to collimate the divergent light emitted from the optical fiber 81. The beam that has passed through the input lens 77 and is approximately collimated travels along the arrangement direction of the plurality of beam scanning units 70 and is guided to each beam scanning unit 70. Each beam scanning unit 70 has beam splitters 791 to 795, and the beam that has been approximately collimated by the input lens 77 is reflected by the beam splitters 791 to 795 and is incident on the focus lens 71 of each beam scanning device 7.

[0076] Of the processing light EL output from optical fiber 81 and approximately collimated, 20% of the incident light is reflected by beam splitter 791, with 80% transmitting. Of the processing light EL that passes through beam splitter 791, 25% is reflected by beam splitter 792, with 75% transmitting. Of the processing light EL that passes through beam splitter 792, 33.3% is reflected by beam splitter 793, with 66.7% transmitting. Of the processing light EL that passes through beam splitter 793, 50% is reflected by beam splitter 794, with 50% transmitting. Of the processing light EL that passes through beam splitter 794, 100% is reflected by beam splitter 795. With this configuration, 20% of the processing light EL output from the optical fiber 81 is reflected by each of the beam splitters 791 to 795 and supplied to each of the beam scanning device units 70 .

[0077] Here, it can be said that beam splitter 791 has a light intensity division ratio of 80:20 in the wavelength band of the processed light EL, beam splitter 792 has a light intensity division ratio of 75:25 in the wavelength band of the processed light EL, beam splitter 793 has a light intensity division ratio of 66.7:33.3 in the wavelength band of the processed light EL, and beam splitter 794 has a light intensity division ratio of 50:50 in the wavelength band of the processed light EL.

[0078] Each beam scanning unit 70 is equipped with a monitor 9 that receives the observation light reflected from the modeling surface. Therefore, each beam splitter 791-795 has the light intensity division ratio described above in the wavelength band of the processing light EL, but may transmit almost 100% of the light intensity in the wavelength band of the observation light. Therefore, the beam splitter 795 may be referred to as a dichroic mirror. Note that, although all beam scanning units 70 are equipped with monitors 9 in the example shown in FIG. 15 , some beam scanning units 70 may not be equipped with monitors 9.

[0079] Fig. 16 is a diagram showing a modified example of the beam scanning device 7 of the sixth embodiment. The beam scanning device 7 shown in Fig. 16 has a plurality of beam scanning units 70 arranged in a matrix. In other words, the beam scanning device 7 of Fig. 16 includes a plurality of beam scanning units 70 arranged two-dimensionally in a plane intersecting the optical axis of each beam scanning unit 70. Note that the arrangement of the plurality of beam scanning units 70 is not limited to a matrix arrangement, and may be, for example, a staggered arrangement or a random arrangement.

[0080] In Fig. 16, the five beam scanning units 70 indicated by the symbol S correspond to the beam scanning units 70 described in Fig. 15. That is, the beam scanning device 7 according to the modified example has a configuration in which the plurality of beam scanning units 70 described in Fig. 15 are arranged in multiple stages. The processing light EL is distributed and supplied to each beam scanning unit 70 by a semi-transparent mirror 79. As with the semi-transparent mirrors 791 to 795 described in Fig. 15, it is preferable that the distribution of the processing light EL by the beam splitter 79 be such that the amount of light reflected by each beam splitter 79 is the same.

[0081] By arranging multiple beam scanning units 70 two-dimensionally in this manner, the beam irradiation amount per unit footprint of the beam scanning device 7 can be increased. Furthermore, the positions from which multiple processing beams are emitted can be brought closer together. For example, mechanical steering scanners such as galvanometer scanners have a physical drive mechanism, so they cannot be arranged in an integrated manner as shown in FIGS. 15 and 16 . By using the beam scanning device 7 of the sixth embodiment in the processing device 2, an improvement in processing throughput can be expected.

[0082] Seventh Embodiment FIG. 17 is a diagram showing the configuration of a beam scanning device 7 according to a seventh embodiment. The beam scanning device 7 includes a plurality of beam scanning units 70. Each beam scanning unit 70 includes a focus unit 71, a condenser lens 72, an optical deflector 73, and an angle widening unit 74. The plurality of beam scanning units 70 are arranged on a circle approximately centered on the surface to be formed, with the beam irradiation direction facing the surface to be formed. The irradiation ranges on the surface to be formed of each beam scanning unit 70 are the same, as shown in FIG. 17. This allows beams from the plurality of beam scanning units 70 to be irradiated onto a predetermined irradiation range, enabling efficient processing.

[0083] Although Figure 17 shows an example in which the irradiation ranges of each beam scanning unit 70 are the same, the irradiation ranges of each beam scanning unit 70 may be slightly misaligned as long as they at least partially overlap each other.

[0084] Fig. 18 is a diagram showing a modified example of the beam scanning device 7 of the seventh embodiment. The beam scanning device 7 shown in Fig. 18 has a plurality of beam scanning units 70. As shown in Fig. 18, the plurality of beam scanning units 70 may be arranged three-dimensionally facing the modeling surface.

[0085] Eighth Embodiment Fig. 19 is a diagram showing the configuration of a beam scanning device 7 according to an eighth embodiment. In the eighth embodiment, the beam scanning device 7 includes a plurality of beam scanning units 70a to 70e arranged along at least one direction. The beam scanning device 7 according to the eighth embodiment is used, for example, as the beam scanning device 7 of the processing system 1 shown in Fig. 1. Processing light EL output from a light source 8 is supplied to the beam scanning device 7.

[0086] Each of the beam scanning units 70a to 70e includes a focus unit 71a to 71e, a condenser lens 72a to 72e, an optical deflector 73a to 73e, and an angle widening unit 74a to 74e. The configurations of the focus units 71a to 71e, the condenser lens 72a to 72e, the optical deflector 73a to 73e, and the angle widening unit 74a to 74e in the eighth embodiment are the same as the configurations of the focus unit 71, the condenser lens 72, the optical deflector 73, and the angle widening unit 74 described in the first embodiment, and therefore will not be described here.

[0087] In the eighth embodiment, the configurations of the multiple beam scanning units 70a-70e are slightly different from each other. Specifically, the beam scanning units 70a-70e are arranged such that the angle widening units 74a-74e are shifted by different amounts relative to the axis of the processing light EL input to the beam scanning units 70a-70e. Here, the optical axis of the angle widening unit 74c is an axis passing through the center of curvature of the lens surfaces of the lenses G1-G3 that make up the angle widening unit 74c. Note that the axis of the processing light EL may be an axis along a straight line connecting the center of gravity of the intensity distribution of the processing light EL on a first surface perpendicular to the traveling direction of the processing light EL and the center of gravity of the intensity distribution of the processing light EL on a second surface perpendicular to the traveling direction of the processing light EL at a location different from the first surface in the traveling direction of the processing light EL. The shift amount of each of the angle widening units 74a to 74e may be determined based on the optical axis of the optical system on the light source side of each of the angle widening units 74a to 74e in each of the beam scanning units 70a to 70e.

[0088] In the central beam scanning unit 70c, the axis of the processing light EL and the optical axis of the angle widening unit 74c are aligned, and the shift amount is 0. In the left-side beam scanning units 70a and 70b, the optical axes of the angle widening units 74a and 74b are shifted to the right relative to the axis of the processing light EL. The shift amount of the leftmost beam scanning unit 70a is larger than the shift amount of the second-from-the-left beam scanning unit 70b. In the right-side beam scanning units 70d and 70e, opposite to the left-side beam scanning units 70a and 70b, the optical axes of the angle widening units 74d and 74e are shifted to the left relative to the axis of the processing light EL. The shift amount of the rightmost beam scanning unit 70e is larger than the shift amount of the second-from-the-right beam scanning unit 70d.

[0089] Because the optical axes of the angle-widening units 74a, 74b, 74d, and 74e are shifted from the axis of the processing light EL, the deflection angles of the angle-widening units 74a, 74b, 74d, and 74e are larger on the shifted side, and the processing light EL is directed in the shifted direction. In the left-side beam scanning units 70a and 70b, the optical axes of the optical deflectors 73a and 73b are shifted to the right with respect to the axis of the processing light EL, so the deflection angles of the angle-widening units 74a and 74b are larger on the right side, and the processing light EL is directed rightward. In the right-side beam scanning units 70d and 70e, the optical axes of the angle-widening units 74d and 74e are shifted to the left with respect to the optical axis of the processing light EL, so the deflection angles of the angle-widening units 74d and 74e are larger on the left side, and the processing light EL is directed leftward.

[0090] Therefore, in the beam scanning device 7 of the eighth embodiment, the beams emitted from the beam scanning units 70a to 70e are concentrated below the central beam scanning unit 70c. In the beam scanning device 7 of the eighth embodiment, the irradiation areas of the multiple beam scanning units 70 can be overlapped, similar to the beam scanning device 7 of the seventh embodiment, to perform efficient processing, even if the laser scanning units 70a to 70e are not arranged at an angle so that their optical axes face the irradiation areas.

[0091] In addition, although the beam scanning device 7 of the eighth embodiment has been shown as an example having a plurality of beam scanning units 70a to 70e arranged along one direction, the beam scanning device 7 of the eighth embodiment may also have a plurality of beam scanning units arranged two-dimensionally.

[0092] Ninth Embodiment Next, a beam scanning device according to a ninth embodiment will be described. The basic configuration of the beam scanning device according to the ninth embodiment is the same as that of the beam scanning device 7 according to the first embodiment. In the beam scanning device 7 according to the first embodiment, the optical deflector 73 deflects the beam in the yz plane by a variable deflection angle, but the beam scanning device 7 according to the ninth embodiment deflects the beam in the xz plane by a variable deflection angle in addition to deflecting the beam in the yz plane.

[0093] 20 is a diagram showing the configuration of an optical deflector 73 used in a beam scanning device according to the ninth embodiment. The optical deflector 73 includes a first optical deflector 73f that deflects light within the zx plane and a second optical deflector 73g that deflects light within the yz plane. The light exit surface of the first optical deflector 73a and the second optical deflector 73g are arranged so that the light exit surface of the first optical deflector 73f faces the light entrance surface of the second optical deflector 73g.

[0094] The first optical deflector 73f and the second optical deflector 73g have the same configuration as the optical deflector 73 of the first embodiment. That is, the optical deflectors 73f and 73g have a substantially rectangular parallelepiped KTN crystal with metal electrode films attached to two opposing surfaces across the optical axis. Applying a signal voltage to the two metal electrode films changes the refractive index of the KTN crystal, and light emitted from the KTN crystal is deflected with respect to the optical axis of the incident light. The first optical deflector 73f has metal electrode films attached to its top and bottom surfaces, while the second optical deflector 73g has metal electrode films attached to its front and back surfaces.

[0095] The beam scanning device of the ninth embodiment can deflect the beam in two directions with a variable deflection angle, and therefore can irradiate the beam at any position by deflecting the beam without moving the beam scanning device 7. Note that a cylindrical lens may be inserted on the incident surface side of the first optical deflector 73f or the incident surface side of the second optical deflector 73g, or a cylindrical lens may be inserted on both the incident surface side of the first optical deflector 73f and the incident surface side of the second optical deflector 73g.

[0096] 21 is a perspective view showing the configuration of a processing apparatus 2 according to a tenth embodiment. The processing apparatus 2 is an apparatus capable of forming a three-dimensional structure by performing additive processing. The processing apparatus 2 includes a material supply tank (not shown), a recoater 5, a modeling tank 6, and a beam scanning device 7. The recoater 5 supplies the modeling material M contained in the material supply tank 4 to the modeling tank 6 under the control of the control unit. The recoater 5 flattens the surface of the modeling material M supplied to the modeling tank 6, thereby forming a material layer ML, which is a layer of the modeling material M.

[0097] The beam scanning device 7 is a beam scanning device that scans a beam, and can have the same configuration as the beam scanning device 7 in the above-described embodiment. The beam scanning device 7 is movably attached to a gantry 10. The gantry 10 is movable in the x direction, and the beam scanning device 7 is movable in the y direction relative to the gantry 10. Therefore, the beam scanning device 7 can move in both the x direction and the y direction.

[0098] Figure 22 is a view of the beam scanning device 7 and its peripheral configuration as viewed from the y direction. The beam scanning device 7 has multiple beam scanning units 70 inside a housing. The beam scanning units 70 have the configurations described in Figures 15 and 16, for example. The beam scanning device 7 has a gas inlet 101 that feeds gas to adjust the temperature inside the housing, and a gas outlet 102 that exhausts gas from the housing. The bottom surface of the modeling tank 6 is an elevation stage 61. The elevation stage 61 moves up and down (in the Z-axis direction) by a drive mechanism under the control of a control unit.

[0099] 23 is a diagram showing how the processing device 2 moves the irradiation range when processing a structure larger than the irradiation range. The processing device 2 performs processing for each region of a predetermined range. The predetermined range may be smaller than the irradiation range of the beam scanning device 7.

[0100] First, the processing device 2 processes region R1, and when processing of region R1 is complete, the beam scanning device 7 moves in the y direction and stops temporarily, then processes region R2. Figure 23 shows the state after processing of region R2 is completed. After that, the processing device 2 moves the beam scanning device 7 in the y direction and stops temporarily, then processes region R3. Next, the processing device 2 moves the gantry 10 in the x direction and stops temporarily, then processes region R4. In this way, by moving the gantry 10 and the beam scanning device 7, different regions are sequentially processed. Note that in the description of Figure 23, the beam scanning device 7 is stationary during the processing period by the beam scanning device 7, but processing may also be performed while the beam scanning device 7 is moving.

[0101] 24 is a diagram showing the configuration of a processing apparatus according to an eleventh embodiment. The processing apparatus includes a vertical articulated robot 111 having a plurality of joints, and a movable mold manufacturing unit 112 attached to the tip of the vertical articulated robot 111. An example of such a vertical articulated robot 111 is described in U.S. Patent No. 11,548,217, and the description of U.S. Patent No. 11,548,217 is incorporated herein by reference.

[0102] The movable mold manufacturing unit 112 includes a material supply unit that supplies the modeling material and multiple scanner units that irradiate the modeling material with a laser. The material supply unit supplies the modeling material to a predetermined position moved by the vertical articulated robot 111. The multiple scanner units have the configurations described in Figures 15 and 16. The scanner units generate a structure by irradiating the modeling material supplied by the material supply unit with a beam. This configuration makes it possible to generate a structure at a desired location.

[0103] Although the beam scanning device and processing device according to the present disclosure have been described in detail above by way of exemplary embodiments, the present disclosure is not limited to the above-described exemplary embodiments.

[0104] REFERENCE SIGNS LIST 1 Processing system 2 Processing device 3 Control unit 4 Material supply tank 5 Recoater 6 Modeling tank 7 Beam scanning device 71 Focus unit 72 Condenser lens 73 Optical deflector 74 Wide-angle unit 75 Zoom lens 76 Dichroic mirror 77 Input lens 78 Mirror 79 Beam splitter 8 Light source 9 Monitor 101 Gas inlet 102 Gas outlet 111 Vertical articulated robot 112 Movable manufacturing unit

Claims

1. A beam scanning device for use in a processing device, comprising: a transmissive optical deflector into which a beam from a light source is incident and which can change the deflection angle of the emitted beam; and a magnifying optical system which magnifies the deflection angle of the beam emitted from the optical deflector.

2. A beam scanning device according to claim 1, further comprising a focusing device arranged in the optical path on the light source side of the optical deflector, for moving the focusing position along the propagation direction of the beam.

3. A beam scanning device according to claim 2, wherein said focusing device moves said focusing position of the beam in accordance with said deflection angle of the beam from said optical deflector.

4. A beam scanning device according to any one of claims 1 to 3, wherein the magnifying optical system includes a first lens group having positive power and a second lens group having negative power disposed between the first lens group and the optical deflector.

5. A beam scanning device according to claim 4, wherein the obliquely incident light beam that is obliquely incident on said second lens group from said optical deflector is incident on said second lens group at a position away from the optical axis of said magnifying optical system.

6. A beam scanning device as described in claim 4 or 5, wherein the divergence angle of the obliquely incident light beam that is obliquely incident from the second lens group to the first lens group and then emerges from the first lens group is smaller than the divergence angle of the obliquely incident light beam that is obliquely incident from the second lens group to the first lens group.

7. A beam scanning device according to any one of claims 4 to 6, wherein the distance from the optical axis of the magnifying optical system to the chief ray of the obliquely incident light beam that is obliquely incident from the optical deflector to the second lens group is smaller than the distance from the optical axis of the obliquely incident light beam that is obliquely incident from the second lens group to the first lens group.

8. A beam scanning device according to any one of claims 4 to 7, wherein the magnifying optical system has a third lens group having positive power and disposed between the second lens group and the optical deflector.

9. A beam scanning device according to claim 8, wherein said third lens group brings the light beam incident from said third lens group into a convergent state.

10. A beam scanning device according to claim 8 or 9, wherein the distance between said optical deflector and said third lens group is narrower than the distance between said third lens group and said second lens group.

11. A beam scanning device according to any one of claims 8 to 10, wherein the distance from the optical axis of the magnifying optical system to the chief ray of the obliquely incident light beam that is emitted from the optical deflector and obliquely incident on the third lens group is smaller than the distance from the optical axis to the chief ray of the obliquely incident light beam that is obliquely incident from the third lens group to the second lens group.

12. A beam scanning device according to any one of claims 1 to 11, wherein the magnifying optical system has a positive power as a whole.

13. A beam scanning device according to any one of claims 1 to 12, further comprising a condenser lens on the light incident side of said optical deflector.

14. A beam scanning device according to any one of claims 1 to 13, comprising a housing that houses the optical deflector and the magnifying optical system and has a dimension along a direction intersecting the optical axis of the magnifying optical system that is smaller than the dimension along the optical axis of the magnifying optical system.

15. A beam scanning device according to any one of claims 1 to 14, comprising a solid-state laser that emits a beam onto the optical deflector.

16. A processing device comprising the beam scanning device according to any one of claims 1 to 15, for processing an object using a beam from the beam scanning device.

17. A processing apparatus comprising a plurality of beam scanning devices according to any one of claims 1 to 15, for processing an object using beams from the plurality of beam scanning devices, wherein the plurality of beam scanning devices are arranged in a direction intersecting the optical axis.

18. A processing method comprising: irradiating an object with a beam from a beam scanning device according to any one of claims 1 to 15; and scanning the beam on the object.

Images