Method for producing stereolithographic article and stereolithography device

Abstract

The objective of the present disclosure is to enhance resolution in at least a propagation direction of promotion light in a stereolithographic technique using a liquid phase polymerization method. A stereolithographic method according to the present disclosure includes: a region defining step (S11) of defining a first region to be irradiated with promotion light on a molding surface set inside a photocurable resin and a second region to be irradiated with inhibition light; and an irradiation step (S13) of irradiating the first region with the promotion light having a wavelength λ1 which is n times (n is an integer of 2 or more) greater than a first absorption wavelength included in the absorption band of the polymerization initiator, and irradiating the second region with the inhibition light having a wavelength λ2 which is a second absorption wavelength included in the absorption band of the polymerization inhibitor. In the irradiation step, the polymerization initiator is activated by n-photon absorption of photons of the promotion light.

Description

Optically shaped object manufacturing method and optically shaped object manufacturing device

[0001] The present invention relates to a method and an apparatus for manufacturing a stereolithography object using a two-wavelength stereolithography method.

[0002] For example, as described in Patent Document 1, a stereolithography device (referred to as a three-dimensional modeling device in Patent Document 1) using a liquid-phase polymerization method is known. In a stereolithography device using a liquid-phase polymerization method, (1) a liquid vat is filled with a photocurable resin (ultraviolet-curable resin in Patent Document 1) containing a polymerization initiator and a monomer, (2) the polymerization initiator is activated by irradiating the liquid vat with light (ultraviolet light in Patent Document 1) focused at a point at a predetermined depth within the liquid vat, and (3) the activated polymerization initiator initiates a polymerization reaction between the monomer and the polymer. As a result, the irradiated photocurable resin hardens from a liquid to a solid, thereby forming a stereolithography object (see, for example, Figure 1 of Patent Document 1). Hereinafter, the light that activates the polymerization initiator is referred to as acceleration light.

[0003] In such a photolithography technique, there is a demand for increasing the resolution of the photolithography object and for forming a photolithography object of smaller size. On the other hand, the spot diameter of the light (here, the acceleration light) cannot be narrowed beyond the diffraction limit. Therefore, in such a photolithography technique, there is a limit to the resolution and the size of the photolithography object due to the diffraction limit.

[0004] To overcome this limit, for example, the two-wavelength stereolithography described in Non-Patent Document 1 employs a configuration in which a ring-shaped pattern of inhibitory light is superimposed on a spot of promoting light, as shown in Fig. 1. This configuration allows the diameter of the stereolithography object to be reduced beyond the diffraction limit.

[0005] The dual-wavelength stereolithography described in Non-Patent Document 1 is intended to produce only two-dimensional stereolithography objects. However, as shown in Figure 2(e) of Patent Document 1, it is possible to form a three-dimensional stereolithography object by sequentially stacking two-dimensional stereolithography objects in a layer-by-layer manner.

[0006] International Publication No. 2017 / 170475

[0007] Timothy F. Scott et. al., "Two-Color Single-Photon Photoinitiation and Photoinhibition for Subdiffraction Photolithography", Science, Vol. 324, p.913, 2009.

[0008] As described above, the acceleration light used in the two-wavelength stereolithography method is focused at a focal point located at a predetermined depth inside the liquid vat, and is a converging light in the area in front of the focal point and a diverging light in the area behind the focal point. Therefore, when viewed along the propagation direction of the acceleration light, the power density of the acceleration light increases as one approaches the focal point, reaches a maximum at the focal point, and decreases as one moves away from the focal point. Thus, when viewed along the propagation direction of the acceleration light, the power density of the acceleration light continuously changes depending on the distance from the focal point. Therefore, in the photocurable resin present in the area through which the acceleration light has passed, the polymerization reaction proceeds in accordance with the power density of the acceleration light, regardless of whether the area is located at the focal point or not.

[0009] Therefore, the two-wavelength stereolithography method has the problem that it is difficult to improve the resolution in the propagation direction of the acceleration light. This problem becomes more pronounced when a three-dimensional stereolithography object is formed by repeatedly irradiating the acceleration light for each layer in a layer-by-layer manner. This is because the acceleration light is divergent in the area behind the focal point, which causes unexpected curing of the photocurable resin in this area (the layer already formed in the previous turn), resulting in a change in the shape of the stereolithography object from the desired shape.

[0010] One aspect of the present invention has been made in view of the above-mentioned problems, and an object of the present invention is to improve the resolution at least in the propagation direction of the promotion light in a stereolithography technique using a liquid phase polymerization method.

[0011] As mentioned above, the power density changes continuously depending on the distance from the focal point, not only for the promotion light but also for the inhibition light. However, in the case of the inhibition light, even if it is irradiated on an area other than the desired area, it only inhibits the curing of the photocurable resin, so the resolution problem is unlikely to become apparent.

[0012] In order to solve the above-mentioned problems, one aspect of the present invention provides a method for manufacturing a stereolithographic object, which forms a stereolithographic object by irradiating a photocurable resin containing a monomer, a polymerization initiator, and a polymerization inhibitor with acceleration light and inhibitory light having different wavelengths, the method including: a region setting step for setting a first region to be irradiated with the acceleration light and a second region to be irradiated with the inhibitory light on a modeling surface set within the photocurable resin; and an irradiation step for irradiating the first region with acceleration light having a wavelength λ1 that is n times (n is an integer of 2 or more) a first absorption wavelength that is included in the absorption band of the polymerization initiator, and irradiating the second region with inhibitory light having a wavelength λ2 that is a second absorption wavelength that is included in the absorption band of the polymerization inhibitor, wherein at least a portion of the second region is in contact with or overlaps with a portion of the first region; and wherein in the irradiation step, the polymerization initiator is activated by absorbing n photons of the acceleration light.

[0013] In order to solve the above-mentioned problems, one aspect of the present invention provides a photo-lithography apparatus that forms a photo-modeled object by irradiating a photo-curable resin containing a monomer, a polymerization initiator, and a polymerization inhibitor with acceleration light and inhibitory light having different wavelengths, and includes: a region setting unit that sets a first region to be irradiated with the acceleration light and a second region to be irradiated with the inhibitory light on a modeling surface set inside the photo-curable resin; and an irradiation unit that irradiates the first region with acceleration light whose wavelength λ1 is n times (n is an integer of 2 or more) the absorption wavelength included in the absorption band of the polymerization initiator, and irradiates the second region with inhibitory light whose wavelength λ2 is an absorption wavelength included in the absorption band of the polymerization inhibitor, wherein at least a portion of the second region is in contact with or overlaps with a portion of the first region; and the polymerization initiator is activated by absorbing n photons of the acceleration light.

[0014] According to one aspect of the present invention, in a stereolithography technique using a liquid phase polymerization method, it is possible to improve the resolution at least in the propagation direction of the promotion light.

[0015] 1A is a schematic diagram showing the configuration of a photo-fabrication apparatus according to a first embodiment of the present invention, and is a schematic diagram illustrating the optical path of an acceleration light; FIG. 1B is a block diagram of a control unit included in the photo-fabrication apparatus shown in FIG. 1A is a schematic diagram showing the configuration of a photo-fabrication apparatus according to a first embodiment of the present invention, and is a schematic diagram illustrating the optical path of an inhibition light; FIG. 1A is a plan view showing the irradiation patterns of acceleration light and inhibition light imaged on the modeling surface of the exposure apparatus shown in FIG. 1 and FIG. 2; FIG. 1B is a graph showing the intensity distribution of the acceleration light and inhibition light shown in FIG. 1A; FIG. 1C is a plan view showing a modified example of the irradiation pattern of acceleration light and inhibition light shown in FIG. 1A; and FIG. 1D is a graph showing the intensity distribution of a modified example of the irradiation pattern of acceleration light and inhibition light shown in FIG. 1C. (a) and (b) are contour diagrams showing the correlation between the promoting light intensity, the inhibiting light intensity, and the degree of polymerization estimated from the promoting light intensity and the inhibiting light intensity. (c) and (d) are contour diagrams showing the correlation between the promoting light intensity and the inhibiting light intensity and the degree of polymerization estimated from the promoting light intensity and the inhibiting light intensity. ２ 7 is a graph showing the correlation between the acceleration light intensity and the estimated degree of polymerization obtained when the acceleration light wavelength λ1 is set to 460 nm, and (b) and (d) are the correlations when the acceleration light wavelength λ1 is set to 920 nm. It should be noted that (a) and (c) show the correlations when the acceleration light wavelength λ1 is set to 460 nm, and (b) and (d) show the correlations when the acceleration light wavelength λ1 is set to 920 nm. It is a flowchart of a method for manufacturing a stereolithography object according to a second embodiment of the present invention. It is a schematic diagram showing the configuration of a stereolithography apparatus according to a third embodiment of the present invention. It is a plan view showing the irradiation patterns of acceleration light and inhibitory light imaged on the modeling surface of a stereolithography apparatus according to a fourth embodiment of the present invention. It is a graph showing the intensity distributions of the acceleration light and inhibitory light shown in (a). It is a graph in which the oxygen concentration distribution and oxygen flow rate distribution are added to the graph shown in (b) of FIG.

[0016] First Embodiment A stereolithography apparatus 1 according to a first embodiment of the present invention will be described with reference to FIGS.

[0017] 1A is a schematic diagram illustrating the configuration of the optical shaping apparatus 1 and is a schematic diagram illustrating the optical path of the promotion light L1. FIG. 1B is a block diagram of a control unit C included in the optical shaping apparatus 1.

[0018] FIG. 2 is a schematic diagram showing the configuration of the optical shaping apparatus 1, and is a schematic diagram for explaining the optical path of the inhibiting light L2.

[0019] 3A is a plan view showing the irradiation pattern of the acceleration light L1 and the inhibitory light L2 formed on the forming surface P of the optical shaping apparatus 1, and FIG. 3B is a graph showing the intensity distribution of the acceleration light L1 and the inhibitory light L2. Note that FIG. 3B illustrates the intensity distribution along the line A-A' shown in FIG. 3A. FIG. 3C is a plan view showing a modified example of the irradiation pattern of the acceleration light L1 and the inhibitory light L2 shown in FIG. 3A. FIG. 3D is a graph showing the intensity distribution of a modified example of the irradiation pattern of the acceleration light L1 and the inhibitory light L2. Note that FIG. 3D illustrates the intensity distribution along the line A-A' shown in FIG. 3C. FIG. 3B is a plan view showing the irradiation pattern of the acceleration light L1 and the inhibitory light L2 formed on the forming surface P of the optical shaping apparatus 1, and FIG. 3B is a graph showing the intensity distribution of the acceleration light L1 and the inhibitory light L2. FIG. 3(b) shows the intensity distribution along the line AA' shown in FIG. 2(3).

[0020] 4(a) and (b) are contour diagrams showing the correlation between the promoting light intensity, the inhibiting light intensity, and the degree of polymerization estimated from the promoting light intensity and the inhibiting light intensity. FIG. 4(c) and (d) are contour diagrams showing the correlation between the promoting light intensity and the inhibiting light intensity and the degree of polymerization estimated from the promoting light intensity and the inhibiting light intensity. ２ 4A and 4C show the correlation between the promotion light intensity and the estimated degree of polymerization when the promotion light wavelength λ1 is 460 nm (i.e., when the polymerization initiator is activated by single-photon absorption), while FIG. 4B and 4D show the correlation when the promotion light wavelength λ1 is 920 nm (i.e., when the polymerization initiator is activated by two-photon absorption).

[0021] The optical shaping apparatus 1 is an optical shaping apparatus that uses a liquid-phase polymerization method. In this embodiment, 1,4-butanediol dimethylacrylate is used as a monomer that constitutes the liquid photocurable resin R before curing. Camphorquinone is used as a polymerization initiator that absorbs the energy of the acceleration light L1 when irradiated with the acceleration light L1 and starts the polymerization reaction. However, the combination of the polymer and the polymerization initiator is not limited to 1,4-butanediol dimethylacrylate and camphorquinone, and can be appropriately selected from existing combinations. Furthermore, ethyl 4-(dimethylamino)benzoate may be further added to accelerate the polymerization reaction.

[0022] Camphorquinone, used as a polymerization initiator, has an absorption band for activation (more specifically, radicalization) in the range of 400 nm to 500 nm. Therefore, in this embodiment, 460 nm, which is included in the absorption band of 400 nm to 500 nm, is defined as the first absorption wavelength, and infrared light with a wavelength λ1 twice the first absorption wavelength (i.e., 920 nm) is used as the acceleration light L1. In this case, the polymerization initiator is activated by two-photon absorption of the acceleration light L1. However, the wavelength λ1 of the acceleration light L1 may be n times the first absorption wavelength (n is an integer greater than or equal to 2), and the polymerization initiator may be activated by absorbing n photons of the acceleration light L1. Note that n is not limited to 2. However, the probability that the acceleration light L1 is absorbed by the polymerization initiator decreases exponentially as n increases. Therefore, n can be determined appropriately depending on the intensity of the acceleration light L1, the area of ​​the first region (described below), the absorption coefficient at wavelength λ1, and the like. Suitable examples of n include 2 or 3.

[0023] In one aspect of the present invention, the wavelength λ1 is preferably the wavelength at which multiphoton absorption is most likely to occur. This configuration allows for efficient multiphoton absorption. In this case, the first absorption wavelength, which is 1 / n of the wavelength λ1, is often different from the peak wavelength in the absorption band of the polymerization initiator (camphorquinone in this embodiment). This is because, when activating a polymerization initiator using multiphoton absorption (two-photon absorption in this embodiment), the absorption process of the polymerization initiator passes through a transient state (a state in which only one photon is absorbed). The band structure of the polymerization initiator that has absorbed one photon changes slightly from the band structure of the polymerization initiator in its ground state. Therefore, the peak wavelength in the absorption band of the polymerization initiator in its transient state shifts from the peak wavelength in the absorption band of the polymerization initiator in its ground state.

[0024] The amount of this shift in the peak wavelength is generally 100 nm or less. Therefore, the wavelength at which multiphoton absorption is most likely to occur is often different from n times the peak wavelength in the absorption band of the polymerization initiator in the ground state. In other words, when the wavelength at which multiphoton absorption is most likely to occur is used as the wavelength λ1, the first absorption wavelength corresponding to 1 / n of that wavelength is often slightly different from the peak wavelength in the absorption band of the polymerization initiator in the ground state.

[0025] Tetraethylthiuram disulfide, which is used as a polymerization inhibitor, has an absorption band for activation (more specifically, radicalization) of 200 nm to 450 nm. Therefore, in this embodiment, ultraviolet light with a wavelength λ2 of 365 nm is used as the inhibitory light L2.

[0026] 1A, the optical shaping apparatus 1 includes a light source 11, a condenser lens 12, a DMD (Digital Mirror Device) 13, a tube lens 14, a mirror 15, an objective lens 16, a light source 21, a condenser lens 22, a DMD 23, a mirror 24, a dichroic mirror 25, and a control unit C. The optical shaping apparatus 1 also includes a stage not shown in FIG.

[0027] The light source 11, condenser lens 12, and DMD 13 act on the promotion light L1, while the light source 21, condenser lens 22, and DMD 23 act on the inhibition light L2. The dichroic mirror 25 combines the promotion light L1 and the inhibition light L2. The tube lens 14, mirror 15, and objective lens 16 act on both the combined promotion light L1 and inhibition light L2.

[0028] The stage is a stage on whose mounting surface a liquid vat B filled with photocurable resin R is placed, and is a stage that can move in translation parallel to the three axial directions of a Cartesian coordinate system. The stage may be configured to be rotatable about an axis that is parallel to the perpendicular to the mounting surface.

[0029] The controller C controls the irradiation pattern of the acceleration light L1 that forms an image on the printing surface P (described later) by switching the state of each micromirror that constitutes the DMD 13 (described later) between an ON state and an OFF state. Similarly, the controller C controls the irradiation pattern of the inhibitory light L2 that forms an image on the printing surface P (described later) by switching the state of each micromirror that constitutes the DMD 23 (described later) between an ON state and an OFF state. Hereinafter, the irradiation pattern of the acceleration light L1 that forms an image on the printing surface P will also be referred to as the first region A1, and the irradiation pattern of the inhibitory light L2 that forms an image on the printing surface P will also be referred to as the second region A2 (see FIGS. 3A to 3D and 7A and 7B). The controller C also controls the depth direction position of the printing surface P within the photocurable resin R by moving the positions of the tube lens 14 and the objective lens 16 (described later). The controller C also controls the position of the stage.

[0030] (Irradiation Unit for Accelerating Light) First, the irradiation unit that acts on the acceleration light L1 will be described with reference to FIG.

[0031] The light source 11 is a light source that generates acceleration light L1. The wavelength λ1 of the acceleration light L1 may be n times (n is an integer of 2 or more) a predetermined first absorption wavelength included in the absorption band of the polymerization initiator, and may be appropriately selected depending on the predetermined first absorption wavelength selected within the absorption band. The first absorption wavelength may be selected within the absorption band depending on the magnitude of the absorption coefficient of the polymerization initiator, the specifications of the light source 11, and the like.

[0032] In this embodiment, as described above, the first absorption wavelength is set to 460 nm, and infrared light having a wavelength λ1 twice the first absorption wavelength (i.e., 920 nm) is used as the acceleration light L1. The wavelength λ1 may be defined as the center wavelength in the spectrum of the acceleration light L1. The spectral full width at half maximum of the peak including the wavelength λ1 in the spectrum of the acceleration light L1 is not limited. When using an irradiation unit that is a 4f optical system, such as the optical shaping apparatus 3 described with reference to FIG. 6 in the third embodiment, the spectral full width at half maximum of the peak including the wavelength λ1 is preferably 5 nm or more and 1000 nm or less.

[0033] In this embodiment, the light source 11 is an LED array in which multiple light emitting diodes (LEDs) are arranged in a matrix. The light source 11 is configured to emit convergent light from a light-emitting region 111 having a predetermined area. However, the form of the light source 11 is not limited to an LED array and can be designed as appropriate. For example, a laser can be used as the light source 11 instead of an LED. When a laser is used as the light source 11, the light source 11 may be a continuous wave (CW) laser that oscillates continuously or a pulsed laser that oscillates in pulses. When a pulsed laser is used as the light source 11, the pulse width of the promotion light L1 is not limited and can be appropriately determined depending on the power of the promotion light L1 emitted by the light source 11. In an ultrashort pulse laser, the narrower the pulse width of the oscillated laser light, the wider the spectral full width at half maximum of the oscillated laser light. Therefore, when an irradiation unit that is a 4f optical system, such as the stereolithography device 3, is used, the pulse width of the oscillated laser light can be adjusted to achieve a configuration in which the spectral full width at half maximum of the peak including the wavelength λ1 is within a range of 5 nm to 1000 nm. In particular, when an ultrashort pulse laser is used, the wavelength band of the promotion light L1 becomes broad. As a result, a reaction may be initiated by one-photon absorption, or the wavelength band of the promotion light L1 may overlap with the absorption band of the polymerization inhibitor. In such cases, unnecessary wavelengths of the promotion light L1 may be removed using, for example, a frequency filter, a band-cut filter, or a band-pass filter.

[0034] In Fig. 1 , among the chief rays constituting the convergent light emitted from the light-emitting region 111 of the light source 11, representative chief rays L11, L12, and L13 are shown by dashed-dotted lines. The chief ray L11 is a light ray emitted from the center of the light-emitting region 111 toward the normal direction of the light-emitting region 111. Note that in Fig. 1 , a light beam L11F represented by the chief ray L11 is shown by solid lines and hatching. The light beam L11F can be considered to be a light beam emitted from a point light source located in the center of the light-emitting region 111, and is a light beam that diverges at the time of emission. The chief rays L12 and L13 are light rays emitted from the outer edge of the light-emitting region 111, and are light rays that converge to approach the chief ray L11 at the time of emission. Similar to the light beam L11F corresponding to the chief ray L11, there are light beams corresponding to the chief ray L12 and the chief ray L13, but these light beams are not shown in FIG.

[0035] Although not shown in FIG. 1 , the light source 11 may further include optical elements such as a diffuser (or integrator lens), a collector lens, and an aperture stop arranged downstream of the LED array in order to emit promotion light L1 whose chief ray becomes convergent light. These optical elements may be arranged inside or outside the housing of the light source 11. The types, number, and arrangement of these optical elements are not limited and can be designed as appropriate.

[0036] The condenser lens 12 is a convex lens that converts the luminous flux L11F, which is divergent light, into convergent light and focuses the promotion light L1 emitted from the light-emitting region 111 onto the light-receiving surface of the DMD 13.

[0037] The DMD 13 is an example of a spatial light modulator, and its light receiving surface is composed of a plurality of micromirrors arranged in a matrix. An example of a spatial light modulator other than a DMD is a liquid crystal on silicon (LCOS). When an LCOS is used as the spatial light modulator, the LCOS may be either a reflective type or a transmissive type.

[0038] In the DMD 13, the propagation direction of the acceleration light L1 incident on each micromirror is switched by switching the direction of the reflective surface of each micromirror. In this embodiment, as shown in Figure 1, the state in which the acceleration light L1 reflected by each micromirror travels toward the tube lens 14, mirror 15, and objective lens 16 is called the "on state," and states other than the "on state" are called the "off state." Only when a certain micromirror is in the "on" state, the acceleration light L1 reflected by that micromirror is imaged on the modeling surface P set inside the photocurable resin R.

[0039] The DMD 13 switches the state of each micromirror between an on state and an off state in response to a control signal generated by the controller C, thereby generating an irradiation pattern when irradiating the acceleration light L1 onto the printing surface P. The DMD 13 also controls the duty ratio, which is the ratio between the time that each micromirror is in the on state and the time that each micromirror is in the off state, to control the intensity of the acceleration light in the area of ​​the printing surface P that corresponds to that micromirror.

[0040] Here, the irradiation pattern shown in Figure 3 is used as an example of the irradiation pattern of the acceleration light L1. As shown in Figures 3(a) and 3(b), the DMD 13 irradiates the first region A1 of the printing surface P with acceleration light L1 whose time-averaged intensity is higher than the printing threshold Th. The DMD 13, together with the tube lens 14 and objective lens 16 described below, constitutes part of the irradiation unit. Note that the printing threshold Th is not a threshold value that determines whether or not the monomer will initiate a polymerization reaction, but rather a threshold value that determines whether or not the polymer generated by the polymerization reaction will flow away in a subsequent cleaning process and remain fixed in the intended position as a stereolithographic object.

[0041] The modeling threshold Th can be determined appropriately depending on the types of monomer, polymerization initiator, and polymerization inhibitor used as the photocurable resin, the wavelength λ1 of the acceleration light L1, the wavelength λ2 of the inhibition light L2, etc. Specifically, a correlation such as that shown in FIG. 4B is created in advance, and the modeling threshold Th can be determined based on this correlation. The correlation can be created based on simulation results or experimental results. In this embodiment, the acceleration light intensity and inhibition light intensity that result in an estimated degree of polymerization of 70% based on the correlation shown in FIG. 4B are used as the modeling threshold Th. However, the estimated degree of polymerization used as the basis for determining the modeling threshold Th is not limited to 70% and can be determined appropriately. An example of a preferred range for the estimated degree of polymerization is 60% or more and 80% or less.

[0042] In this irradiation pattern, the first region A1 is a region in which the outer edge A11 is a square, and the second region A2 is a region in which the outer edge A21 and the inner edge A22 are each square. As can be seen from (a) and (b) of Figures 3A and 3B, in this irradiation pattern, the outer edge A21 surrounds the outer edge A11. Also, in this irradiation pattern, the inner edge A22 surrounds the outer edge A11 while being in contact with the outer edge A11. Hereinafter, the time-averaged intensity of the promotion light L1, rather than the instantaneous intensity of the promotion light L1 at a certain point in time, is referred to as the promotion light intensity.

[0043] The shapes of the first region A1 and the second region A2 are not limited to those shown in (a) and (b) of Figure 3, and it is sufficient that at least a part of the second region A2 contacts or overlaps with a part of the first region A1. The irradiation patterns shown in (a) and (b) of Figure 3 are an example of a case where the inner edge A22 of the second region A2 contacts the outer edge A11 of the first region A1.

[0044] 3A and 3B, the inner edge A22 is positioned inside the outer edge A11 (i.e., the inner edge A22 is surrounded by the outer edge A11). This irradiation pattern is an example of a case where a part of the second region A2 overlaps a part of the first region A1.

[0045] 3(c) and 3(d) are also examples of modified irradiation patterns. In these modified irradiation patterns, the outer edge A21 and the outer edge A11 coincide with each other, and the inner edge A22 is surrounded by the outer edge A11. This modified irradiation pattern is an example of a case where the entire second region A2 overlaps the first region A1.

[0046] Furthermore, the first region A1 and the second region A2 may be an irradiation pattern in which the first region A1 is not surrounded by the second region A2, as long as at least a portion of the second region A2 contacts or overlaps with a portion of the first region A1. An example of such an irradiation pattern may be an irradiation pattern corresponding to a line-and-step pattern in which strip-shaped stereolithographic objects are arranged in parallel at a predetermined interval. In this case, the strip-shaped first region A1 and the strip-shaped second region A2 may be alternately arranged. The strip-shaped first region A1 and the strip-shaped second region A2 may be arranged such that the long sides of the adjacent first region A1 and second region A2 contact each other, or such that a portion of the first region A1 and a portion of the second region A2 overlap.

[0047] The tube lens 14 is a convex lens that collimates the acceleration light L1 having a desired pattern, which is reflected by the DMD 13. The tube lens 14 also cooperates with the objective lens 16 when changing the working distance of the objective lens 16 (described later) to control the depthwise position of the modeling surface P within the photocurable resin R. More specifically, the tube lens 14 adjusts the distance from the DMD 13 in synchronization with changes in the working distance of the objective lens 16, thereby adjusting the modeling surface P and the DMD 13 (more specifically, the light-receiving surface of the DMD 13) to be conjugate with respect to the tube lens 14 and the objective lens 16. In FIGS. 1 and 2 , the modeling surface P and the DMD 13, which are conjugate with respect to the tube lens 14 and the objective lens 16, are indicated by filled triangles.

[0048] The mirror 15 is a mirror that bends the optical path of the promotion light L1 collimated by the tube lens 14 by reflecting it.

[0049] The objective lens 16 is a convex lens that is spatially intensity modulated by the DMD 13 and focuses the acceleration light L1 having a desired pattern onto the modeling surface P. The objective lens 16 adjusts the working distance from the photocurable resin R contained in the liquid tank B, thereby adjusting the depthwise position of the modeling surface P within the photocurable resin R. By being able to adjust the depth, the stereolithography device 1 can perform three-dimensional stereolithography using a liquid phase polymerization method.

[0050] As described above, the optical molding device 1 includes, as an irradiation unit, a DMD 13 (an example of a spatial light modulator) that generates the acceleration light L1 to be irradiated to the first area A1 and the acceleration light L1 to be irradiated to the second area A2 (an example of first light and second light) by spatially intensity-modulating the acceleration light L1 from the light source 11, and a tube lens 14 and an objective lens 16 (an example of a lens) that focus the acceleration light L1 to be irradiated to the first area A1 and the acceleration light L1 to be irradiated to the second area A2 onto the molding surface P, and the molding surface P and the DMD 13 are arranged in a conjugate position with respect to the tube lens 14 and the objective lens 16.

[0051] (Irradiation Unit of Inhibitory Light) Next, with reference to FIG. 2, an irradiation unit that acts on the inhibitory light L2 will be described.

[0052] The light source 21 generates the inhibiting light L2 (see FIG. 2). The wavelength λ2 of the inhibiting light L2 may be a second absorption wavelength included in the absorption band of the polymerization inhibitor contained in the photocurable resin. The second absorption wavelength (i.e., wavelength λ2) can be selected from within the absorption band of the polymerization inhibitor depending on the magnitude of the absorption coefficient of the polymerization inhibitor, the specifications of the light source 21, and the like.

[0053] In this embodiment, similar to the light source 11, the light source 21 is an LED array in which multiple LEDs (light emitting diodes) are arranged in a matrix. The light source 21 has the same configuration as the light source 11, except that the wavelength λ2 is 365 nm instead of 920 nm. That is, the chief ray L21, the chief ray L22, the chief ray L23, and the luminous flux L21F of the inhibition light L2 emitted by the light source 21 correspond to the chief ray L11, the chief ray L12, the chief ray L13, and the luminous flux L11F of the promotion light L1 emitted by the light source 11, respectively. Furthermore, the light-emitting region 211 of the light source 21 corresponds to the light-emitting region 111 of the light source 11. Therefore, a description of these chief rays and luminous fluxes will be omitted here.

[0054] The condenser lens 22 is a convex lens that converts the divergent light beam L21F into convergent light and focuses the inhibiting light L2 emitted from the light-emitting region 211 onto the light-receiving surface of the DMD 23 via the mirror 24.

[0055] The mirror 24 is a mirror that bends the optical path of the inhibiting light L2 converted into convergent light by the condenser lens 22 toward the DMD 23 by reflecting it.

[0056] The DMD 23 is another example of a spatial light modulator, and its light receiving surface is composed of a plurality of micromirrors arranged in a matrix. An example of a spatial light modulator other than a DMD is a liquid crystal on silicon (LCOS). When an LCOS is used as the spatial light modulator, the LCOS may be either a reflective type or a transmissive type.

[0057] The DMD 23 has the same configuration as the DMD 13, and is controlled by the control unit C. However, the DMD 23 generates an inhibiting light L2 having a different pattern from the promoting light L1.

[0058] 3A and 3C show the irradiation pattern of the acceleration light L1 generated by the DMD 13 on the printing surface P (i.e., the first region A1) and the irradiation pattern of the inhibition light L2 generated by the DMD 23 on the printing surface P (i.e., the second region A2). Also, 3B and 3D show the intensity distributions of the acceleration light L1 and the inhibition light L2. According to 7A and 7B, the irradiation pattern of the acceleration light L1 is the same as the irradiation pattern of the acceleration light L1 shown in FIG. 2. That is, the outer edge A21 of the second region A2 surrounds the outer edge A11 of the first region A1, and the inner edge A22 of the second region A2 surrounds the outer edge A11 while being in contact with the outer edge A11.

[0059] The shape of the second region A2 has been explained together with the shape of the first region A1 in the section (Irradiation portion of accelerating light), so the explanation thereof will be omitted here.

[0060] In this way, the DMD 23 irradiates the second area A2 with the inhibitory light having the wavelength λ2 (i.e., the second absorption wavelength) on the modeling surface P. The DMD 23, together with the tube lens 14 and objective lens 16 described above, constitutes a part of the irradiation unit.

[0061] (Irradiation Unit Common to Accelerating Light and Inhibitory Light) Next, an irradiation unit that acts commonly on the acceleration light L1 and the inhibitory light L2 will be described. Fig. 1 shows the optical path of the acceleration light L1, and Fig. 2 shows the optical path of the inhibitory light L2. The acceleration light L1 and the inhibitory light L2 are combined by the dichroic mirror 25 and imaged on the printing surface P using the tube lens 14 and the objective lens 16.

[0062] The dichroic mirror 25 transmits the promotion light L1 having a desired pattern that has been spatially intensity modulated by the DMD 13, and reflects the inhibition light L2 having a desired pattern that has been spatially intensity modulated by the DMD 23, thereby combining the promotion light L1 and the inhibition light L2 onto a common optical axis. To this end, the dichroic mirror 25 is configured so that the wavelength λ1 of the promotion light L1 (λ1 = 920 nm in this embodiment) is included in its transmission band, and the wavelength λ2 of the inhibition light L2 (λ2 = 365 nm in this embodiment) is included in its reflection band (see FIGS. 1 and 2).

[0063] The inhibiting light L2, which is combined with the promoting light L1 by the dichroic mirror 25 and has the desired pattern, is focused onto the forming surface P via the tube lens 14, mirror 15, and objective lens 16, which are arranged downstream of the dichroic mirror 25.

[0064] As described above, the optical molding device 1 includes the DMD 23 (an example of a spatial intensity modulator) that generates the inhibitory light L2 that is irradiated onto the second region A2 by spatially intensity modulating the inhibitory light L2 from the light source 21, and the tube lens 14 and objective lens 16 (an example of a lens) that focus the inhibitory light L2 irradiated onto the second region A2 onto the molding surface P, and the molding surface P and the DMD 23 are disposed in conjugate positions with respect to the tube lens 14 and the objective lens 16. Note that in Figures 1 and 2, the molding surface P and the DMD 23, which are in conjugate positions with respect to the tube lens 14 and the objective lens 16, are indicated by filled-in triangles.

[0065] In the stereolithography apparatus 1, a multiphoton absorption method (two-photon absorption method in this embodiment) is employed in the process of activating the polymerization initiator in a two-wavelength stereolithography method that uses both the acceleration light L1 and the inhibition light L2. Therefore, in this embodiment, the difference between the wavelength λ2 of the inhibition light L2 (365 nm in this embodiment) and the wavelength λ1 of the acceleration light L1 (920 nm in this embodiment) is significantly greater than when the polymerization initiator is activated using a single-photon absorption method. In this case, chromatic aberration is likely to occur between the acceleration light L1 and the inhibition light L2 due to the difference between the wavelengths λ1 and λ2. To reduce (preferably eliminate) this chromatic aberration, it is preferable to use an achromatic lens for at least one of the tube lens 14 and the objective lens 16. An achromatic lens designed to match the combination of the wavelengths λ1 and λ2 can reduce (preferably eliminate) this chromatic aberration.

[0066] <Summary of the photo-polymerization device> As described above, the photo-polymerization device 1 according to this embodiment is a photo-polymerization device (using a two-wavelength photo-polymerization method) that forms a photo-polymerized object by irradiating a photo-curable resin containing a monomer, a polymerization initiator, and a polymerization inhibitor with promotion light L1 and inhibition light L2 having different wavelengths (see FIGS. 1 and 2).

[0067] The DMD 13, the DMD 23, the tube lens 14, and the objective lens 16 constitute an irradiation unit of the optical shaping apparatus 1 (see FIGS. 1A and 2). The control unit C of the optical shaping apparatus 1 includes an area setting unit C1, an intensity setting unit C2, and an irradiation control unit C3 (see FIG. 1B).

[0068] The area setting unit C1 sets a first area A1 to be irradiated with the accelerating light L1 and a second area A2 to be irradiated with the inhibiting light L2 on the modeling surface P set inside the photocurable resin.

[0069] The irradiation unit irradiates the first region A1 with promotion light L1, whose wavelength λ1 is n times (n is an integer of 2 or more) the first absorption wavelength included in the absorption band of the polymerization initiator, and irradiates the second region A2 with inhibition light L2, whose wavelength λ2 is a second absorption wavelength included in the absorption band of the polymerization inhibitor.

[0070] As described above, at least a portion of the second region A2 is in contact with or overlaps a portion of the first region A1. The polymerization initiator is activated by absorbing n photons of the acceleration light L1.

[0071] In this embodiment, the optical shaping apparatus 1 has been described using the case where n=2.

[0072] In the optical molding apparatus 1, the irradiation unit preferably includes a lens (objective lens 16) that condenses the promotion light L1 and the inhibitory light L2, and a spatial light modulator (DMD 23) that converts the intensity distribution of the inhibitory light L2 to have a pattern corresponding to the second region A2, and the molding surface P and the spatial light modulator (DMD 23) are preferably disposed in a conjugate position with respect to the lens (objective lens 16). The inhibitory light L2, whose intensity distribution has been converted by the spatial light modulator (DMD 23), is irradiated onto the second region A2 on the molding surface P.

[0073] In addition, in the optical molding device 1, the irradiation unit further includes a spatial light modulator (DMD13) other than the spatial light modulator (DMD23) that converts the intensity distribution of the promotion light L1 to have a pattern corresponding to the first region A1, and the molding surface P and the other spatial light modulator (DMD13) are arranged in a conjugate position with respect to the lens, and the promotion light (L1) whose intensity distribution has been converted by the other spatial light modulator (DMD13) is irradiated onto the first region A1 on the molding surface P.

[0074] Furthermore, in the optical molding apparatus 1, the region setting unit C1 further sets a first polymerization degree, which is the target polymerization degree in the first region A1, and a second polymerization degree, which is the target polymerization degree in the second region A2, and the intensity setting unit C2 sets the intensity distribution of the promotion light L1 in the first region A1 and the intensity distribution of the inhibition light L2 in the second region A2 so that the estimated polymerization degree in the first region A1 is equal to or greater than the first polymerization degree and the estimated polymerization degree in the second region A2 is less than the second polymerization degree.

[0075] In the optical shaping apparatus 1, the first polymerization degree can be appropriately set within a range in which the polymer generated by the polymerization reaction does not flow during the cleaning process and is fixed at the intended position as a photo-modeled object. In the optical shaping apparatus 1, the second polymerization degree can be appropriately set within a range in which the polymer generated by the polymerization reaction does not remain as a photo-modeled object during the cleaning process and flows away. In the above-described embodiment, 70% is used as the estimated polymerization degree, and the promoting light intensity and inhibiting light intensity at which the estimated polymerization degree is 70% are used as the modeling threshold Th. In this case, the first polymerization degree and the second polymerization degree are both 70%. However, the first polymerization degree and the second polymerization degree are not limited to 70% and may be equal to each other, or the first polymerization degree may be greater than the second polymerization degree.

[0076] Furthermore, in the optical molding apparatus 1, it is preferable that the intensity setting unit C2 refers to the correlation between the promotion light intensity, which is the irradiation intensity of the promotion light L1, the inhibition light intensity, which is the irradiation intensity of the inhibition light L2, and the estimated degree of polymerization estimated from the promotion light intensity and the inhibition light intensity (see (b) of Figure 4), and sets the intensity distribution of the promotion light L1 in the first region A1 and the intensity distribution of the inhibition light L2 in the second region A2 so that the estimated degree of polymerization in the first region A1 is equal to or greater than the first degree of polymerization and the estimated degree of polymerization in the second region A2 is less than the second degree of polymerization.

[0077] The irradiation control unit C3 then (1) controls the output of the acceleration light L1 emitted by the light source 11 so that the intensity distribution of the acceleration light L1 in the first region A1 approaches (preferably coincides with) the intensity distribution set by the intensity setting unit C2, and (2) controls the output of the inhibition light L2 emitted by the light source 21 so that the intensity distribution of the inhibition light L2 in the second region A2 approaches (preferably coincides with) the intensity distribution set by the intensity setting unit C2. As a result, the polymerization initiator contained in the first region A1 of the printing surface P is activated by absorbing n photons of the acceleration light L1.

[0078] [Embodiment 2] A method M10 for manufacturing a photo-fabricated object according to embodiment 2 of the present invention will be described with reference to Fig. 5. Fig. 5 is a flowchart of the method M10 for manufacturing a photo-fabricated object. Note that, hereinafter, the method M10 for manufacturing a photo-fabricated object will also be simply referred to as manufacturing method M10.

[0079] Manufacturing method M10 is a manufacturing method that uses the optical shaping apparatus 1 described in embodiment 1. In other words, manufacturing method M10 is a manufacturing method for manufacturing a photo-modeled object using the optical shaping apparatus 1. Therefore, since manufacturing method M10 and the optical shaping apparatus 1 correspond to each other, in this embodiment, manufacturing method M10 will be described with reference to embodiment 1 and the corresponding relationship between manufacturing method M10 and the optical shaping apparatus 1.

[0080] Manufacturing method M10 is a method for manufacturing a photo-formed object (using a two-wavelength photo-formation method) by irradiating a photo-curable resin containing a monomer, a polymerization initiator, and a polymerization inhibitor with promotion light L1 and inhibition light L2 having different wavelengths to form a photo-formed object.

[0081] As shown in FIG. 5, the manufacturing method M10 includes an area setting step S11, an intensity setting step S12, and an irradiation step S13.

[0082] The region setting step S11 sets a first region A1 to be irradiated with the accelerating light L1 and a second region A2 to be irradiated with the inhibiting light L2 on the modeling surface P set inside the photocurable resin. The region setting step S11 corresponds to the region setting unit C1 shown in (b) of FIG.

[0083] In the irradiation step S13, the first region A1 is irradiated with promotion light L1 having a wavelength λ1 that is n times (n is an integer of 2 or more) a first absorption wavelength included in the absorption band of the polymerization initiator, and the second region A2 is irradiated with inhibition light L2 having a wavelength λ2 that is a second absorption wavelength included in the absorption band of the polymerization inhibitor. The irradiation step S13 corresponds to the irradiation unit of the stereolithography apparatus 1.

[0084] 3, at least a portion of the second region A2 is in contact with or overlaps a portion of the first region A1. The polymerization initiator is activated by absorbing n photons of the acceleration light L1.

[0085] In this embodiment, as in the first embodiment, the manufacturing method M10 will be described using the case where n=2.

[0086] In addition, in the irradiation step S13, the intensity distribution of the inhibitory light L2 is converted using a spatial light modulator (DMD 23) so that it has a pattern corresponding to the second region A2, and the inhibitory light L2 is irradiated onto the second region A2 on the modeling surface P.

[0087] In addition, in the irradiation process S13, the intensity distribution of the promotion light L1 is converted using a spatial light modulator (DMD13) other than the spatial light modulator (DMD23) so that it has a pattern corresponding to the first area A1, and the promotion light L1 is irradiated onto the first area A1 on the forming surface P.

[0088] In addition, in the manufacturing method M10, the intensity setting step S12 is performed between the region setting step S11 and the irradiation step S13. The intensity setting step S12 corresponds to the intensity setting unit C2 shown in FIG.

[0089] The region setting step S11 further sets a first polymerization degree, which is a target polymerization degree in the first region A1, and a second polymerization degree, which is a target polymerization degree in the second region A2.

[0090] The intensity setting process S12 sets the intensity distribution of the promotion light L1 in the first region A1 and the intensity distribution of the inhibition light L2 in the second region A2 so that the estimated degree of polymerization in the first region A1 is equal to or greater than the first degree of polymerization and the estimated degree of polymerization in the second region A2 is less than the second degree of polymerization.

[0091] In addition, in manufacturing method M10, the intensity setting process S12 refers to the correlation between the promotion light intensity, which is the irradiation intensity of promotion light L1, the inhibition light intensity, which is the irradiation intensity of inhibition light L2, and the estimated degree of polymerization estimated from the promotion light intensity and the inhibition light intensity (see (b) of Figure 4), and sets the intensity distribution of each of the promotion light L1 and the inhibition light L2.

[0092] [Embodiment 3] A photo-fabrication apparatus 3 according to embodiment 3 of the present invention will be described with reference to Fig. 6. Fig. 6 is a schematic diagram showing the configuration of the photo-fabrication apparatus 3. The photo-fabrication apparatus 3 is significantly different from the photo-fabrication apparatus 1 according to embodiment 1 in that it employs an irradiation unit that is a 4f optical system.

[0093] 6, the optical shaping apparatus 3 includes a light source 311, a condenser lens 321, a light source 312, a condenser lens 322, a diffraction grating 33, a condenser lens 34, an LCOS (Liquid Crystal On Silicon) 35, a condenser lens 36, a diffraction grating 37, an objective lens 38, and a controller C. In this embodiment, the corresponding components of the optical shaping apparatus 3 that correspond to those of the optical shaping apparatus 1 (see FIGS. 1 and 2) will be described, and differences, if any, will be described. In this embodiment, a description of components common to the optical shaping apparatus 1, such as the configuration of the photocurable resin, will be omitted.

[0094] The light source 311 corresponds to the light source 11 and emits promotion light L1. However, the light source 311 emits promotion light L1 having a wavelength λ1 included in the absorption band of the polymerization initiator and a spectral full width at half maximum of 10 nm. That is, in this embodiment, the promotion light L1 emitted by the light source 311 has a central wavelength λ1 of 920 nm and wavelengths at which the intensity is half the peak intensity of 915 nm and 925 nm. However, the spectral full width at half maximum of the peak of the promotion light L1 having the central wavelength λ1 is not limited to 10 nm and is preferably 5 nm or more and 1000 nm or less.

[0095] The condenser lens 321 is a convex lens corresponding to the condenser lens 12. However, the condenser lens 321 is disposed at a position where it collimates the promotion light L1 emitted by the light source 311, rather than where it collects the promotion light L1. In other words, the distance between the light source 311 and the condenser lens 321 is equal to the focal length of the condenser lens 321.

[0096] The light source 312 is a light source corresponding to the light source 21, and emits the inhibiting light L2. The light source 312 has the same configuration as the light source 21.

[0097] The condenser lens 322 is a convex lens corresponding to the condenser lens 22. However, the condenser lens 322 is disposed at a position where it collimates the inhibitory light L2 emitted by the light source 312, rather than where it collects the inhibitory light L2. In other words, the distance between the light source 312 and the condenser lens 322 is equal to the focal length of the condenser lens 322.

[0098] In addition, in Figure 6, a light beam corresponding to the light beam L11F (see Figure 1) represented by the chief ray L11 and a light beam corresponding to the light beam L21F (see Figure 2) represented by the chief ray L21 are shown, and other light beams are not shown.

[0099] The diffraction grating 33 is an example of a first spectrometer, and reflects incident light in different directions depending on the incident angle and wavelength. As shown in Fig. 6, the diffraction grating 33 reflects the promotion light L1 in different directions depending on the wavelength. In Fig. 6, promotion light L1A having a wavelength λ11 of 910 nm, promotion light L1B having a wavelength λ12 of 920 nm, and promotion light L1C having a wavelength λ13 of 930 nm are shown as representative examples of the promotion light L1. The diffraction grating 33 is designed so that all of the promotion light L1A, L1B, and L1C enter the effective area of ​​the focusing lens 34, and the direction of the reflecting surface is determined.

[0100] The diffraction grating 33 also reflects the inhibitory light L2 in a direction different from that of any of the promotion lights L1A, L1B, and L1C. The direction in which the diffraction grating 33 reflects the inhibitory light L2 can be selected by adjusting the angle of incidence of the inhibitory light L2 with respect to the incident surface of the diffraction grating 33. The angle of incidence of the inhibitory light L2 is determined so that the inhibitory light L2 enters the effective area of ​​the focusing lens 34.

[0101] The condenser lens 34 is a convex lens that converts the collimated promotion light beams L1A, L1B, and L1C and the inhibition light beam L2 into convergent light beams and condenses the light beams, and is an example of a first convex lens.

[0102] The LCOS 35 is an example of a spatial light modulator. Because a transmissive spatial light modulator is more suitable than a reflective spatial light modulator in the configuration of the optical shaping apparatus 3, a transmissive LCOS is used as an example of the spatial light modulator. However, a reflective spatial light modulator can also be used by interposing mirrors that reflect the promotion light L1A, L1B, and L1C and the inhibition light L2 toward the front or back of the page in FIG. 6 between the condenser lens 34 and the LCOS 35 and between the LCOS 35 and the condenser lens 36, and by installing a spatial light modulator that reflects the promotion light L1A, L1B, and L1C and the inhibition light L2 between these mirrors.

[0103] The LCOS 35 converts the intensity distributions of the promotion light beams L1A, L1B, and L1C, each of which is incident on a different region, into a pattern corresponding to the first region A1 (see, for example, FIGS. 3A and 3B). The LCOS 35 also converts the intensity distribution of the inhibition light beam L2, which is incident on a region different from any of the promotion light beams L1A, L1B, and L1C, into a pattern corresponding to the second region A2 (see, for example, FIGS. 3A and 3B). Similarly to the DMD 13 and DMD 23 included in the optical shaping apparatus 1, the LCOS 35 generates a pattern corresponding to the first region A1 and a pattern corresponding to the second region A2 in response to a control signal generated by the controller C (see FIG. 6).

[0104] The distance between the condenser lens 34 and the LCOS 35 is equal to the focal length f (unit: mm) of the condenser lens 34. Therefore, the LCOS 35 converts the promotion light beams L1A, L1B, and L1C and the inhibition light beam L2 incident as convergent light beams into divergent light beams.

[0105] The condenser lens 36 is a convex lens that converts the promotion light L1A, L1B, and L1C and the inhibition light L2, which are divergent light, into collimated light, and is an example of a second convex lens. The condenser lens 36 has the same configuration as the condenser lens 34. That is, the focal length of the condenser lens 36 is equal to the focal length f of the condenser lens 34. Therefore, the condenser lens 36 is disposed so that the distance between the LCOS 35 and the condenser lens 36 is the focal length f.

[0106] The diffraction grating 37 has the same configuration as the diffraction grating 33, and reflects incident light in different directions depending on the angle of incidence. The diffraction grating 37 is an example of a second spectrometer.

[0107] The diffraction grating 37 combines the promotion light beams L1A, L1B, and L1C and the inhibition light beam L2 that are separated by the diffraction grating 33 and enter the diffraction grating 37 from different directions. That is, the diffraction grating 37 combines the promotion light beams L1A, L1B, and L1C with the promotion light beam L1, and combines the promotion light beam L1 and the inhibition light beam L2.

[0108] The objective lens 38 is a convex lens corresponding to the objective lens 16 in the optical molding device 1, and focuses the promotion light L1 and the inhibition light L2 having the desired pattern by being spatially intensity modulated by the LCOS 35, and the promotion light L1 and the inhibition light L2 combined by the diffraction grating 37 onto the molding surface P.

[0109] In the optical shaping apparatus 3 configured in this manner, the distance between the diffraction grating 33 and the condenser lens 34, and the distance between the condenser lens 36 and the diffraction grating 37 are both equal to the focal length f of the condenser lens 34 and the condenser lens 36. The diffraction grating 33, the condenser lens 34, the LCOS 35, the condenser lens 36, and the diffraction grating 37 configured in this manner are an example of a 4f optical system in which the distance from the diffraction grating 33 to the diffraction grating 37 is 4f, and constitutes the irradiation unit of the optical shaping apparatus 3.

[0110] In the optical shaping device 3, the shaping surface P and the LCOS 35 are disposed at positions conjugate with the condenser lens 36 and the objective lens 38. In Fig. 6, the shaping surface P and the LCOS 35, which are at positions conjugate with the condenser lens 36 and the objective lens 38, are marked with black triangles.

[0111] In this embodiment, a diffraction grating is used as an example of the optical member constituting each of the first and second spectroscopes, but the optical members constituting the first and second spectroscopes are not limited to diffraction gratings and may be, for example, prisms.

[0112] <Summary of the photo-polymerization device> Similar to the photo-polymerization device 1, the photo-polymerization device 3 is a photo-polymerization device that forms a photo-polymerized object by irradiating a photo-curable resin containing a monomer, a polymerization initiator, and a polymerization inhibitor with promotion light L1 and inhibition light L2 having different wavelengths (using a two-wavelength photo-polymerization method).

[0113] The optical molding device 3 includes an area setting unit C1 (see (b) of FIG. 1) that sets a first area A1 to be irradiated with promotion light L1 and a second area A2 to be irradiated with inhibition light L2 on a molding surface P set inside the photocurable resin, and an irradiation unit that irradiates the first area A1 with promotion light L1, whose wavelength λ1 is n times (n is an integer of 2 or more) a first absorption wavelength included in the absorption band of the polymerization initiator, and irradiates the second area A2 with inhibition light L2, whose wavelength λ2 is a second absorption wavelength included in the absorption band of the polymerization inhibitor.

[0114] In the photopolymerization apparatus 3, as in the case of the photopolymerization apparatus 1, at least a portion of the second region A2 is in contact with or overlaps a portion of the first region A1, and the polymerization initiator is activated by absorbing n photons of the promotion light L1.

[0115] In the optical molding apparatus 3, the accelerating light L1 has a wavelength λ1 included in the absorption band of the polymerization initiator, and has a spectral full width at half maximum of 5 nm or more and 1000 nm or less.

[0116] In the optical molding device 3, the irradiation unit includes a lens (objective lens 38) that focuses the promotion light L1 and the inhibition light L2, a first spectrometer (diffraction grating 33), a first convex lens (condensing lens 34), a spatial light modulator (LCOS 35), a second convex lens (condensing lens 36), and a second spectrometer (diffraction grating 37) arranged to form a 4f optical system.

[0117] In the optical molding device 3, the spatial light modulator (LCOS 35) converts the intensity distribution of each of the promotion light L1 and the inhibition light L2 so that they have patterns corresponding to the first area A1 and the second area A2, respectively, and the molding surface P and the spatial light modulator (LCOS 35) are arranged in a conjugate position with respect to the lens (objective lens 38), and each of the promotion light L1 and the inhibition light L2 whose intensity distribution has been converted by the spatial light modulator (LCOS 35) is irradiated onto the first area A1 and the second area A2 on the molding surface P, respectively.

[0118] In addition, the manufacturing method for forming a photo-formed object using the photo-forming device 3 is a manufacturing method for a photo-formed object (using a two-wavelength photo-formed object method) in which a photo-curable resin containing a monomer, a polymerization initiator, and a polymerization inhibitor is irradiated with promoting light and inhibiting light having different wavelengths to form a photo-formed object.

[0119] This manufacturing method includes an area setting step of setting a first area A1 to be irradiated with promotion light L1 and a second area A2 to be irradiated with inhibition light L2 on a molding surface P set inside the photocurable resin, and an irradiation step of irradiating the first area A1 with promotion light L1 whose wavelength λ1 is n times (n is an integer of 2 or more) a first absorption wavelength included in the absorption band of the polymerization initiator, and irradiating the second area A2 with inhibition light L2 whose wavelength λ2 is a second absorption wavelength included in the absorption band of the polymerization inhibitor.

[0120] In this manufacturing method, at least a portion of the second region A2 is in contact with or overlaps a portion of the first region A1, and in the irradiation process, the polymerization initiator is activated by absorbing n photons of the promotion light.

[0121] In the present production method, the accelerating light L1 has a wavelength λ1 included in the absorption band of the polymerization initiator and a spectral full width at half maximum of 5 nm to 1000 nm.

[0122] Furthermore, in the irradiation process, an irradiation unit is used in which a first spectrometer (diffraction grating 33), a first convex lens (condensing lens 34), a spatial light modulator (LCOS 35), a second convex lens (condensing lens 36), and a second spectrometer (diffraction grating 37) are arranged to form a 4f optical system, and the intensity distribution of each of the promotion light L1 and the inhibition light L2 is converted using the spatial light modulator (LCOS 35) so that it has a pattern corresponding to each of the first area A1 and the second area A2, and is irradiated onto each of the first area A1 and the second area A2 on the forming surface P.

[0123] [Embodiment 4] A photo-lithography apparatus according to embodiment 4 of the present invention will be described with reference to Figs. 7 and 8. Fig. 7(a) is a plan view showing the irradiation pattern of the promotion light L1 and the inhibition light L2 imaged on the shaping surface P of the photo-lithography apparatus. Fig. 7(b) is a graph showing the intensity distribution of the promotion light L1 and the inhibition light L2 shown in Fig. 7(a). Fig. 8 is a graph in which the oxygen concentration distribution and the oxygen flow rate distribution are added to the graph shown in Fig. 7(b).

[0124] This optical shaping device has the same configuration as the optical shaping device 1 according to the first embodiment, but the shape of the first area A1 set by the area setting unit C1 is different from that of the optical shaping device 1. In this embodiment, a description of the configuration of this optical shaping device that is common to the optical shaping device 1 will be omitted, and the first area A1 used in this optical shaping device will be mainly described.

[0125] In this embodiment, the irradiation pattern of the acceleration light L1 is shown in Fig. 7 as an example. As shown in Figs. 7(a) and 7(b), the DMD 13 irradiates the first region A1 of the printing surface P with acceleration light L1 whose time-average intensity is higher than the printing threshold Th, and irradiates the third region A3 of the printing surface P with acceleration light L1 whose time-average intensity is lower than the printing threshold Th. The DMD 13, together with the tube lens 14 and the objective lens 16 (described later), constitutes an irradiation unit. In this embodiment, the acceleration light L1 to be irradiated onto each of the first region A1 and the third region A3 is generated using light emitted from the light source 11.

[0126] In the irradiation pattern shown in (a) of Figure 7, the first region A1 is a region in which the outer edge A11 is a square, and the third region A3 is a region in which the outer edge A31 and the inner edge A32 are both square. As can be seen from (a) and (b) of Figure 7, in this irradiation pattern, the outer edge A31 surrounds the outer edge A11. Furthermore, in this irradiation pattern, the inner edge A32 surrounds the outer edge A11 while being in contact with the outer edge A11.

[0127] In this embodiment, the diffusion coefficient of oxygen in the photocurable resin R is defined as D [cm ２ s －１ ], and the consumption rate of the oxygen concentration in the photocurable resin R when irradiated with the acceleration light L1 is ν [s－１ ], and the distance L between the outer edge A11 of the first region A1 and the outer edge A31 of the third region A3 on the printing surface P is 4(D / ν) １／２ The third area A3 is designed so that D=1×10 －８ cm ２ s －１ , and ν=4×10 －３ s －１ Assuming this, L=64 μm.

[0128] The coefficient 4 defining the distance L is determined by ln(2 / 100) assuming that the oxygen concentration n at the outer edge A11 is 2% of the oxygen concentration n0, where n0 is the oxygen concentration when the accelerating light L1 is not irradiated. This coefficient can be determined appropriately based on the ratio of the oxygen concentration n to the desired oxygen concentration n0. The ratio of the oxygen concentration n to the desired oxygen concentration n0 can also be determined based on the size of the object to be optically shaped. The size of an object with an irregular shape in plan view can be defined as the square root of the area obtained when the object is viewed in plan. The size of an object with a rectangular shape in plan view may also be defined by the length of its short side. The size of an object with a circular shape in plan view may also be defined by the length of its diameter.

[0129] In the irradiation pattern used by the optical shaping apparatus 1 of this embodiment, the third region A3 is disposed so that its outer edge A31 surrounds the outer edge A11 of the first region A1. Furthermore, the third region A3 is irradiated with the acceleration light L1, the time-averaged intensity of which is lower than the shaping threshold value, thereby consuming oxygen in the third region A3. Therefore, the diffusion of oxygen from the third region A3 to the first region A1 can be suppressed (more preferably, prevented).

[0130] As in this irradiation pattern, the third region A3 preferably has a closed annular shape in plan view, and preferably surrounds the first region A1 without a break. The closed annular shape of the third region A3 can suppress (more preferably prevent) the diffusion of oxygen from outside the third region A3 to the first region A1 without passing through the third region A3.

[0131] In this irradiation pattern, oxygen may diffuse from outside the third region A3 into the third region A3 near the outer edge A31 of the third region A3 (see the oxygen flux in FIG. 8 ). However, by making the distance L longer than the diffusion length of oxygen, the amount of oxygen that can reach the outer edge A11 of the first region A1 from the third region A3 can be significantly reduced (see the oxygen concentration in FIG. 8 ).

[0132] In this way, the photopolymerization apparatus of this embodiment can reduce the inhibition of the polymerization reaction by oxygen, thereby making it possible to suppress more than ever before the discrepancy that may occur between the planar shape of the area irradiated with the first light and the planar shape of the area where the photocurable resin has hardened.

[0133] [Example of implementation by software] The functions of the optical prototyping apparatus 1 according to embodiment 1, the optical prototyping apparatus 3 according to embodiment 3, and the optical prototyping apparatus according to embodiment 4 (hereinafter referred to as "apparatus") can be realized by a program that causes a computer to function as the apparatus, and a program that causes a computer to function as each control block of the apparatus (particularly each part included in the control unit C).

[0134] In this case, the device includes a computer having at least one control device (e.g., a processor) and at least one storage device (e.g., a memory) as hardware for executing the program. The functions described in each of the above embodiments are realized by executing the program using the control device and storage device.

[0135] The program may be non-transitory and may be recorded on one or more computer-readable recording media. The recording media may or may not be included in the device. In the latter case, the program may be supplied to the device via any wired or wireless transmission medium.

[0136] Furthermore, some or all of the functions of the control blocks can be realized by logic circuits. For example, an integrated circuit in which a logic circuit that functions as each of the control blocks is formed is also included in the scope of the present invention. In addition, the functions of the control blocks can also be realized by, for example, a quantum computer.

[0137] The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims. Embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the present invention.

[0138] 〔summary〕 In order to enhance the resolution at least in the propagation direction of the acceleration light in a liquid-phase polymerization-based stereolithography technique, a method for producing a stereolithography object according to a first aspect of the present invention (using a dual-wavelength stereolithography method) is provided, in which a photocurable resin containing a monomer, a polymerization initiator, and a polymerization inhibitor is irradiated with acceleration light and inhibitory light having different wavelengths to form a stereolithography object. The method includes a region setting step of setting a first region to be irradiated with the acceleration light and a second region to be irradiated with the inhibitory light on a modeling surface set within the photocurable resin, and an irradiation step of irradiating the first region with acceleration light having a wavelength λ1 that is n times (n is an integer of 2 or greater) a first absorption wavelength that is included in the absorption band of the polymerization initiator, and irradiating the second region with inhibitory light having a wavelength λ2 that is a second absorption wavelength that is included in the absorption band of the polymerization inhibitor, wherein at least a portion of the second region is in contact with or overlaps with a portion of the first region, and in the irradiation step, the polymerization initiator is activated by absorbing n photons of the acceleration light.

[0139] According to the above configuration, in addition to the dual-wavelength stereolithography method in which an accelerating light beam and an inhibiting light beam are used to form a stereolithography object, a multiphoton absorption method is used in which a polymerization initiator is irradiated with an accelerating light beam having a wavelength n times the first absorption wavelength, and the polymerization initiator is activated by absorbing n photons of the accelerating light beam. Therefore, even when a two-dimensional stereolithography object is formed without changing the position of the modeling surface inside the photocurable resin, the resolution in the propagation direction of the accelerating light can be improved.

[0140] Furthermore, when forming a three-dimensional photo-fabricated object using the Layer-by-Layer method, the polymerization initiator is activated only on the modeling surface or in the immediate vicinity of the modeling surface within the photo-curable resin, and the polymerization reaction proceeds. Because the photo-fabricated object is formed only on the modeling surface or in the immediate vicinity of the modeling surface within the photo-curable resin, it is possible to suppress unexpected curing of the photo-curable resin that may occur in areas behind the focus. As a result, when forming a three-dimensional photo-fabricated object, it is possible to increase not only the resolution in the propagation direction of the accelerating light but also the resolution in the in-plane direction of the modeling surface.

[0141] As described above, the present method for producing a stereolithographic object can improve the resolution at least in the propagation direction of the accelerating light in a stereolithography technique using liquid phase polymerization.

[0142] Furthermore, in the method for manufacturing a photo-fabricated object according to the second aspect of the present invention, in addition to the configuration of the method for manufacturing a photo-fabricated object according to the first aspect described above, a configuration is adopted in which, in the irradiation step, the intensity distribution of the inhibitory light is converted using a spatial light modulator so that it has a pattern corresponding to the second region, and the inhibitory light is irradiated onto the second region on the modeling surface.

[0143] According to the above configuration, since the inhibitory light can be irradiated onto the second region using the spatial light modulator, for example, by using the inhibitory light in combination with the accelerating light, which covers the entire modeling surface as the first region, it is possible to form a stereolithographic object having a desired shape without using a scanning mechanism such as a galvano scanner. Therefore, the time required for stereolithography can be shortened compared to when a scanning mechanism such as a galvano scanner is used.

[0144] Furthermore, in the method for manufacturing a photo-fabricated object according to the third aspect of the present invention, in addition to the configuration of the method for manufacturing a photo-fabricated object according to the second aspect described above, in the irradiation step, the intensity distribution of the promotion light is converted using a spatial light modulator other than the spatial light modulator so that it has a pattern corresponding to the first region, and the promotion light is irradiated onto the first region on the modeling surface.

[0145] According to the above configuration, a pattern of the accelerating light as well as the inhibiting light can be formed using the spatial light modulator. Therefore, compared to the method for manufacturing a stereolithographic object according to the second aspect of the present invention, the area of ​​the second region overlapping the first region can be made smaller, thereby reducing unnecessary consumption of the polymerization initiator.

[0146] Furthermore, in a fourth aspect of the present invention, in addition to the configuration of the method for manufacturing a photo-fabricated object according to the first aspect described above, a configuration is adopted in which the promotion light has a wavelength λ1 included in the absorption band of the polymerization initiator and has a spectral full width at half maximum of 5 nm or more and 1000 nm or less, the irradiation step uses an irradiation unit arranged so that a first spectrometer, a first convex lens, a spatial light modulator, a second convex lens, and a second spectrometer form a 4f optical system, and the intensity distribution of each of the promotion light and the inhibitory light is converted by the spatial light modulator so as to have a pattern corresponding to each of the first region and the second region, and the promotion light and the inhibitory light are irradiated onto each of the first region and the second region on the modeling surface.

[0147] When the promotion light is patterned using a spatial light modulator, the power density at each position included in the first region is more likely to decrease than when the promotion light is focused at one point.

[0148] According to the above configuration, (1) the first spectrometer separates the acceleration light having a wide spectral full width at half maximum into wavelengths, thereby separating the optical paths of the respective acceleration light beams, (2) the spatial light modulator converts the separated acceleration light beams into acceleration light beams having a pattern corresponding to the first region, and (3) the second spectrometer aligns the optical paths of the acceleration light beams having the pattern corresponding to the first region. Therefore, compared with the case where monochromatic acceleration light is used, the intensity of the acceleration light beam can be easily increased, and therefore the photocurable resin contained in the first region can be reliably cured even when the spatial light modulator is used.

[0149] Furthermore, in a fifth aspect of the present invention, in addition to the configuration of the method for manufacturing a photo-fabricated object according to any one of the first to fourth aspects described above, the method further includes an intensity setting step performed between the region setting step and the irradiation step, in which the region setting step further sets a first degree of polymerization that is a target degree of polymerization in the first region and a second degree of polymerization that is a target degree of polymerization in the second region, and the intensity setting step sets an intensity distribution of the promotion light in the first region and an intensity distribution of the inhibition light in the second region so that the estimated degree of polymerization in the first region is equal to or greater than the first degree of polymerization and the estimated degree of polymerization in the second region is less than the second degree of polymerization.

[0150] According to the above configuration, the photocurable resin contained in the first region can be cured while the photocurable resin contained in the second region can be prevented from being cured, so that even when two-photon absorption and multi-photon absorption methods are used in combination, a photo-molded object having a desired shape can be formed within the molding surface.

[0151] Furthermore, in the method for manufacturing an optically shaped object according to a sixth aspect of the present invention, in addition to the configuration of the method for manufacturing an optically shaped object according to the fifth aspect described above, the intensity setting step refers to a correlation between an acceleration light intensity, which is the irradiation intensity of the acceleration light, an inhibition light intensity, which is the irradiation intensity of the inhibition light, and an estimated degree of polymerization estimated from the acceleration light intensity and the inhibition light intensity, and sets the intensity distribution of each of the acceleration light and the inhibition light.

[0152] According to the above configuration, even when two-photon absorption and multi-photon absorption are used in combination, a photo-fabricated object having a desired shape can be reliably formed within the fabrication surface.

[0153] Furthermore, in a seventh aspect of the present invention, in addition to the configuration of the method for manufacturing a photo-fabricated object according to any one of the first to sixth aspects described above, a configuration is adopted in which the area setting step further sets a third area on the modeling surface to be irradiated with oxygen-consuming light, the irradiation step irradiates the first area and the second area with the promoting light and the inhibiting light, respectively, and irradiates the third area with the oxygen-consuming light, the wavelength of which is m times (m is an integer of 1 or more) a third absorption wavelength included in the absorption band of the polymerization initiator, and the outer edge of the third area on the modeling surface surrounds the outer edge of the first area.

[0154] The inventors of the present application have discovered that oxygen contained in a liquid photocurable resin can inhibit the polymerization reaction of the photocurable resin.

[0155] According to the above configuration, since the oxygen-consuming light is irradiated onto the third region, it is possible to reduce oxygen diffusing from outside the outer edge of the first region into the first region, thereby reducing the inhibition of the polymerization reaction caused by oxygen, and thus it is possible to more effectively prevent a discrepancy between the planar shape of the region irradiated with the first light and the planar shape of the region where the photocurable resin is cured.

[0156] In order to improve the resolution at least in the propagation direction of the acceleration light in a liquid-phase polymerization-based stereolithography technique, the stereolithography apparatus according to an eighth aspect of the present invention is an optical lithography apparatus (using a dual-wavelength stereolithography method) that forms a stereolithography object by irradiating a photocurable resin containing a monomer, a polymerization initiator, and a polymerization inhibitor with acceleration light and inhibitory light having different wavelengths, and includes: an area setting unit that sets a first area to be irradiated with the acceleration light and a second area to be irradiated with the inhibitory light on a modeling surface set inside the photocurable resin; and an irradiation unit that irradiates the first area with acceleration light whose wavelength λ1 is n times (n is an integer of 2 or more) the absorption wavelength included in the absorption band of the polymerization initiator, and irradiates the second area with inhibitory light whose wavelength λ2 is an absorption wavelength included in the absorption band of the polymerization inhibitor, wherein at least a portion of the second area is in contact with or overlaps with a portion of the first area, and the polymerization initiator is activated by absorbing n photons of the acceleration light.

[0157] In addition, in a photo-polymerization apparatus according to a ninth aspect of the present invention, in addition to the configuration of the photo-polymerization apparatus according to the eighth aspect described above, the irradiation unit includes a lens that focuses the promotion light and the inhibition light, and a spatial light modulator that converts the intensity distribution of the inhibition light to have a pattern corresponding to the second region, the modeling surface and the spatial light modulator are arranged in a conjugate position with respect to the lens, and the inhibition light whose intensity distribution has been converted by the spatial light modulator is irradiated onto the second region on the modeling surface.

[0158] Furthermore, in a tenth aspect of the optical shaping apparatus of the present invention, in addition to the configuration of the optical shaping apparatus of the ninth aspect described above, the irradiation unit further includes a spatial light modulator separate from the spatial light modulator that converts the intensity distribution of the promotion light to have a pattern corresponding to the first region, the shaping surface and the separate spatial light modulator are arranged in a conjugate position with respect to the lens, and the promotion light whose intensity distribution has been converted by the separate spatial light modulator is irradiated onto the first region on the shaping surface.

[0159] In addition to the configuration of the optical shaping apparatus according to the eighth aspect, an optical shaping apparatus according to an eleventh aspect of the present invention has the following configuration: the acceleration light has a wavelength λ1 included in the absorption band of the polymerization initiator and has a spectral full width at half maximum of 5 nm to 1000 nm; the irradiation unit includes a lens that focuses the acceleration light and the inhibitory light, and a first spectrometer, a first convex lens, a spatial light modulator, a second convex lens, and a second spectrometer arranged to form a 4f optical system; the spatial light modulator converts the intensity distribution of each of the acceleration light and the inhibitory light so that they have patterns corresponding to the first region and the second region, respectively; the modeling surface and the spatial light modulator are arranged at conjugate positions with respect to the lens; and the acceleration light and the inhibitory light, whose intensity distributions have been converted by the spatial light modulator, are irradiated onto the first region and the second region on the modeling surface, respectively.

[0160] Furthermore, a photo-polymerization apparatus according to a twelfth aspect of the present invention includes the same configuration as the photo-polymerization apparatus according to any one of the eighth to eleventh aspects described above, and further includes an intensity setting unit, wherein the region setting unit further sets a first degree of polymerization that is a target degree of polymerization in the first region and a second degree of polymerization that is a target degree of polymerization in the second region, and the intensity setting unit sets the intensity distribution of the promotion light in the first region and the intensity distribution of the inhibition light in the second region so that the estimated degree of polymerization in the first region is equal to or greater than the first degree of polymerization and the estimated degree of polymerization in the second region is less than the second degree of polymerization.

[0161] Furthermore, in the optical shaping apparatus according to the thirteenth aspect of the present invention, in addition to the configuration of the optical shaping apparatus according to the twelfth aspect described above, a configuration is adopted in which the intensity setting unit sets the intensity distribution of each of the acceleration light and the inhibition light by referring to the correlation between the acceleration light intensity, which is the irradiation intensity of the acceleration light, the inhibition light intensity, which is the irradiation intensity of the inhibition light, and an estimated degree of polymerization estimated from the acceleration light intensity and the inhibition light intensity.

[0162] Furthermore, in a photo-polymerization apparatus according to a fourteenth aspect of the present invention, in addition to the configuration of the photo-polymerization apparatus according to any one of the eighth to thirteenth aspects described above, the area setting unit further sets a third area on the modeling surface to be irradiated with oxygen-consuming light, the irradiation unit irradiates the first area and the second area with the promoting light and the inhibiting light, respectively, and irradiates the third area with the oxygen-consuming light whose wavelength is m times (m is an integer of 1 or more) a third absorption wavelength included in the absorption band of the polymerization initiator, and the outer edge of the third area on the modeling surface surrounds the outer edge of the first area.

[0163] The photopolymerization apparatus according to each of the eighth to fourteenth aspects of the present invention corresponds to the method for manufacturing a photopolymerized object according to each of the first to seventh aspects of the present invention, and therefore achieves the same effects as the method for manufacturing a photopolymerized object according to each of the first to seventh aspects of the present invention.

[0164] 1, 3 Optical shaping device 11, 21, 311, 312 Light source 12, 22, 321, 322 Condenser lens 13, 23 DMD 14 Tube lens 15, 24 Mirror 16, 38 Objective lens 25 Dichroic mirror 111, 211 Light-emitting area 34, 36 Condenser lens 35 LCOS 33, 37 Diffraction grating A1 First area A11, A21, A31 Outer edge A2 Second area A22, A32 Inner edge A3 Third area L1, L1A, L1B, L1C Promotion light L11, L12, L13, L21, L22, L23 Chief light ray L11F, L21F Light beam L2 Inhibition light

Claims

1. A method for manufacturing a photo-fabricated object, in which a photo-curable resin containing a monomer, a polymerization initiator, and a polymerization inhibitor is irradiated with accelerating light and inhibiting light having different wavelengths to form a photo-fabricated object, the method comprising: a region setting step of setting a first region to be irradiated with the accelerating light and a second region to be irradiated with the inhibiting light on a modeling surface set inside the photo-curable resin; and an irradiation step of irradiating the first region with accelerating light whose wavelength λ1 is n times (n is an integer of 2 or more) a first absorption wavelength included in the absorption band of the polymerization initiator, and irradiating the second region with inhibiting light whose wavelength λ2 is a second absorption wavelength included in the absorption band of the polymerization inhibitor, wherein at least a portion of the second region is in contact with or overlaps with a portion of the first region, and wherein in the irradiation step, the polymerization initiator is activated by absorbing n photons of the accelerating light.

2. The method for manufacturing a photo-fabricated object according to claim 1, wherein in the irradiation step, the intensity distribution of the inhibitory light is converted using a spatial light modulator so as to have a pattern corresponding to the second region, and the inhibitory light is irradiated onto the second region on the modeling surface.

3. The method for manufacturing a photo-formed object according to claim 2, wherein in the irradiation step, the intensity distribution of the promotion light is converted using a spatial light modulator other than the spatial light modulator so that the promotion light has a pattern corresponding to the first area, and the promotion light is irradiated onto the first area on the modeling surface.

4. The method for producing a photo-formed object according to claim 1, wherein the promotion light has a wavelength λ1 included in the absorption band of the polymerization initiator and a spectral full width at half maximum of 5 nm or more and 1000 nm or less, and in the irradiation step, an irradiation unit is used in which a first spectrometer, a first convex lens, a spatial light modulator, a second convex lens, and a second spectrometer are arranged to form a 4f optical system, and the intensity distribution of each of the promotion light and the inhibitory light is converted using the spatial light modulator so that it has a pattern corresponding to each of the first region and the second region, and the first region and the second region on the modeling surface are irradiated with the light.

5. The method for manufacturing a photo-fabricated object according to any one of claims 1 to 4, further comprising an intensity setting step performed between the region setting step and the irradiation step, wherein the region setting step further sets a first degree of polymerization that is a target degree of polymerization in the first region and a second degree of polymerization that is a target degree of polymerization in the second region, and the intensity setting step sets the intensity distribution of the accelerating light in the first region and the intensity distribution of the inhibiting light in the second region so that the estimated degree of polymerization in the first region is equal to or greater than the first degree of polymerization and the estimated degree of polymerization in the second region is less than the second degree of polymerization.

6. The method for manufacturing a photo-fabricated object according to claim 5, wherein the intensity setting process sets the intensity distribution of each of the promotion light and the inhibitory light by referring to a correlation between an promotion light intensity, which is the irradiation intensity of the promotion light, an inhibitory light intensity, which is the irradiation intensity of the inhibitory light, and an estimated degree of polymerization estimated from the promotion light intensity and the inhibitory light intensity.

7. The method for manufacturing a photo-fabricated object according to any one of claims 1 to 6, wherein the region setting step further sets a third region on the modeling surface onto which oxygen-consuming light is irradiated, and the irradiation step irradiates the first region and the second region with the accelerating light and the inhibiting light, respectively, and irradiates the third region with the oxygen-consuming light, the wavelength of which is m times (m is an integer of 1 or more) a third absorption wavelength included in the absorption band of the polymerization initiator, and the outer edge of the third region on the modeling surface surrounds the outer edge of the first region.

8. A photo-fabrication device that forms a photo-fabricated object by irradiating a photo-curable resin containing a monomer, a polymerization initiator, and a polymerization inhibitor with accelerating light and inhibiting light having different wavelengths, the device comprising: a region setting unit that sets a first region to be irradiated with the accelerating light and a second region to be irradiated with the inhibiting light on a modeling surface set inside the photo-curable resin; and an irradiation unit that irradiates the first region with accelerating light whose wavelength λ1 is n times (n is an integer of 2 or more) a first absorption wavelength included in the absorption band of the polymerization initiator, and irradiates the second region with inhibiting light whose wavelength λ2 is a second absorption wavelength included in the absorption band of the polymerization inhibitor; at least a portion of the second region is in contact with or overlaps with a portion of the first region; and the polymerization initiator is activated by absorbing n photons of the accelerating light.

9. The optical shaping device described in claim 8, wherein the irradiation unit comprises a lens that focuses the promotion light and the inhibition light, and a spatial light modulator that converts the intensity distribution of the inhibition light to have a pattern corresponding to the second region, the modeling surface and the spatial light modulator are arranged in a conjugate position with respect to the lens, and the inhibition light whose intensity distribution has been converted by the spatial light modulator is irradiated onto the second region on the modeling surface.

10. The optical shaping device of claim 9, wherein the irradiation unit further comprises a spatial light modulator separate from the spatial light modulator that converts the intensity distribution of the promotion light to have a pattern corresponding to the first region, the modeling surface and the separate spatial light modulator are positioned conjugate with respect to the lens, and the promotion light whose intensity distribution has been converted by the separate spatial light modulator is irradiated onto the first region on the modeling surface.

11. The optical shaping device of claim 8, wherein the acceleration light has a wavelength λ1 included in the absorption band of the polymerization initiator and a spectral full width at half maximum of 5 nm or more and 1000 nm or less, the irradiation unit comprises a lens that focuses the acceleration light and the inhibitory light, and a first spectrometer, a first convex lens, a spatial light modulator, a second convex lens, and a second spectrometer arranged to form a 4f optical system, the spatial light modulator converts the intensity distribution of each of the acceleration light and the inhibitory light so that they have patterns corresponding to the first region and the second region, respectively, the modeling surface and the spatial light modulator are arranged in a conjugate position with respect to the lens, and the acceleration light and the inhibitory light, whose intensity distribution has been converted by the spatial light modulator, are irradiated onto the first region and the second region on the modeling surface, respectively.

12. An optical shaping device according to any one of claims 8 to 11, further comprising an intensity setting unit, wherein the region setting unit further sets a first degree of polymerization that is a target degree of polymerization in the first region and a second degree of polymerization that is a target degree of polymerization in the second region, and the intensity setting unit sets the intensity distribution of the promotion light in the first region and the intensity distribution of the inhibition light in the second region so that the estimated degree of polymerization in the first region is equal to or greater than the first degree of polymerization and the estimated degree of polymerization in the second region is less than the second degree of polymerization.

13. The optical shaping device according to claim 12, wherein the intensity setting unit sets the intensity distribution of each of the acceleration light and the inhibitory light by referring to a correlation between an acceleration light intensity, which is the irradiation intensity of the acceleration light, an inhibitory light intensity, which is the irradiation intensity of the inhibitory light, and an estimated degree of polymerization estimated from the acceleration light intensity and the inhibitory light intensity.

14. The optical shaping device according to any one of claims 8 to 13, wherein the area setting unit further sets a third area on the modeling surface onto which oxygen-consuming light is irradiated, the irradiation unit irradiates the first area and the second area with the accelerating light and the inhibiting light, respectively, and irradiates the third area with the oxygen-consuming light having a wavelength m times (m is an integer of 1 or more) a third absorption wavelength included in the absorption band of the polymerization initiator, and the outer edge of the third area on the modeling surface surrounds the outer edge of the first area.

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