JP2009132125A - Optical shaping apparatus and optical shaping method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical shaping apparatus which can shape a precision shaped article, and to provide an optical shaping method. <P>SOLUTION: In accordance with a small work domain obtained by partitioning a whole work domain wherein optical shaping work is carried out into a plurality of domains, the cross section shape data of a three-dimensional model are partitioned to produce small work domain data which are cross section shape data corresponding to the small work domain. An exposure turn to expose the small work domain according to the small work domain data is determined so that after a prescribed small work domain is exposed, the small work domain which is separated by at least one small work domain from the prescribed small work domain is exposed. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an optical modeling apparatus and an optical modeling method, and more particularly, to an optical modeling apparatus and an optical modeling method that can model a highly accurate modeled object.

  Conventionally, when creating a three-dimensional model (modeled object) using three-dimensional shape data created by CAD (Computer Aided Design), for example, a numerically controlled machining machine or the like is used. Is created.

  In recent years, a technique called rapid prototyping (RP: Rapid Prototyping) for creating a three-dimensional model without machining has attracted attention in many manufacturing sites. Rapid prototyping is called additive manufacturing, in which a thin plate with a cross-sectional shape obtained by slicing a three-dimensional model is created based on the three-dimensional shape data of the three-dimensional model, and a three-dimensional model is created by stacking the thin plates with the cross-sectional shape. Manufacturing techniques are used.

  Rapid prototyping is based on the method of creating a thin plate having a cross-sectional shape, such as stereolithography using an ultraviolet curable resin, extrusion lamination of thermoplastic resin (FDM), powder melt adhesion lamination (SLS), paper Are classified into a thin film stacking method (LOM), a method of discharging powder and a curing catalyst and laminating (Ink-Jet method).

  For example, in stereolithography, 3D shape data of a stereo model created by CAD is converted into STL (Stereo Lithography), which is a format in which the surface of the stereo model is represented by a small triangular surface, and the stereolithography device Is input.

  The stereolithography apparatus creates cross-sectional shape data obtained by slicing a three-dimensional model from the three-dimensional shape data, for example, at regular intervals of about 0.1 to 0.2 mm, and the surface of the liquid photo-curing resin according to the cross-sectional shape data. The irradiation area of the light to be irradiated is determined. The stereolithography apparatus irradiates the surface of the liquid photocurable resin with light of the irradiation region corresponding to the cross sectional shape data for each layer of the cross sectional shape data, and a moving gantry in the liquid photocurable resin. The three-dimensional model is moved vertically downward according to the sliced thickness. Then, the stereolithography apparatus generates a three-dimensional model by repeating the light irradiation and the movement of the movable frame from the lowermost layer to the uppermost layer of the cross-sectional shape data.

  Here, Patent Document 1 discloses an image recording apparatus that uses a spatial light modulator, modulates ultraviolet rays according to image data, and records an image on a photosensitive resin with the ultraviolet rays.

JP-A-6-95257

  Although the optical modeling apparatus is configured as described above, an apparatus capable of modeling a model with higher accuracy than the conventional optical modeling apparatus has been demanded.

  This invention is made | formed in view of such a condition, and enables it to model a highly accurate molded article.

  The stereolithography apparatus according to one aspect of the present invention irradiates the surface of a photocurable resin with light according to cross-sectional shape data of a three-dimensional model to form a hardened layer, and stacks the hardened layer to form the three-dimensional model. It is an optical modeling apparatus for modeling, and the cross-sectional shape data of the three-dimensional model is divided according to the work small area obtained by dividing the entire work area where the optical modeling work is performed into a plurality of areas, and corresponds to the work small area Data generating means for generating work small area data, which is cross-sectional shape data, and an exposure order in which the work small areas are exposed in accordance with the work small area data, after the predetermined work small areas are exposed Determining means for determining that at least one work sub-region away from the predetermined work sub-region is exposed.

  The stereolithography method according to one aspect of the present invention is directed to irradiating the surface of a photocurable resin with light according to cross-sectional shape data of a three-dimensional model to form a hardened layer, and laminating the hardened layer to form the solid model. An optical modeling method for modeling, wherein the cross-sectional shape data of the three-dimensional model is divided according to a work small area obtained by dividing an entire work area where the optical modeling work is performed into a plurality of areas, and corresponds to the work small area Workpiece small region data that is cross-sectional shape data is generated, the exposure order in which the workpiece small regions are exposed in accordance with the workpiece small region data is set, and then the predetermined workpiece small regions are exposed, Determining at least one work sub-region away from the work sub-region to be exposed.

  In one aspect of the present invention, the cross-sectional shape data of the three-dimensional model is divided according to a work small area obtained by dividing the entire work area where the optical modeling operation is performed into a plurality of areas, and the cross-sectional shape corresponding to the work small area Work small area data which is data is generated. Then, the exposure order in which the work small areas are exposed according to the work small area data is such that, after the predetermined work small areas are exposed, at least one work small area that is separated from the predetermined work small areas is exposed. To be determined.

  According to one aspect of the present invention, a highly accurate model can be modeled.

  Embodiments of the present invention will be described below. Correspondences between the constituent elements of the present invention and the embodiments described in the specification or the drawings are exemplified as follows. This description is intended to confirm that the embodiments supporting the present invention are described in the specification or the drawings. Therefore, even if there is an embodiment which is described in the specification or the drawings but is not described here as an embodiment corresponding to the constituent elements of the present invention, that is not the case. It does not mean that the form does not correspond to the constituent requirements. Conversely, even if an embodiment is described herein as corresponding to a configuration requirement, that means that the embodiment does not correspond to a configuration requirement other than the configuration requirement. It's not something to do.

The stereolithography apparatus according to one aspect of the present invention irradiates the surface of a photocurable resin with light according to cross-sectional shape data of a three-dimensional model to form a hardened layer, and stacks the hardened layer to form the three-dimensional model. An optical modeling apparatus for modeling,
The workpiece small area which is the sectional shape data corresponding to the workpiece small area by dividing the sectional shape data of the three-dimensional model according to the workpiece small area obtained by dividing the entire workpiece area where the optical modeling work is performed into a plurality of areas. Data generation means for generating data (for example, the control unit 21 in FIG. 1 that executes the process of step S13 in FIG. 5);
An exposure order in which the work small areas are exposed in accordance with the work small area data is set such that at least one work small area is separated from the predetermined work small areas after the predetermined work small areas are exposed. Determining means (for example, the control unit 21 in FIG. 1 that executes the process of step S14 in FIG. 5).

Moreover, the optical modeling apparatus of one aspect of the present invention is
Collective exposure means (for example, the spatial light modulator 17 in FIG. 1) that collectively exposes the surface of the photocurable resin based on the work small area data generated by the data generation means to form the cured layer. When,
In accordance with the order of exposure determined by the determining means, one of the collective exposure means and the cured layer is placed in the direction perpendicular to the optical axis of the light irradiated from the collective exposure means to the photocurable resin. And a moving means (for example, the stage 33 in FIG. 1) that moves relative to each other.

The stereolithography method according to one aspect of the present invention is directed to irradiating the surface of a photocurable resin with light according to cross-sectional shape data of a three-dimensional model to form a hardened layer, and stacking the hardened layer to form the three-dimensional model. An optical modeling method for modeling,
The workpiece small area which is the sectional shape data corresponding to the workpiece small area by dividing the sectional shape data of the three-dimensional model according to the workpiece small area obtained by dividing the entire workpiece area where the optical modeling work is performed into a plurality of areas. Data is generated (for example, step S13 in FIG. 5);
An exposure order in which the work small areas are exposed in accordance with the work small area data is set such that at least one work small area is separated from the predetermined work small areas after the predetermined work small areas are exposed. Is determined to be exposed (for example, step S14 in FIG. 5).
Includes steps.

  Hereinafter, specific embodiments to which the present invention is applied will be described in detail with reference to the drawings.

  FIG. 1 is a block diagram showing a configuration example of an embodiment of an optical modeling apparatus to which the present invention is applied.

  In FIG. 1, the optical modeling apparatus 11 includes a light source 12, a shutter 13, a polarizing plate 14, a beam integrator 15, a mirror 16, a spatial light modulator 17, a condenser lens 18, an objective lens 19, a work unit 20, and a control unit 21. Consists of

  As the light source 12, for example, a high-power blue LED arranged in an array can be used. The light source 12 exposes the ultraviolet curable resin 31 of the work unit 20 to form a cured layer. Radiate. As the light source 12, it is not necessary to use a coherent laser light source.

  The shutter 13 passes or blocks the light emitted from the light source 12 under the control of the control unit 21, and controls on / off of the exposure of the ultraviolet curable resin 31 by the light from the light source 12.

  The polarizing plate 14 sets light that has passed through the shutter 13 as predetermined polarized light. In other words, the polarizing plate 14 polarizes the light so that the spatial light modulator 17 composed of a transmissive liquid crystal panel can spatially modulate the light from the light source 12.

  The beam integrator 15 makes the light polarized by the polarizing plate 14 uniform. As the beam integrator 15, a general type such as a fly-eye type in which a plurality of lens elements are arranged, or a light rod type in which the inside of a columnar rod lens such as a square column is totally reflected is used.

  The mirror 16 reflects the light uniformed by the beam integrator 15 toward the spatial light modulator 17.

  The spatial light modulator 17 is formed of, for example, a transmissive liquid crystal panel, and the light reflected by the mirror 16 exposes an irradiation area corresponding to the cross-sectional shape data on the ultraviolet curable resin 31. According to the control, a part of the light is spatially modulated.

  That is, a drive signal for driving each pixel of the liquid crystal panel is supplied from the control unit 21 to the spatial light modulator 17 according to the cross-sectional shape data, and the spatial light modulator 17 performs irradiation based on the drive signal. The direction of polarized light to be transmitted is changed by changing the arrangement of the liquid crystal molecules of the pixel corresponding to the region. As a result, the spatial light modulator 17 spatially modulates the light passing through the liquid crystal panel, and uses the region corresponding to one pixel of the liquid crystal panel as a unit region for exposure, and converts light having a shape corresponding to the cross-sectional shape data to ultraviolet light. Projected onto the cured resin 31.

  The condenser lens 18 is composed of a lens group for correcting distortion when the light spatially modulated by the spatial light modulator 17 passes through the objective lens 19, and the light subjected to spatial light modulation by the spatial light modulator 17. Is focused on the front focal point of the objective lens 19. For example, distortion can be reduced by configuring each lens group so that the condenser lens 18 and the objective lens 19 are symmetrical optical systems.

  The objective lens 19 is composed of a lens group having one or a plurality of lenses, and forms an image of the light spatially modulated by the spatial light modulator 17 on the surface of the ultraviolet curable resin 31.

  Here, the objective lens 19 collects the light beam from the beam scan optical system when, for example, the beam exposure from the beam scan optical system (not shown) is performed together with the batch exposure with the light from the light source 12. The light beam is configured to be scanned at a uniform speed on the surface of the ultraviolet curable resin 31, that is, to be scanned at a uniform scanning linear velocity on the surface of the ultraviolet curable resin 31.

  For example, the objective lens 19 has an image height Y proportional to the incident angle θ and a so-called fθ having a relationship (Y = f × θ) in which the product of the focal length f and the incident angle θ becomes the image height Y. A lens is used. In other words, the fθ lens is a lens designed so that the scanning speed of the scanned light beam is always constant regardless of the incident position on the lens. By using such an objective lens 19, it is possible to prevent a difference between the design shape due to the variation in the scanning linear velocity and the actual shape of the hardened layer, thereby realizing high-definition modeling. The objective lens 19 may be a lens having a normal condensing function instead of the fθ lens.

  The work unit 20 includes a storage container 32, a stage 33, and a drive unit 34.

  The storage container 32 stores the liquid ultraviolet curable resin 31.

  The stage 33 is immersed in the ultraviolet curable resin 31 of the storage container 32, and is movable at least in a vertical direction (direction of arrow Z in FIG. 1) perpendicular to the liquid surface that is the surface of the ultraviolet curable resin 31. Further, the stage 33 is movable in a direction along the liquid surface that is the surface of the ultraviolet curable resin 31 (that is, an XY direction perpendicular to the direction of the arrow Z). Here, assuming that the optical axis of the light irradiating the ultraviolet curable resin 31 via the spatial light modulator 17 is the Z direction, the stage 33 is formed on the stage 33 in a direction orthogonal to the optical axis direction. The hardened layer is moved. Moreover, the drive part 34 moves the stage 33 to the direction (XY direction) along the surface of the ultraviolet curing resin 31 for every workpiece | work small area | region (FIG. 2) mentioned later.

  The drive unit 34 drives the container 32 and the stage 33 according to the control of the control unit 21. For example, the driving unit 34 exposes the ultraviolet curable resin 31 in accordance with the cross-sectional shape data of the three-dimensional model, and moves the stage 33 downward in the vertical direction one step at a time as one hard layer of the three-dimensional model is formed. To drive. The drive unit 34 drives the container 32 in the vertical direction so that the surface of the ultraviolet curable resin 31 coincides with the rear focal position of the objective lens 19.

  The control unit 21 controls the light source 12 to turn on / off light emission from the light source 12, controls the shutter 13 to turn on / off the exposure of the ultraviolet curable resin 31, and controls the drive unit 34. The container 32 and the stage 33 are driven by control. Further, the control unit 21 drives each pixel of the spatial light modulator 17 based on the cross-sectional shape data of the three-dimensional model so that the pixel of the spatial light modulator 17 corresponding to the irradiation region transmits light. Is supplied to the spatial light modulator 17.

  Moreover, the control part 21 divides | segments the whole workpiece | work area | region which is the whole area | region where the optical modeling operation | work is performed, for example, forms a hardened layer by performing collective exposure for every small workpiece | work area | region. Each part of the optical modeling apparatus 11 is controlled so that optical modeling is performed by the tiling method.

  With reference to FIG. 2, the optical shaping by the tiling method will be described.

  FIG. 2A shows the entire work area, which is the entire area where the optical modeling work is performed, and FIG. 2B shows a small work area that is a part of the entire work area.

  In FIG. 2, the vertical and horizontal dimensions of the entire work area are 10 cm × 10 cm, and the vertical and horizontal dimensions of the small work area are 1 cm × 1 cm. That is, the entire work area is divided into 10 × 10 small work areas in the vertical and horizontal directions.

  As shown in FIG. 2A, the hatched area near the center of the entire work area is an exposure area corresponding to the cross-sectional shape data of the three-dimensional model, and is the second line from the bottom of this work area. The work small area in the third column from the left is enlarged and shown in FIG. 2B. In FIG. 2B, a contour line based on the cross-sectional shape data of the three-dimensional model is indicated by a two-point difference line, and light is irradiated to a unit region that is hatched inside the contour line.

  For example, if the pixels of the spatial light modulator 17 are arranged so that the vertical × horizontal is 1000 pixels × 1000 pixels, as shown in FIG. 2B, the work small area is a pixel of the spatial light modulator 17. Accordingly, the vertical × horizontal is divided into 1000 × 1000 unit areas (that is, an area corresponding to one pixel of the spatial light modulator 17). Since the vertical and horizontal dimensions of the work small area are 1 cm × 1 cm, the vertical and horizontal dimensions of the unit area are 10 μm × 10 μm.

  Thus, in stereolithography by the tiling method, by reducing the range irradiated with light via the spatial light modulator 17 and sequentially exposing a plurality of work subregions arranged in a tile shape, The unit area can be made finer than when the entire work area is exposed at once. Thereby, a hardened layer can be formed with high precision and by extension, the dimensional accuracy of a three-dimensional model can be improved.

  Here, generally, the ultraviolet curable resin 31 contracts at a contraction rate of, for example, about 7% when cured by being irradiated with light. When the ultraviolet curable resin 31 is cured and shrunk in this way, when a small work area is exposed and the shrinkage of the ultraviolet curable resin 31 is proceeding (before complete curing), it is adjacent to the work small area. When the work small area to be exposed is exposed, the curing shrinkage of the UV curable resin 31 in the previously exposed work small area affects the UV curable resin 31 in the adjacent work small area, causing warping and deformation. was there.

  With reference to FIG. 3, the influence by the ultraviolet curing resin 31 being cured and contracted will be described.

  FIG. 3A shows a first work small area that is exposed first, and FIG. 3B shows a first work small area and a second work area that is exposed next to the first work small area. A work sub-region is shown.

  In FIG. 3, the region and direction affected by the curing shrinkage of the ultraviolet curable resin 31 are indicated by broken lines, and the cured layer formed by the ultraviolet curable resin 31 being cured and contracted is indicated by a solid line.

  As shown in FIG. 3A, when the first work small region is exposed, the ultraviolet curable resin 31 is cured and contracted so that the surrounding region is directed toward the center, thereby forming a cured layer.

  Then, when the second work small area is exposed while the hardening shrinkage of the first first work small area is proceeding, the first work small area is exposed as indicated by the white arrow shown in FIG. 3B. The second work small area receives a force that is pulled in the left direction, that is, in the direction of the first work small area. In this way, the second work small area is affected by the slight movement of the first work small area due to the hardening shrinkage force of the first work small area, and the entire exposure area (hatching in FIG. 2A is applied). If it occurs over a certain area, warping and deformation of the entire cured layer will occur. Thereby, the dimensional accuracy of a three-dimensional model may fall.

  Therefore, in the stereolithography apparatus 11, in order to avoid the influence caused by the curing and shrinkage of the ultraviolet curable resin 31 in the adjacent work small area, at least one work separated from the work after the predetermined work small area is exposed. The exposure order in which the small work areas are exposed is determined so that a small work area is exposed, that is, a work small area adjacent to the work small area is not exposed after the small work area is exposed. The

  With reference to FIG. 4, the exposure order of the work small area will be described.

FIG. 4 shows nine work small areas arranged so that the vertical × horizontal is 3 × 3. In each work small area, the control unit 21 creates work small area data. The codes T _{1 to} T ₉ for identifying each of the work small areas are added in the raster scan order from the lower left to the upper right.

As shown in FIG. 4A, the control unit 21 exposes the work small area T ₃ that is one work small area away from the work small area T ₁ so that the adjacent work small areas are not continuously exposed. The order of exposure is determined as follows. The control unit 21, the next exposing the work small area T _7, to determine the exposure order to expose a small work area distant work small area T _9.

After exposing the four work subregions T ₁ , T ₃ , T ₇ , and T ₉ as shown in FIG. 4A, as shown in FIG. 4B, the control unit 21 works between the work subregions. determining the exposure order to expose a small area T _5.

Thereafter, as shown in FIG. 4C, the control unit 21 performs a work small region T ₂ between the work small regions T ₁ and T ₃ , a work small region T ₄ between the work small regions T ₁ and T ₇ , and a work small. The exposure order is determined so that the work small area T ₆ between the areas T ₃ and T ₉ and the work small area T ₈ between the work small areas T ₇ and T ₉ are sequentially exposed.

  As described above, after a work small area is exposed, the exposure order is determined so that the work small area adjacent to the work small area is not exposed, so that the adjacent work small area is affected by hardening shrinkage. As described with reference to FIG. 3, the entire cured layer corresponding to one layer is not warped or deformed. Therefore, a hardened layer can be modeled with high accuracy, and a three-dimensional model formed by stacking such hardened layers can be modeled with high accuracy.

  Further, when the control unit 21 determines the exposure order, the time from when a small work area is exposed to when the small work area adjacent to the small work area is exposed is determined by the curing of the ultraviolet curable resin 31. The exposure order can be determined so as to be longer than the time required for.

By determining the exposure time in this way, for example, as shown in FIG. 4C, when exposing the work small area T ₂ between the work small areas T ₁ and T ₃ , the work small areas T ₁ and T _{Since 3} is completely cured, it is possible to prevent warping and deformation when the workpiece small region T ₂ is cured.

  Further, the control unit 21 is exposed first when the small work area of one exposure layer is exposed, the stage 33 is lowered by one layer, and the exposure area of the next layer is exposed. The exposure order of the exposure area of the next layer can be determined in accordance with the exposure order in the exposure area of the layer.

  For example, when the next layer is exposed in an exposure order that is unrelated to the exposure order in the exposure area of the previously exposed layer, the work small size that overlaps the work small area that is undergoing curing shrinkage in the exposure area of the previously exposed layer The area may be exposed. In this case, the work small area of the next layer may be affected by the hardening shrinkage of the work small area during the hardening shrinkage of the exposed area of the previously exposed layer, and warping or deformation in the Z direction of the three-dimensional model may occur. May occur.

  On the other hand, by determining the exposure order of the exposure area of the next layer according to the exposure order in the exposure area of the previously exposed layer, among the small work areas of the exposure area of the previously exposed layer Since the work sub-region of the layer exposed earlier is hardened in order, when the work sub-region of the next layer is exposed, the work sub-region of the previously exposed layer overlapping the work sub-region is cured. Thus, it is possible to avoid the influence of the hardening shrinkage of the small work area during the hardening shrinkage of the exposure area of the previously exposed layer, and it is possible to avoid warping or deformation of the three-dimensional model.

  Thus, when determining the exposure order, the time from when a small work area is exposed until the small work area adjacent to the small work area is exposed is necessary for curing the ultraviolet curable resin 31. By determining the exposure order so as to be more than the time, and by determining the exposure order of the exposure area of the next layer in accordance with the exposure order of the exposure area of the layer previously exposed, It can be modeled with high accuracy.

  Next, FIG. 5 is a flowchart for explaining processing for performing optical modeling by the optical modeling apparatus 11 of FIG.

  For example, when the three-dimensional shape data of the three-dimensional model created by CAD is input to the optical modeling apparatus 11 and an operation for starting the optical modeling is performed, in step S11, the control unit 21 creates the three-dimensional model created by CAD. A program for converting the three-dimensional shape data of the model into STL is executed, and the three-dimensional shape data of the stereo model is converted into STL.

  After the process of step S11, the process proceeds to step S12. The control unit 21 creates cross-sectional shape data of the three-dimensional model from the three-dimensional shape data converted into STL, and the process proceeds to step S13. Further, when creating the cross-sectional shape data of the three-dimensional model, for example, the posture and orientation of the three-dimensional model are determined, and data for modeling a member for preventing the falling of the three-dimensional model during modeling is created. .

  In step S <b> 13, the control unit 21 divides the cross-sectional shape data of one layer to be processed (for example, the cross-sectional shape data of the lowest layer first) according to the work small region, and the work small region data is divided. Create (generate).

  After the process of step S13, the process proceeds to step S14, and as described with reference to FIG. 4, the control unit 21 makes at least one work small area separated from each other a target to be exposed next. The exposure order of the work small areas is determined, and the process proceeds to step S15.

  In step S15, the control unit 21 supplies the spatial light modulator 17 with a drive signal for driving each pixel of the spatial light modulator 17 so as to irradiate the unit area as an irradiation area with the light. 17 drives each pixel so that the light radiated | emitted from the light source 12 may pass the pixel corresponding to the unit area | region used as an irradiation area | region. Then, the control unit 21 opens the shutter 13 for a predetermined exposure time to expose the irradiation area on the surface of the ultraviolet curable resin 31.

  After the process of step S15, the process proceeds to step S16, and the control unit 21 determines whether exposure based on all the work small area data for one layer created in step S13 has been performed.

  In step S16, when the control unit 21 determines that exposure based on all the work small region data for one layer is not performed, the process proceeds to step S17, and the control unit 21 determines in step S14. In accordance with the exposure order, the drive unit 34 is controlled to move the stage 33 so that the work small area next to the work small area exposed in the previous step S15 is exposed.

  After the process of step S17, the process returns to step S15, and in accordance with the exposure order determined in step S14, the work small area next to the work small area exposed in the immediately preceding step S15 is set as the processing target. The process is repeated.

  On the other hand, when the control unit 21 determines in step S16 that the exposure based on all the small work area data for one layer has been performed, the process proceeds to step S18, and the control unit 21 is created in step S12. It is determined whether exposure based on all cross-sectional shape data has been performed.

  In step S18, when the control unit 21 determines that the exposure based on all the cross-sectional shape data is not performed, the process returns to step S13, and the next layer after the exposure performed in the immediately preceding steps S13 to S15. Hereinafter, the same processing is repeated with the cross-sectional shape data of the layer as the processing target.

  On the other hand, when the control unit 21 determines in step S18 that the exposure based on all the cross-sectional shape data has been performed, the three-dimensional model is completed, and the process ends.

  As described above, the optical modeling apparatus 11 determines the exposure order of the work small areas so that at least one work small area separated from each other is a target to be exposed next, thereby making the hardened layer highly accurate. Modeling can be performed, and as a result, a three-dimensional model can be modeled with high accuracy.

  By using such an optical modeling apparatus 11, prototypes of microchips, connectors, microcapsules, etc., or various fine parts can be modeled.

  As the spatial light modulator 17, in addition to a transmissive liquid crystal panel, a digital micromirror device (DMD: Digital Micromirror Device) in which a plurality of minute reflecting mirrors whose inclination angles change according to an input signal is arranged. Alternatively, a reflective liquid crystal element (LCOS: Liquid Crystal On Silicon) or the like may be used. When a digital micromirror device is used, each micromirror corresponds to one unit region, and it is not necessary to provide the polarizing plate 14.

  In the present embodiment, the drive unit 34 moves the stage 33 in the XY direction, so that the hardened layer formed on the stage 33 is moved, and a plurality of work pieces arranged in a tile shape are moved. Although the regions are sequentially exposed, an optical system that irradiates light vertically toward the surface of the ultraviolet curable resin 31 instead of moving the stage 33, that is, the light source 12, the shutter 13, the polarizing plate 14, and the beam integrator 15. , A mirror 16, a spatial light modulator 17, a condensing lens 18, and an objective lens 19 are moved in the XY direction to move a plurality of small work areas arranged in a tile shape. May be sequentially exposed.

  In FIG. 4, the work small area separated by one work small area is the work small area to be exposed next. However, the work small areas separated by one work small area or more, for example, two or three or more work small areas are separated. The exposure order may be determined by setting the area as a work small area to be exposed next. The exposure order may be an order other than the raster scan order, for example, a clockwise order.

  Further, the irradiation region on the surface of the ultraviolet curable resin 31 may be exposed collectively through the spatial light modulator 17, and beam scan exposure may be performed to scan the light beam along the outline of the irradiation region. . By combining batch exposure and beam scan exposure, a three-dimensional model can be modeled with higher accuracy.

  Needless to say, the workpiece small region is not limited to a square, and the dimension in the X direction may be different from the dimension in the Y direction.

  In addition to the optical modeling apparatus 11 that performs optical modeling by the free liquid surface method, which is a method of irradiating light that has been spatially modulated by the spatial light modulator 17 from above the ultraviolet curable resin 31, for example, a space It can be applied to an optical modeling apparatus that performs optical modeling by a regulated liquid level method, which is a method of irradiating the light spatially modulated by the light modulator 17 to the interface between the ultraviolet curable resin 31 and the container 32.

  For example, the bottom surface of the container 32 is made of a material that transmits light, such as glass, and the light spatially modulated by the spatial light modulator 17 at the interface between the glass and the ultraviolet curable resin 31 is below the ultraviolet curable resin 31. Irradiated from. That is, the surface of the ultraviolet curable resin 31 irradiated with light according to the cross-sectional shape data of the three-dimensional model includes glass, the ultraviolet curable resin 31 and the interface.

  In the regulated liquid level method, the stage 33 is arranged so that the distance between the storage container 32 and the stage 33 is equal to the thickness of the cured layer for one layer, and the ultraviolet curable resin 31 is irradiated through the glass on the bottom surface of the storage container 32. By repeating the process of driving the stage 33 upward in the vertical direction so that the thickness of the hardened layer corresponding to one layer is formed step by step as the hardened layer of the three-dimensional model is formed by the applied light. A three-dimensional model is formed.

  Thus, by regulating the surface (interface) of the ultraviolet curable resin 31 irradiated with light with glass, the thickness of one layer of the cured layer is accurately modeled, so that the lamination accuracy can be improved. Thus, the three-dimensional model can be formed with high accuracy.

  The series of processes performed by the control unit 21 described above can be executed by hardware or can be executed by software. When a series of processing is executed by software, a program constituting the software executes various functions by installing a computer incorporated in dedicated hardware or various programs. For example, it is installed from a program recording medium in a general-purpose personal computer or the like.

  FIG. 6 is a block diagram showing an example of the hardware configuration of a computer that executes the above-described series of processing by a program.

  In a computer, a CPU (Central Processing Unit) 101, a ROM (Read Only Memory) 102, and a RAM (Random Access Memory) 103 are connected to each other via a bus 104.

  An input / output interface 105 is further connected to the bus 104. The input / output interface 105 includes an input unit 106 including a keyboard, a mouse, and a microphone, an output unit 107 including a display and a speaker, a storage unit 108 including a hard disk and nonvolatile memory, and a communication unit 109 including a network interface. A drive 110 for driving a removable medium 111 such as a magnetic disk, an optical disk, a magneto-optical disk, or a semiconductor memory is connected.

  In the computer configured as described above, the CPU 101 loads, for example, the program stored in the storage unit 108 to the RAM 103 via the input / output interface 105 and the bus 104 and executes the program. Is performed.

  The program executed by the computer (CPU 101) is, for example, a magnetic disk (including a flexible disk), an optical disk (CD-ROM (Compact Disc-Read Only Memory), DVD (Digital Versatile Disc), etc.), a magneto-optical disk, or a semiconductor. The program is recorded on a removable medium 111 that is a package medium including a memory or the like, or is provided via a wired or wireless transmission medium such as a local area network, the Internet, or digital satellite broadcasting.

  The program can be installed in the storage unit 108 via the input / output interface 105 by attaching the removable medium 111 to the drive 110. Further, the program can be received by the communication unit 109 via a wired or wireless transmission medium and installed in the storage unit 108. In addition, the program can be installed in the ROM 102 or the storage unit 108 in advance.

  The program executed by the computer may be a program that is processed in time series in the order described in this specification, or in parallel or at a necessary timing such as when a call is made. It may be a program for processing. Further, the program may be processed by a single CPU, or may be processed in a distributed manner by a plurality of CPUs.

  The embodiment of the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist of the present invention.

It is a block diagram which shows the structural example of one Embodiment of the optical modeling apparatus to which this invention is applied. It is a figure explaining the optical shaping by a tiling system. It is a figure explaining the influence by ultraviolet curing resin 31 hardening shrinkage. It is a figure explaining the exposure order of a workpiece | work small area | region. 5 is a flowchart for explaining processing for performing optical modeling by the optical modeling apparatus 11. It is a block diagram which shows the structural example of a computer.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 11 Stereolithography apparatus, 12 Light source, 13 Shutter, 14 Polarizing plate, 15 Beam integrator, 16 Mirror, 17 Spatial light modulator, 18 Condensing lens, 19 Objective lens, 20 Work part, 21 Control part, 31 UV curable resin, 32 container, 33 stage, 34 drive unit

Claims (5)

In the optical modeling apparatus for modeling the three-dimensional model by irradiating the surface of the photocurable resin with light according to the cross-sectional shape data of the three-dimensional model, forming a cured layer, and laminating the cured layer,
The workpiece small area which is the sectional shape data corresponding to the workpiece small area by dividing the sectional shape data of the three-dimensional model according to the workpiece small area obtained by dividing the entire workpiece area where the optical modeling work is performed into a plurality of areas. Data generation means for generating data;
An exposure order in which the work small areas are exposed in accordance with the work small area data is set such that at least one work small area is separated from the predetermined work small areas after the predetermined work small areas are exposed. A stereolithography apparatus comprising: a determination unit that determines that the light is exposed. The determination means has a time from when the predetermined small work area is exposed to when a small work area adjacent to the predetermined small work area is exposed is longer than a time required for curing the photocurable resin. The optical modeling apparatus according to claim 1, wherein the exposure order is determined so that The determining means, when forming the next hardened layer of the predetermined hardened layer according to the cross-sectional shape data of the three-dimensional model, according to the exposure order of the work subregion in the predetermined hardened layer, the next The optical modeling apparatus according to claim 1, wherein an exposure order of the work small regions in the hardened layer is determined. Batch exposure means for exposing the surface of the photocurable resin collectively based on the work small area data generated by the data generation means to form the cured layer;
In accordance with the order of exposure determined by the determining means, one of the collective exposure means and the cured layer is placed in the direction perpendicular to the optical axis of the light irradiated from the collective exposure means to the photocurable resin. The optical modeling apparatus according to claim 1, further comprising: a moving unit that moves the frame relative to each other. In the optical modeling method of modeling the three-dimensional model by irradiating the surface of the photocurable resin with light according to the cross-sectional shape data of the three-dimensional model to form a cured layer and laminating the cured layer,
The workpiece small area which is the sectional shape data corresponding to the workpiece small area by dividing the sectional shape data of the three-dimensional model according to the workpiece small area obtained by dividing the entire workpiece area where the optical modeling work is performed into a plurality of areas. Generate data,
An exposure order in which the work small areas are exposed in accordance with the work small area data is set such that at least one work small area is separated from the predetermined work small areas after the predetermined work small areas are exposed. A stereolithography method including the step of determining so that the light is exposed.

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