JP2010089438A - Method for forming slice image and shaping device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To form a plurality of slice images easily in a short period of time. <P>SOLUTION: In a method for forming slice images, a three-dimensional surface model 81 representing a curved surface along a reference plane is prepared at a slice image forming part. In succession, a shaped form image is formed in such a manner that every divisional region 821 is regarded as a pixel and the height at the divisional region 821 is employed as a pixel value by obtaining the height from the reference plane to the curved surface shown by the three-dimensional surface model 81 at each of a plurality of the divisional regions 821, which are set by dividing the reference plane 82 into two directions normal to each other by the predetermined pitch. After that, by repeatedly binarizing the shaped form image by threshold values successively increasing at the predetermined interval, a plurality of the slice images representing the sections of the three-dimensional surface model 81 by a plurality of planes parallel to the reference plane 82, are formed easily and in a short period of time. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a slice image generation method for generating a plurality of slice images from a three-dimensional surface model, and a modeling apparatus for modeling a surface having irregularities.

  Conventionally, optical modeling has been performed to form a desired three-dimensional model by irradiating the photocurable material with light while laminating the photocurable material. By slicing the three-dimensional surface model, slice image data corresponding to each layer of the modeled object is generated (see, for example, Patent Document 1 for generation of slice image data). Moreover, in patent document 2, the whole shape data which describes the whole three-dimensional shape to shape | mold is divided | segmented into several partial shape data which divided | segmented the whole shape into several in the lamination direction, and several partial shape data are made into multiple A method of shortening the data conversion time by transferring the data to the data conversion terminal and converting the data into modeling data is disclosed.

In Patent Document 3, in an optical modeling apparatus having a DMD in which a plurality of micromirrors are two-dimensionally arranged, a large amount of light is irradiated on a light irradiation region on a photosensitive member corresponding to each micromirror of the DMD. A technique for modeling in a short time by controlling the gradation is disclosed.
JP 2006-285262 A JP 2008-94001 A JP 2004-249508 A

  By the way, in the actual formation of the modeled object, outline data indicating the outline in the cross section of the three-dimensional surface model corresponding to each layer of the modeled object is created, and subsequently, the region corresponding to the modeled object and other areas in the image indicating the outline By assigning different values to regions, slice image data is generated. Generally, however, a 3D surface model is represented by a set of a large number of triangular patches, so when creating outline data In addition, a geometric operation for obtaining intersection lines between a large number of triangular patches and a plane corresponding to each layer of the modeled object is required for each layer, and it takes a long time to create all outline data. Further, as described above, time for converting outline data into slice image data is also required.

  The present invention has been made in view of the above problems, and an object thereof is to easily generate a plurality of slice images in a short time.

  According to the first aspect of the present invention, a slice for generating a plurality of slice images showing a cross section of the three-dimensional surface model by a plurality of planes parallel to the reference plane from a three-dimensional surface model expressing a curved surface along the reference plane. An image generation method comprising: a) obtaining a height from each of a plurality of divided areas set by dividing the reference plane in two directions perpendicular to each other at first and second pitches to the curved surface. A step of generating each of the divided areas as pixels, and generating an image having the height of each divided area as a pixel value; and b) binarizing the image repeatedly with a threshold that sequentially increases or decreases at a predetermined interval. And a step of generating a plurality of slice images.

  A second aspect of the present invention is the slice image generation method according to the first aspect, wherein the three-dimensional surface model is composed of a set of a plurality of planar elements.

  The invention according to claim 3 is the slice image generation method according to claim 2, wherein the step a) is perpendicular to the reference plane and a1) each of the plurality of areas set on the reference plane. A plane element that overlaps in the direction perpendicular to the reference plane and from the plane element that overlaps in the direction perpendicular to the reference plane and the area to which the respective divided areas belong, and a2) And a3) a step of obtaining the height in each of the divided regions using the planar element specified in the step a2).

  Invention of Claim 4 is the slice image generation method of Claim 2 or 3, Comprising: In said a) process, the said height in each said division area is four vertices of each said division area It is an average value of the height to the curved surface at the position.

  The invention according to claim 5 is the slice image generation method according to any one of claims 2 to 4, wherein in the step a), when there is a divided region whose height cannot be calculated, The height in the divided areas is determined based on the heights in two or more divided areas in the vicinity of the divided areas.

  The invention according to claim 6 is a modeling apparatus for modeling a surface having irregularities, wherein the three-dimensional surface includes a plurality of surfaces parallel to the reference plane from a three-dimensional surface model expressing a curved surface along the reference plane. A slice image generating unit that generates a plurality of slice images indicating a cross section of the surface model; and a modeling unit that performs modeling according to the plurality of slice images, wherein the slice image generating unit is a) the reference planes are perpendicular to each other The height from each of the plurality of divided regions set by dividing each of the two directions in the first and second pitches to the curved surface is obtained, and each divided region is regarded as a pixel, and the height in each divided region is determined. Generating an image having a pixel value as a pixel value, and b) repeatedly binarizing the image with a threshold value that sequentially increases or decreases at a predetermined interval. Performing the step of generating a slice image.

  Invention of Claim 7 is a modeling apparatus of Claim 6, Comprising: The some exposure area | region corresponding to each of these some division | segmentation area | region is set on the photosensitive material, Each in the said modeling part The cumulative amount of light irradiated to the exposure area is controlled to multiple gradations.

  According to the present invention, a plurality of slice images can be generated easily and in a short time.

  In the invention of claim 3, an image showing the height of the three-dimensional surface model can be generated in a short time, and in the invention of claim 4, the height in each divided region can be obtained with high accuracy.

  Further, in the invention of claim 5, even if there is a divided region whose height cannot be calculated, an image showing the height of the three-dimensional surface model can be generated with high accuracy. Then, formation of a molded article can be performed in a short time.

  FIG. 1 is a diagram showing a configuration of a modeling apparatus 1 according to the first embodiment of the present invention. The modeling apparatus 1 includes a base 10 installed horizontally, a stage 2 that holds a base substrate 9 serving as a base of a modeled object, and a supply unit that supplies a photosensitive material that is a liquid photocurable resin onto the base substrate 9. 3. A light beam is applied to the layer forming portion 4 for uniformly spreading the photosensitive material supplied on the base substrate 9 to form a layer having a predetermined thickness, and the layer of the photosensitive material formed on the base substrate 9. The light irradiation unit 5 that irradiates the stage 2, the stage moving mechanism 6 that moves the stage 2 relative to the light irradiation unit 5, the stage elevating mechanism 7 that raises and lowers the stage 2, and the alignment mark on the base substrate 9 are imaged. A camera 58 is provided.

  The supply unit 3, the layer formation unit 4, the light irradiation unit 5, the stage moving mechanism 6, the stage elevating mechanism 7, and the camera 58 are connected to the control unit 11, and these configurations are controlled by the control unit 11, whereby the base substrate 9. A model is formed on the top. The control unit 11 includes a storage unit 111 that stores various data, and a slice image generation unit 112 that performs various calculations and generates later-described slice image data used for modeling.

  The supply unit 3 drops and supplies a photosensitive material onto the base substrate 9, an arm 32 that supports the nozzle 31 at a position higher than the stage 2, and an arm 32 provided vertically on the base 10. Is provided with a support 33 that supports the base 10 horizontally. The arm 32 is rotatably supported on the upper portion of the column 33, and the nozzle 31 is attached to the tip of the arm 32. The arm 31 is rotated by a motor (not shown), so that the nozzle 31 can be moved between a position above the base substrate 9 and a position away from the base substrate 9.

  The nozzle 31 is connected to a pump 313 via a pipe 311 and a valve 312, and the pump 313 is connected to a material tank 316 via a pipe 314 and a valve 315. By controlling the pump 313 and the valves 312 and 315 by the control unit 11, a predetermined amount of photosensitive material is supplied from the nozzle 31 onto the base substrate 9.

  The layer forming unit 4 is a plate-like squeegee 41 perpendicular to the main surface of the base substrate 9 (and long in the X direction in FIG. 1), and the lower end of the squeegee 41 (that is, close to the main surface of the base substrate 9). A squeegee support portion 42 that supports the squeegee 41 while keeping the edge) parallel to the main surface of the base substrate 9, and a squeegee moving mechanism 43 that moves the squeegee 41 in the Y direction in FIG. Have. The squeegee moving mechanism 43 moves the squeegee 41 in the Y direction along the guide rail 432 when the ball screw mechanism is driven by the motor 431.

  The light irradiation unit 5 includes a light source 51 provided with a semiconductor laser that emits light (for example, light having a wavelength of about 300 nm or about 400 nm), and a micromirror array 54 in which a plurality of micromirrors are two-dimensionally arranged (for example, DMD (Digital Micromirror Device), hereinafter referred to as “DMD 54”), and the light beam from the light source 51 is spatially modulated by the DMD 54 and irradiated onto the base substrate 9.

  Specifically, the light beam emitted from the optical fiber 511 connected to the light source 51 is guided to the DMD 54 via the shutter 53 by the optical system 52. The DMD 54 derives a light beam formed by only the reflected light from the micromirrors in a predetermined posture (the posture corresponding to the ON state in the description of light irradiation by the DMD 54 described later) among the micromirrors. The light beam from the DMD 54 is guided to the mirror 56 through the lens group 55, and the light beam reflected by the mirror 56 is guided to the base substrate 9 by the objective lens 57.

  The stage moving mechanism 6 includes an X direction moving mechanism 61 that moves the stage 2 in the X direction, and a Y direction moving mechanism 62 that moves in the Y direction. The X-direction moving mechanism 61 includes a motor 611, a guide rail 612, and a ball screw (not shown). When the motor 611 rotates the ball screw, the Y-direction moving mechanism 62 moves in the X direction along the guide rail 612. Moving. The Y-direction moving mechanism 62 has the same configuration as the X-direction moving mechanism 61, and the stage 2 moves along the guide rail 622 in the Y direction when the motor 621 rotates with a ball screw (not shown). The stage moving mechanism 6 is supported by a stage elevating mechanism 7 on the base 10. When the stage elevating mechanism 7 is driven, the stage 2 moves in the Z direction, and the stage moving mechanism 6 is moved between the squeegee 41 and the stage 2. The interval is changed.

  FIG. 2 is a diagram showing the DMD 54. The DMD 54 is a spatial light modulation device in which a large number of micro mirrors 541 are arranged at equal intervals in two directions (row direction and column direction) perpendicular to each other, and according to data written in a memory cell corresponding to each micro mirror 541. In response to the input of the reset pulse, some of the micromirrors 541 are inclined by a predetermined angle due to the electrostatic field effect.

  FIG. 3 is a diagram showing a part of an irradiation region on the base substrate 9 (or on a layer of a photosensitive material described later formed on the base substrate 9). The minute irradiation area 542 on the base substrate 9 corresponding to each minute mirror 541 has a square shape like the minute mirror 541, and corresponds to the arrangement of the minute mirrors 541 in the X direction and Y direction in FIG. They are arranged at regular intervals at a predetermined pitch. In the present embodiment, the irradiation area is fixed on the base substrate 9 (precisely, a material layer described later), and one irradiation area is one exposure area serving as a unit of exposure on the base substrate 9. . In the light irradiation unit 5, the size of the irradiation region group can be changed.

  When the DMD 54 is controlled, data indicating ON or OFF of each micromirror 541 (hereinafter referred to as “cell data”) is transmitted from the control unit 11 in FIG. 1 to the DMD 54 and written into the memory cell of the DMD 54. Each micromirror 541 is changed to an ON state or an OFF state posture in synchronization with the reset pulse according to the cell data. As a result, the (micro) light beam applied to each micromirror 541 of the DMD 54 is reflected according to the direction in which the micromirror 541 is tilted, and the light to the irradiation region 542 on the base substrate 9 corresponding to each micromirror 541 is reflected. Irradiation is turned ON / OFF.

  That is, the light beam incident on the micromirror 541 that is turned on is reflected by the lens group 55 and guided to the corresponding irradiation region 542 on the base substrate 9. The light beam incident on the micromirror 541 in the OFF state is reflected to a predetermined position different from the lens group 55 and is not guided to the corresponding irradiation region 542.

  FIG. 4 is a diagram illustrating a flow of an operation in which the modeling apparatus 1 forms a modeled object. In the formation of a modeled object, first, the slice image generation unit 112 generates a plurality of slice image data (hereinafter also simply referred to as “slice images”) 84 used for modeling, and stores the data in the storage unit 111. (Step S11). The slice image 84 in the present embodiment is an image showing an irradiation region 542 to be irradiated with light from the light irradiation unit 5 (exposure image indicating ON / OFF of light irradiation) when forming each layer of the modeled object. Therefore, the slice image generation process will be described in detail after the description of the overall operation in the modeling apparatus 1.

  Subsequently, in response to a signal from the control unit 11, the camera 58 images the alignment mark on the base substrate 9, and image data is transmitted from the camera 58 to the control unit 11. The control unit 11 detects the relative position of the base substrate 9 with respect to the objective lens 57 based on the image data (that is, the distance between the reference position on the base substrate 9 and the objective lens 57 in the X direction and the Y direction), and the detection result Based on this, the stage moving mechanism 6 is controlled to move the base substrate 9 to a predetermined position (step S12).

  In addition, the control unit 11 determines the distance between the squeegee 41 and the base substrate 9 based on the focus adjustment information when the camera 58 acquires the image data (that is, the lower edge of the squeegee 41 and the base substrate 9. (Hereinafter, referred to as “squeegee gap”), and the stage elevating mechanism 7 is controlled based on the detection result and the slice pitch that is the thickness of each layer of the modeled object. The gap is adjusted so as to be the slice pitch (step S13). As will be described later, the slice pitch is specified in the process of step S11.

  FIG. A thru | or FIG. D is a diagram showing a state in which a photosensitive material is supplied onto the base substrate 9 and spread by the squeegee 41 to form a layer of photosensitive material (hereinafter referred to as “material layer”).

  When the adjustment of the squeegee gap is completed, first, the arm 32 is rotated to move to FIG. As shown in A, the nozzle 31 moves upward of the base substrate 9. At this time, the nozzle 31 is disposed above the edge of the base substrate 9 on the (−Y) side (that is, the side close to the initial position of the squeegee 41 shown in FIG. 5.A). Subsequently, the valves 312 and 315 are temporarily opened under the control of the control unit 11, and the photosensitive material from the material tank 316 is accurately dropped from the nozzle 31 onto the base substrate 9 by the pump 313 (Step S31). S14). In addition, FIG. In A (and FIGS. 5.B to 5.D), the photosensitive material on the base substrate 9 is shown with parallel oblique lines.

  Next, FIG. As shown in B, the arm 32 rotates from the position indicated by the two-dot chain line as indicated by the arrow 320b, and the nozzle 31 is retracted outside the base substrate 9, and the squeegee 41 is indicated by the two-dot chain line. It moves from the initial position along the main surface of the base substrate 9 in the direction indicated by the arrow 410b.

  Since the high-viscosity photosensitive material supplied on the base substrate 9 is higher than the squeegee gap and is accumulated on the base substrate 9, the lower end of the squeegee 41 and the base substrate 9 are formed along the main surface of the base substrate 9. By moving the squeegee 41 in the Y direction while keeping the distance from the main surface constant, the photosensitive material is evenly spread (ie, squeezed) on the base substrate 9 with a thickness equal to the squeegee gap. . As shown in B, a first material layer 91 of a photosensitive material is formed on the base substrate 9 (step S15). At this time, surplus photosensitive material is pushed out to a region outside the base substrate 9 (that is, on the stage 2).

  When the first material layer 91 is formed, the emission of the light beam from the light source 51 is started under the control of the control unit 11 and the DMD 54 is controlled to irradiate the material layer 91 with the light beam. (Step S16). Specifically, the control unit 11 writes cell data to the memory cell corresponding to each micromirror 541 of the DMD 54 based on the slice image 84 corresponding to the first material layer 91, and transmits a reset pulse to the DMD 54. As a result, each micromirror 541 has a posture corresponding to the data in the memory cell, and the light beam emitted from the light source 51 is spatially modulated by the DMD 54 to control the irradiation of light to each irradiation region 542.

  Thereby, light is irradiated from the light irradiation unit 5 to the irradiation region 542 in which the slice image 84 instructs light irradiation in the irradiation region 542 on the first material layer 91, and after the light irradiation for a predetermined time, the shutter is released. 53 is closed and emission of the light beam from the light source 51 is stopped (step S17). As a result, a part of the material layer 91 is cured to form a cured portion. A cured portion (the same applies to other cured portions described later) is present in the material layer 91 in a state of being cured by light irradiation, and is manifested as a three-dimensional shape after the uncured material is removed in a later step. It will be.

  In addition, when the range in which a molded article is formed is wider than the light irradiation range by the DMD 54, the irradiation range is moved by driving the stage moving mechanism 6 shown in FIG. 1, and light irradiation is repeated. In the above description, the nozzle 31 is moved. However, the height of the squeegee 41 is sufficiently low, and no problem occurs even when the photosensitive material is dropped from a position higher than the squeegee 41. Is not an obstacle to light irradiation from the light irradiation unit 5 to the material layer 91, the nozzle 31 may be fixed above the base substrate 9.

  When the formation of the hardened portion corresponding to the first slice image 84 is completed, the control unit 11 confirms whether or not the formation of the entire object has been completed, and then returns to step S13 for adjusting the squeegee gap (step S18). ) Move to formation of second material layer.

  In the formation of the second hardened portion from the base substrate 9, first, the stage elevating mechanism 7 is driven, the stage 2 is further lowered by the slice pitch, and the squeegee gap is made twice the slice pitch (step S13). Thereby, the distance between the lower end of the squeegee 41 and the surface of the first material layer 91 becomes equal to the slice pitch.

  Next, FIG. As shown in C, the squeegee 41 is moved to the initial position, the arm 32 is rotated, the nozzle 31 is positioned on the base substrate 9, and the photosensitive material is supplied from the nozzle 31 onto the base substrate 9 (step). S14). FIG. In C, the photosensitive material newly supplied with the parallel oblique line different from the first material layer 91 is shown. Then, FIG. As shown in D, the squeegee 41 moves and a second material layer 92 having a thickness equal to the slice pitch is formed on the existing material layer 91, and excess photosensitive material is placed outside the material layer 91. It is pushed out into the area (step S15).

  When the second material layer 92 is formed, light is irradiated to the specific irradiation region from the light irradiation unit 5 based on the slice image 84 corresponding to the second material layer 92, and the second cured portion is the first cured portion. Formed on the cure site. Note that the light applied to the surface of the second material layer 92 is shielded to some extent at the boundary between the material layer 91 and the material layer 92 and hardly reaches the first material layer 91. The cured state of the material layer is not affected.

  Thereafter, the material layer is formed by increasing the squeegee gap by the slice pitch, and the operation of irradiating the spatially modulated light beam (steps S13 to S17) is necessary (actually the same as the number of the remaining slice images). The number of times is repeated (step S18). As a result, the material layers are stacked, and a new cured portion is sequentially stacked on the existing cured portion, and the formation operation of the modeled object in the modeling apparatus 1 is completed. The base substrate 9 is conveyed to an external developing device, uncured material is removed, and a modeled object becomes apparent on the base substrate 9.

  Next, the slice image generation process in step S11 of FIG. 4 will be described. FIG. 6 is a diagram showing a flow of processing for generating a slice image. In the generation of the slice image, first, the three-dimensional surface model 81 shown in FIG. 7 is input and prepared in the shaped object image generation unit 1121 of the slice image generation unit 112 in FIG. 1 (step S111). The three-dimensional surface model 81 approximates and shows an ideal outer shape (surface) of a modeled object by a set of a plurality of triangular planar elements 811. In the modeling apparatus 1, a modeled object without a so-called overhang structure ( That is, when viewed from any direction along the base substrate 9, a modeled object in which there is no portion in which the upper part protrudes in the lateral direction from the lower part), in other words, a curved model approximately along the base substrate 9 is formed. Therefore, the three-dimensional surface model 81 represents a curved surface (including a plane) along the reference plane 82 corresponding to the upper surface of the base substrate 9. The planar element 811 may be a polygon other than a triangle.

  The three-dimensional surface model 81 is defined in the x, y, and z directions respectively corresponding to the X, Y, and Z directions in FIG. 1, and the modeling object image generation unit 1121 has a minimum drawing unit on the base substrate 9. The width (resolution) in the X direction and the Y direction of the region (that is, the exposure region) to be obtained is acquired, and the width Dx in the x direction and the width Dy in the y direction corresponding to these widths are determined (step S112). Then, as shown in FIG. 8, a reference plane 82 parallel to the x and y directions perpendicular to each other is divided into a reference plane 82 by dividing the reference plane 82 with a pitch of width Dx in the x direction and a pitch of width Dy in the y direction. A plurality of rectangular divided regions 821 (indicated by broken lines in FIG. 8) are set (step S113). In the actual modeling operation, the size of the irradiation region 542 is changed in accordance with the resolution acquired in step S112.

  Subsequently, the distance in the z direction from the center of each divided region 821 (which may be a representative position other than the center) to the curved surface indicated by the three-dimensional surface model 81 (hereinafter simply referred to as “the height in the divided region 821”). ") Is also required. Specifically, among a plurality (all) of planar elements 811 constituting the three-dimensional surface model 81, a planar element 811 that overlaps in the z direction perpendicular to the center of the divided area 821 and the reference plane 82 is specified. At this time, as described above, since the three-dimensional surface model 81 has a shape without an overhang structure, only one planar element 811 is specified, and the same xy coordinate value as the center of the divided region 821 is specified. The height in the divided area 821 is obtained from the z coordinate value of a point on the planar element 811 (that is, the intersection with the perpendicular in the center of the divided area 821). Each divided area 821 is regarded as a pixel, and the height in the divided area 821 (in this embodiment, represented by a positive real number) is assigned to the pixel as a pixel value. As a result, as shown in FIG. 9, an image (hereinafter referred to as “model object image”) 83 having the height in each divided region 821 as a pixel value is generated (step S114). In the present embodiment, the process of step S114a indicated by a broken-line rectangle in FIG. 6 is not performed.

When shaped object image 83 is generated, the binarization processing section 1122 of the slice image generation unit 112 of FIG. 1, a slice pitch S _p stored at preset in the storage unit 111 by the operator is read (Step S115) Subsequently, the minimum pixel value H _min and the maximum pixel value H _max (that is, the minimum height and the maximum height in the divided region 821) in the shaped object image 83 are acquired (Step S115). S116). Then, by dividing the actual pixel value range of the shaped object image 83 _(H max _{-H min)} at a slice pitch _{S p,} the slice number _{S t} are determined _{(i.e., (S t = (H} max -H _{min) / S} p)) (step S117). In this embodiment, as the slice number _{S t} is an integer _{((H max -H min) /} S p) slice pitch _S in _p is finely adjusted.

When the number of slices _St is obtained, the parameter S is set to an initial value 0 (step S118), and the first threshold value Th is obtained by calculating (H _min + S _p * S) (step S119). Then, the shaped object image 83 is binarized using this threshold Th, and a slice image is acquired (step S120). The slice image (data) 84 is stored in the storage unit 111.

Then, the binarization processing section 1122, the value of S confirms that not the slice count _{S t} (step S121), 1 is added to S (step _{S122), (H min + S} p The next threshold value Th is calculated by calculating * S) (step S119). Then, a binary slice image is acquired using this threshold Th (step S120). The process of step S122, S119, S120 are repeated until the value of S is sliced number _{S t} (i.e., loop processing expressed by "for _S = 0 to S _t" is performed) (step S121) FIG. A to FIG. As shown in C, a plurality of (actually many) slice images 84 are generated. FIG. A to FIG. In C, the pixels in the slice image 84 (hereinafter referred to as “ON pixels”) corresponding to the pixels in the shaped object image 83 having a pixel value larger than the threshold Th are shaded in parallel, and the ON pixels are light. The irradiation region 542 to be irradiated (irradiation region 542 in which light irradiation is turned ON) is shown.

  The threshold Th at the time of generating each slice image 84 is a value corresponding to the height of the uppermost material layer from the base substrate 9 at the time of light irradiation based on the slice image 84, and the model image 83 is The slice image 84 generated by binarization with the threshold Th indicates a cross section of the three-dimensional surface model 81 by a plane parallel to the reference plane 82 at a position in the z direction corresponding to the height ( However, since the three-dimensional surface model 81 indicates the outer shape of the modeled object, the slice image 84 is created so that the inside of the three-dimensional surface model 81 also indicates the part of the modeled object). Therefore, it is possible to form a modeled object having the same shape as the three-dimensional surface model 81 by irradiating light to the irradiation region 542 corresponding to the ON pixel in the slice image 84 when irradiating each material layer with light.

  Here, the slice image generation processing according to the comparative example will be described. In the method of the comparative example, in the three-dimensional surface model 931 shown in FIG. 11, the cross section of the three-dimensional surface model 931 at the height corresponding to each layer of the modeled object (the one-dot chain line denoted by reference characters α1 to α3 in FIG. 11). 12 is obtained, outline data indicating a two-dimensional outline 932 of the three-dimensional surface model 931 in the cross section is obtained as shown in FIG. 12, and an area corresponding to the modeled object in the image showing the outline 932 and other data By assigning a different value to the area, a slice image 933 is generated as shown in FIG.

  In general, since the three-dimensional surface model 931 is represented by a set of a large number of triangular patches, in the process of the comparative example, intersection lines between a large number of triangular patches and a virtual plane corresponding to each layer of the modeled object. It is necessary to perform geometric calculation for obtaining (outline) for each layer, and it takes a long time to create outline data. Further, the slice pitch is reduced (that is, the interval between a plurality of alternate long and short dash lines in FIG. 11 is reduced), or the triangular patch size in the three-dimensional surface model 931 is reduced as shown in FIG. The number of triangular patches increases.) When performing highly accurate modeling, the amount of calculation further increases. Further, as shown in FIG. 15, when the resolution in the slice image is increased (that is, the pixel size is decreased to increase the number of pixels), conversion from outline data to the slice image 933 (bitmap conversion) is performed. ) Takes longer. When combining these changes for realizing higher-accuracy modeling, the calculation time required for generating the slice image increases dramatically.

On the other hand, in the slice image generating unit 112 of the modeling apparatus 1, the modeled object image 83 is generated by obtaining the height from each of the plurality of divided regions 821 of the reference plane 82 to the curved surface indicated by the three-dimensional surface model 81. , slice pitch S by at intervals successively increasing threshold of _p binarizing repeatedly shaped object image 83, a plurality of slice images showing a cross section of a three-dimensional surface model 81 of a plurality of planes parallel to the reference plane 82 84 is generated.

  Therefore, when realizing high-precision modeling by narrowing the slice pitch (increasing the slice image), reducing the size of the triangle patch, increasing the resolution of the slice image, etc., or combining multiple 3D surface models on the same reference plane Depends on the number of pixels after creating a model image by calculation that refers to a triangular patch, even when placed on top or when the 3D surface model is complicated or enlarged. A plurality of slice images are generated by repeating the binarization processing for a certain processing time. Since the binarization process is simpler than the creation of outline data from a three-dimensional surface model and the conversion from outline data to slice image data, the slice image generation unit 112 has a comparison with the process of the comparative example. Thus, a plurality of slice images can be generated easily and in a short time (at high speed). In addition, even when a plurality of slice images are generated again by changing the slice pitch from the previous generation of the slice image, the generated model image (stored in the storage unit 111) is changed. A new slice image can be easily generated only by performing binarization processing with a threshold value corresponding to the slice pitch, and the time required for preparation of the slice image can be greatly shortened.

  Next, another example of slice image generation processing will be described. In the present processing example, the process of step S114a indicated by a broken-line rectangle in FIG. 6 is performed.

  Usually, when creating a 3D surface model with vector data in 3D CAD (Computer Aided Design), real number calculation is often performed for each coordinate indicated by the vector data. May occur, and a phenomenon may occur in which adjacent vertices in the adjacent triangle patches are slightly spaced apart from each other at the same position (it can be considered that the three-dimensional surface model is not closed). In this way, when the vertices are separated from each other, the plane element that overlaps the center of the divided area 821 in the z direction perpendicular to the reference plane 82 when obtaining the height in each divided area 821 in the process of step S114 of FIG. 811 may not be specified, and the height may not be calculated.

  Therefore, in the slice image generation process according to another example, when a plurality of divided areas 821 are set on the reference plane 82 in the process of step S113, a negative value is assigned to each divided area 821 as an initial pixel value. In addition, the pixel value is updated to the height obtained for the divided area 821 in the process of step S114. Therefore, after the process of step S114 is completed, the divided area 821 (pixel) having a negative pixel value can be easily recognized as a divided area whose height cannot be calculated (hereinafter referred to as “missing divided area”). Become.

  FIG. 16 is a diagram illustrating a model image 83a having a defect division area 821a. In FIG. 16, the negative pixel value assigned to the missing divided area 821 a is indicated as “XX”. In the slice image generation unit 112, the height in the defective divided region 821a is determined based on the height in the divided region 821 in the vicinity of the defective divided region 821a (step S114a). Specifically, the average value of the pixel values of the four adjacent regions 821b, 821c, 821d, and 821e of the defective divided region 821a (the average value of the pixel values of the two upper and lower or left and right divided regions 821 or The average value of the pixel values of the divided area 821 may be obtained.), And the pixel value of the missing divided area 821a is updated to this value. Then, a plurality of slice images are generated by sequentially binarizing the shaped object image 83a in which the pixel values of the missing divided region 821a are interpolated with a plurality of threshold values (FIG. 6: steps S115 to S122).

  Here, the slice image generation processing according to the comparative example described above corresponds to each layer of a modeled object when a phenomenon in which vertices that are originally in the same position are slightly separated from each other in adjacent triangular patches occurs. Some outlines of the 3D surface model that do not become closed occur, and a slice image cannot be generated. Therefore, in the method of the comparative example, it is necessary to confirm in advance whether or not the above phenomenon has occurred in the three-dimensional surface model, and to correct the three-dimensional surface model as necessary.

  On the other hand, in the slice image generation unit 112, even if there is a missing divided area 821a whose height cannot be calculated in the shaped object image 83a due to the above phenomenon, a plurality of divided areas in the vicinity of the missing divided area 821a. By calculation using the height in 821, the height in the missing divided area 821a is determined. As a result, a model image showing the height of the three-dimensional surface model can be generated accurately and easily without performing prior confirmation of the three-dimensional surface model as in the method of the comparative example. Can be formed appropriately.

  If the height in the defective divided region 821a is determined based on the height in two or more divided regions 821 in the vicinity of the defective divided region 821a, for example, a plurality of divided regions 821 in the vicinity of the defective divided region 821a. May be obtained as an average value of values obtained by multiplying the pixel value by a weighting factor corresponding to the relative positional relationship with the missing divided region 821a.

  Next, still another example of slice image generation processing will be described. FIG. 17 is a diagram showing a part of the flow of processing for generating a slice image, and shows processing performed in step S114 in the slice image generation processing of FIG.

  In the present processing example, when a plurality of divided regions 821 are set on the reference plane 82 (FIG. 6: step S113), a plurality of areas 822 are formed on the reference plane 82, as indicated by a bold solid line in FIG. Is set (FIG. 17: step S211). Each section 822 includes a plurality of divided areas 821, and each divided area 821 belongs to one of the sections 822. Subsequently, when each planar element 811 of the three-dimensional surface model 81 is vertically projected onto the reference plane 82, the planar element 811 at least partially included in each area 822 is in the z direction perpendicular to the reference plane 82. The overlapping plane element 811 overlapping with the area 822 is specified (step S212).

  When the overlapping plane element 811 is specified for each section 822, the section 822 to which each divided area 821 belongs is specified. From the overlapping plane element 811 that overlaps the section 822 in the z direction, the center of the divided area 821 and the z One planar element 811 that overlaps in the direction is identified (step S213). Then, the height in the divided area 821 is obtained from the z coordinate value of the point on the planar element 811 having the same xy coordinate value as the center of the divided area 821, and is given to the divided area 821 (pixel) as a pixel value. (Step S214). Thereby, a modeled object image 83 having the height in each divided region 821 as a pixel value is generated, and a plurality of slice images are generated by binarizing the modeled image 83 sequentially with a plurality of threshold values ( FIG. 6: Steps S115 to S122).

  As described above, in the slice image generation process of FIG. 17, a plurality of areas 822 are set on the reference plane 82, and the overlapping plane element 811 that overlaps each area 822 in the z direction is specified. When the plane element 811 that overlaps the center of each divided area 821 in the z direction is specified, only the overlapping plane element 811 of the section 822 to which the divided area 821 belongs is set as the search target, and the plane element specified from the search target. 811 is used to obtain the height in the divided area 821. Thereby, compared with the case where all the planar elements 811 are set as search targets, the planar elements 811 that overlap each divided region 821 in the z direction can be quickly identified, and the modeling showing the height of the three-dimensional surface model 81 The object image 83 can be generated in a short time. Note that the slice image generation processing in FIG. 17 may be combined with the above processing example (an example involving the processing in step S114a in FIG. 6) for correcting the height in the defective divided region.

  In the processing example described with reference to FIG. 6 (and FIG. 17), when the modeled object image 83 is generated, it is determined from the z coordinate value of the point on the planar element 811 that overlaps the center of each divided region 821 in the z direction. However, for the positions of the four vertices of each divided region 821, z coordinate values of points on the planar element 811 overlapping in the z direction are obtained in the same manner as described above, and the average value thereof is The height in the divided region 821 may be set. Thus, the height in each divided area 821 is the average value of the heights up to the curved surface indicated by the three-dimensional surface model 81 at the positions of the four vertices of the divided area 821, thereby the divided area 821. Can be obtained with high accuracy, that is, as a value approximated by the height of the ideal shape of the target object when generating the three-dimensional surface model 81 represented by the set of plane elements 811. it can.

  FIG. 18 is a diagram showing a modeling apparatus according to the second embodiment of the present invention. The modeling apparatus 1a of FIG. 18 applies a photosensitive resist, which is a positive photosensitive material, on a predetermined substrate by a predetermined thickness and is dried (hereinafter simply referred to as “photosensitive member”). This is an apparatus that irradiates light according to the shape of a desired modeled object, and the exposed photosensitive member is developed in a subsequent process, whereby a desired modeled object is manufactured.

  In the modeling apparatus 1a, the supply unit 3, the layer forming unit 4, and the camera 58 in the modeling apparatus 1 of FIG. 1 are omitted, and the configuration of the light irradiation unit 5a is different from the light irradiation unit 5 of FIG. In the modeling apparatus 1a, the functions of the slice image generation unit 112 and the storage unit 111 in the modeling apparatus 1 of FIG. 1 are realized by another computer 12 that is a component different from the control unit 11a. The stage 2, the stage moving mechanism 6 and the stage lifting mechanism 7 are the same as in FIG.

  Similar to the light irradiation unit 5 of FIG. 1, the light irradiation unit 5a includes a light source 51 and a DMD 54. Light from the light source 51 is spatially modulated by the DMD 54 and irradiated onto the photosensitive member 9a. Specifically, light emitted from the optical fiber 511 connected to the light source 51 is guided to the DMD 54 by an optical system (not shown). In the DMD 54, light formed only by reflected light from a micromirror in a posture corresponding to the ON state is derived. Light from the DMD 54 is guided to the half mirror 56 a through the lens group 55, and the reflected light is guided to the surface of the photosensitive member 9 a by the objective lens 57. As will be described later, in the modeling operation in the modeling apparatus 1a, the light irradiation area on the photosensitive member 9a moves relative to the photosensitive member 9a in the Y direction.

  In the modeling apparatus 1a of FIG. 18, the DMD 54 is inclined in the light irradiation unit 5a, and the arrangement direction of the irradiation region group 5420 on the photosensitive member 9a is the relative movement direction (that is, as shown in the upper part of FIG. , In the Y direction in FIG. In the upper part of FIG. 19, the irradiation region group 5420 is shown to be arranged in 4 rows and 5 columns, but in reality, a large number of irradiation regions are arranged in the row and column directions.

  The inclination of the irradiation region group 5420 with respect to the relative movement direction is a direction substantially in line with the relative movement direction of the two arrangement directions of the irradiation region group 5420 (that is, a direction corresponding to the column direction of the DMD 54). It is tilted so that the angle formed between the direction and the relative movement direction becomes a predetermined angle θ. At this time, the distance L1 in the direction perpendicular to the relative movement direction (that is, the X direction) of the irradiation regions located at both ends in one row (irradiation regions denoted by reference numerals 5421 and 5422 in the upper part of FIG. 19) is the irradiation region. It is made smaller than the pitch P1 in the row direction perpendicular to the column direction of the group 5420.

  18 includes an autofocus detection unit (hereinafter referred to as “AF detection unit”) 59 that detects the distance between the objective lens 57 and the surface of the photosensitive member 9a. The AF detection unit 59 includes a semiconductor laser 591 that emits laser light and a light receiving portion 592 that receives reflected light from the photosensitive member 9a, and the laser light emitted from the semiconductor laser 591 is reflected by the mirror 56b. The surface of the photosensitive member 9a is irradiated through the half mirror 56a and the objective lens 57. The reflected light of the laser beam from the photosensitive member 9a is guided to the AF detection unit 59 through the objective lens 57, the half mirror 56a, and the mirror 56b, and is sensitive to the objective lens 57 by the position where the light receiving unit 592 receives the reflected light. A distance from the surface of the member 9a is detected.

  FIG. 20 is a diagram illustrating a flow of an operation in which the modeling apparatus 1a forms a modeled object. For convenience of explanation, the following description will be made assuming that exposure is performed using only micromirrors arranged in 4 rows and m columns. As described above, since the irradiation region group 5420 moves relative to the photosensitive member 9a, the exposure region in the following description is a region fixed on the photosensitive member 9a.

  First, in the slice image generation unit 112 of the modeling apparatus 1a, a plurality of slice images are generated and input to the control unit 11a in the same manner as in step S11 of FIG. 4 (step S31). In the control unit 11a, the amount (cumulative amount) of light irradiated to one exposure region on the photosensitive member 9a and the depth at which the photosensitive resist in the exposure region irradiated with light is removed by development (hereinafter, “ A conversion table indicating the relationship with the processing depth ") is created and stored in advance, and a light dose necessary for each exposure region based on a plurality of slice images and the conversion table (in the following description, The “light irradiation amount” is called “exposure amount”) (step S32).

  Here, the plurality of divided regions (pixels) in the slice image respectively correspond to the plurality of exposure regions set on the photosensitive member 9a, and light is irradiated in the modeling apparatus 1a using the positive photosensitive resist. 10 is removed in the development process. A to FIG. In the slice image 84 shown in C, pixels that are not hatched in parallel indicate an exposure region to be irradiated with light (that is, have a pixel value that instructs light irradiation). In the control unit 11a, in each exposure region, the processing depth in the exposure region is determined by counting the number of pixels having a pixel value instructing light irradiation among the corresponding pixels of all slice images. An exposure amount corresponding to the processing depth of the exposure area is obtained based on the conversion table. In the conversion table, the exposure amount increases as the processing depth increases.

  In addition, information indicating the height (for example, the height from the substrate, hereinafter referred to as “reference height”) that requires the highest shape accuracy in the modeled object is input to the control unit 11a. In the modeling apparatus 1a, the position at which the light beams from the micromirrors in the ON state are converged in the photosensitive member 9a (so-called in-focus position, hereinafter referred to as “focusing position”) is the reference height of the photosensitive member 9a. The stage elevating mechanism 7 is controlled so as to match the distance, and the distance between the objective lens 57 and the photosensitive member 9a is adjusted (step S33). At this time, the distance between the objective lens 57 and the surface of the photosensitive member 9a is detected by the AF detection unit 59, whereby the distance between the objective lens 57 and the photosensitive member 9a is accurately adjusted.

  When the raising / lowering operation of the stage 2 is completed, the stage 2 starts to move in the (+ Y) direction under the control of the control unit 11a, and the irradiation region group 5420 is relatively and continuously in the (−Y) direction with respect to the photosensitive member 9a. (Step S34). Then, emission of light from the light source 51 is started, the DMD 54 is controlled in synchronization with the relative movement of the irradiation region group 5420, and an exposure operation is performed (step S35).

  FIG. 21 is a diagram for explaining how the DMD 54 is controlled in synchronization with the relative movement of the irradiation region group 5420. In FIG. 21, the irradiation regions group 5420 of one row at each stage of movement is shown with reference numerals I, II, III, IV, and V. The irradiation regions that are turned on are indicated by solid lines, The irradiated area is indicated by a broken line. In FIG. 21, reference numerals 542a, 542b, 542c, and 542d are given in order from the irradiation area located on the (+ Y) side, and the exposure area group 940 on the photosensitive member 9a is indicated by a two-dot chain line. The rightmost side of FIG. 21 shows the exposure amount in each exposure region.

  When the first cell data is written to the memory cell of each micromirror from the control unit 11a and the irradiation area group 5420 reaches a predetermined exposure start position on the photosensitive member 9a, the first reset pulse is transmitted from the control unit 11a. Is done. As a result, each micromirror of the DMD 54 is set in a posture according to the data of the memory cell, and ON / OFF of the light irradiation to the corresponding irradiation region is performed. For example, as shown on the leftmost side of FIG. 21 (the stage marked with symbol I), only the irradiation region 542d is turned on, and the other irradiation regions 542a to 542c are turned off.

  Immediately after the transmission of the reset pulse, the second cell data is written to the memory cell of each micromirror. Transmission of the reset pulse to the DMD 54 is performed in synchronization with an operation in which the stage moving mechanism 6 moves the stage 2. That is, when the irradiation area group 5420 moves from the first reset pulse by a distance of the pitch P2 in the relative movement direction of the exposure area group 940, the second reset pulse is transmitted to the DMD 54, and is the second from the left in FIG. As shown in (Step II), the irradiation areas 542c and 542d are turned on, and the other irradiation areas 542a and 542b are turned off.

  Subsequently, in the third reset pulse transmission, the irradiation regions 542b to 542d are turned on as shown in the third part from the left of FIG. In the fourth reset pulse transmission, all irradiation regions 542a to 542d are turned on as shown in (IV). Then, in the fifth reset pulse transmission, all irradiation regions 542a to 542d are turned off as shown in the fifth position from the left in FIG. As a result, light irradiation from a plurality of irradiation areas is performed on one exposure area in a superimposed manner (that is, multiple exposure is performed), and five gradation exposure is possible as shown on the rightmost side of FIG. Become. Since the irradiation region group 5420 is relatively moved, the light amount shown on the rightmost side in FIG.

  At this time, in the case where the column direction of the irradiation region group 5420 is arranged in a direction parallel to the relative movement direction, and there is a small structural gap between each micro mirror of the DMD 54, the column between each irradiation region is between There is a region where no light is irradiated. On the other hand, in the modeling apparatus 1a, since the irradiation region group 5420 continuously moves relative to the tilted state as shown in the upper part of FIG. 19, the accumulated light quantity is almost in the X direction as shown in the lower part of FIG. It will be distributed uniformly. Accordingly, it is possible to appropriately irradiate light between the exposure regions adjacent in the X direction.

  When the irradiation region group 5420 passes through the last exposure region on the (−Y) side, emission of light from the light source 51 is stopped (step S36), and movement of the stage 2 is stopped (step S37). If the width of the exposure region group in the X direction is large, the irradiation region group 5420 is step-moved in the X direction (that is, sub-scanning), and the exposure operation is repeated. Thereafter, steps S36 and S37 are executed. The photosensitive member 9a exposed by the above operation is developed in another apparatus outside the modeling apparatus 1a, and the photosensitive resist having a depth corresponding to the accumulated light amount in each exposure area is removed. Thereby, the modeled object indicated by the three-dimensional surface model is completed.

  As described above, in the modeling apparatus 1a according to the second embodiment, each exposure region on the photosensitive member 9a is synchronized with the relative movement of the irradiation region group 5420 corresponding to the unit of modulation with respect to the photosensitive member 9a. By performing ON / OFF control of light irradiation to a plurality of irradiation areas that pass through, the cumulative amount of light irradiated to the exposure area is controlled in multiple gradations. That is, multi-tone exposure is realized by superposing exposure with a plurality of irradiation areas on one exposure area. As a result, a modeled object can be formed in a short time without laminating a photosensitive material as in the modeling apparatus 1 of FIG.

  Further, in the modeling apparatus 1 a, the DMD 54 is inclined so that the distance in the direction perpendicular to the relative movement direction of the irradiation regions located at both ends of the irradiation region group 5420 is smaller than the pitch in the row direction of the irradiation region group 5420. Therefore, the DMD 54 can be easily controlled as in the case where the DMD 54 is not tilted, and the influence of the gap between the micromirrors on the shape of the modeled object can be suppressed.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made.

  In the binarization processing unit 1122, a plurality of slice images are generated by repeating the binarization processing with a threshold that sequentially increases at intervals of a predetermined slice pitch. In steps S119 to S122 in FIG. A threshold value that sequentially decreases at intervals may be obtained, and a plurality of slice images may be generated.

  In the modeling apparatus 1 in FIG. 1, the function as a modeling unit that performs modeling according to a plurality of slice images is the control unit 11, the stage 2, the supply unit 3, the layer forming unit 4, the light irradiation unit 5, the stage moving mechanism 6, and the stage. 18 is realized by the control mechanism 11a, the stage 2, the light irradiation unit 5a, the stage moving mechanism 6, and the stage lifting mechanism 7. In the modeling apparatus 1a of FIG. 18, the modeling unit has various configurations. It is possible to realize. For example, a stage is provided in a processing tank in which a liquid photosensitive material is stored, and molding light is irradiated to the photosensitive material on the stage from a light irradiation unit provided above the processing tank while sequentially descending the stage. The modeling part which forms a molded article by doing may be provided.

  In the modeling apparatus 1 of FIG. 1, the cumulative amount of light irradiated on each irradiation region 542 may be controlled in multiple gradations, similarly to the modeling apparatus 1 a of FIG. 18. Specifically, a reset pulse is transmitted from the control unit 11 to the DMD 54 for a predetermined time, and the number of times each micromirror 541 is turned on (corresponding to the accumulated time of each micromirror 541 being on). By controlling accurately, the cumulative amount of light irradiated to each irradiation region 542 is controlled in multiple gradations. Further, the unit time is divided into 1: 2: 4: 8: 16 time frames, and the reset pulse is transmitted only once at the beginning of each time frame, so that gradation control (in the above example, 32 gradations). May be performed). Furthermore, in the modeling apparatus 1a that performs the exposure of superposition with a plurality of irradiation areas for each exposure area, the amount of light irradiated to the exposure area when each irradiation area passes is changed to multiple gradations. Also good.

  The configuration of the light irradiation unit 5 (and the light irradiation unit 5a) may be appropriately changed as long as a minute light spot can be formed on the material layer (the photosensitive member 9a). For example, a spatially modulated light beam may be generated by a liquid crystal shutter or the like, and the divided laser beams are individually modulated to generate a multi-beam (one-dimensional spatially modulated light beam), a polygon mirror, You may scan by a galvanometer mirror. In addition, a plurality of light emitting diodes and the like are two-dimensionally arranged as a light source, and each light emitting diode is irradiated ON / OFF in a state where the arrangement direction of the light irradiation region group corresponding to the light emitting diode group is inclined with respect to the relative movement direction. Multiple exposure may be performed by controlling in synchronization with the relative movement of the region.

  In the above embodiment, a modeled object having a convex (hemispherical) surface is formed based on the three-dimensional surface model 81 of FIG. 7. For example, the modeling apparatus 1, 1 a includes a microlens, a diffusion plate, and the like. When forming a molding die used for manufacturing the optical element, a three-dimensional surface model expressing a concave curved surface along a reference plane is prepared, and a shaped object having a concave surface is formed. In addition, the formation target in the modeling apparatuses 1 and 1a may be an array in which grooves having a V-shaped cross-section along the Z direction may be arranged. It can be understood that a curved surface (including a plane) along the reference plane is expressed. As described above, the modeling apparatuses 1 and 1a can be used for modeling a surface having various irregularities. In addition, the plurality of slice images generated by the slice image generation unit 112 may be used for purposes other than the formation of a modeled object.

It is a figure which shows the structure of the modeling apparatus which concerns on 1st Embodiment. It is a figure which shows DMD. It is a figure which shows the irradiation area | region on a base substrate. It is a figure which shows the flow of the operation | movement which forms a molded article. It is a figure which shows formation of the material layer on a base substrate. It is a figure which shows formation of the material layer on a base substrate. It is a figure which shows formation of the material layer on a base substrate. It is a figure which shows formation of the material layer on a base substrate. It is a figure which shows the flow of the process which produces | generates a slice image. It is a figure which shows a three-dimensional surface model. It is a figure which shows the division area of a reference plane. It is a figure which shows a molded article image. It is a figure which shows a slice image. It is a figure which shows a slice image. It is a figure which shows a slice image. It is a figure which shows a three-dimensional surface model. It is a figure which shows the outline of a three-dimensional surface model. It is a figure which shows a slice image. It is a figure which shows a three-dimensional surface model. It is a figure which shows a slice image. It is a figure which shows a molded article image. It is a figure which shows a part of flow of the process which produces | generates a slice image. It is a figure which shows the structure of the modeling apparatus which concerns on 2nd Embodiment. It is a figure which shows the irradiation area group on a photosensitive member. It is a figure which shows the flow of the operation | movement which forms a molded article. It is a figure for demonstrating control of DMD.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,1a Modeling apparatus 2 Stage 3 Supply part 4 Layer formation part 5, 5a Light irradiation part 6 Stage moving mechanism 7 Stage raising / lowering mechanism 11, 11a Control part 81 3D surface model 82 Reference plane 83, 83a Modeling object image 84 Slice image 112 slice image generation unit 811 plane element 821, 821b, 821c, 821d, 821e divided area 821a missing divided area 822 area 940 exposure area group S114, S114a, S118 to S122, S212 to S214 Steps

Claims (7)

A slice image generation method for generating, from a three-dimensional surface model representing a curved surface along a reference plane, a plurality of slice images showing cross sections of the three-dimensional surface model by a plurality of surfaces parallel to the reference plane,
a) A height from each of a plurality of divided areas set by dividing the reference plane in two directions perpendicular to each other at first and second pitches to the curved surface is obtained, and each divided area is defined as a pixel. Considering the step of generating an image having the height in each of the divided regions as a pixel value;
b) generating a plurality of slice images by repeatedly binarizing the image with a threshold that sequentially increases or decreases at a predetermined interval;
A slice image generation method comprising: The slice image generation method according to claim 1,
A slice image generation method, wherein the three-dimensional surface model is constituted by a set of a plurality of planar elements. The slice image generation method according to claim 2,
Step a)
a1) identifying a planar element that overlaps each of the plurality of areas set in the reference plane in a direction perpendicular to the reference plane;
a2) identifying a plane element that overlaps each divided region in a direction perpendicular to the reference plane from a plane element that overlaps in a direction perpendicular to the reference plane and a section to which each divided region belongs;
a3) obtaining the height in each of the divided regions using the planar element specified in the step a2);
A slice image generation method comprising: The slice image generation method according to claim 2 or 3,
In the step a), the height in each divided area is an average value of the heights up to the curved surface at the positions of four vertices in each divided area. A slice image generation method according to any one of claims 2 to 4,
In the step a), when there is a divided region where the height cannot be calculated, the height in the divided region is determined based on the height in two or more divided regions in the vicinity of the divided region. A slice image generation method characterized by the above. A modeling apparatus for modeling a surface having irregularities,
A slice image generating unit that generates, from a three-dimensional surface model expressing a curved surface along a reference plane, a plurality of slice images showing cross sections of the three-dimensional surface model by a plurality of planes parallel to the reference plane;
A modeling unit that performs modeling according to the plurality of slice images;
With
The slice image generator
a) A height from each of a plurality of divided areas set by dividing the reference plane in two directions perpendicular to each other at first and second pitches to the curved surface is obtained, and each divided area is defined as a pixel. Considering the step of generating an image having the height in each of the divided regions as a pixel value;
b) generating a plurality of slice images by repeatedly binarizing the image with a threshold that sequentially increases or decreases at a predetermined interval;
The modeling apparatus characterized by performing. The modeling apparatus according to claim 6,
A plurality of exposure areas respectively corresponding to the plurality of divided areas are set on the photosensitive material,
The modeling apparatus characterized in that a cumulative amount of light irradiated to each exposure region in the modeling unit is controlled in multiple gradations.

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