JPS61116322A - Three-dimensional shape forming device - Google Patents

Abstract

PURPOSE:To form a highly accurate three-dimensional shape of high quality effectively and easily by irradiating two laser beams on a prescribed exposing position of a liquid light-curing hardening resin material so as to be superposed. CONSTITUTION:A laser beam 32 radiated from a laser device 31 is divided into two laser beams 32a, 32b by an optical branch 33 and the two laser beams 32a, 32b are modulated by respective photomodulators 36, 37 on the basis of a shape data signal forming a three-dimensional shape, converted into proper beam diameters by lenses 38, 39 and 40, 41, polarized by a rotary polyhedral mirror 42, and irradiated so as to be superposed to the liquid light-curing resin material 49 stored in a resin storing vessel 48 through f lenses 43, 44 and scanning reflectors 45-47 from respectively different directions to execute main scanning. In this case, a supporting board 50 mounting the vessel 48 is also moved on the basis of the three-dimensional shape forming data signal and the resin material 49 is selectively exposed and hardened.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a three-dimensional shape forming apparatus for forming a three-dimensional model shape for displaying three-dimensional three-dimensional information using a liquid photocurable resin material and a laser beam irradiation means. In particular, the present invention relates to an apparatus configuration for forming a highly accurate, high-quality three-dimensional model shape by exposing and curing a liquid photocurable resin material by superimposing laser beams from two different directions.

As methods for displaying three-dimensional stereoscopic information, stereoscopic display using holography, perspective view display, projection view display, contour line display, etc. have been developed and are generally widely used. With the exception of holography, all of these methods can convert three-dimensional information into two
It includes a procedure for converting into dimensional information, and is not necessarily a satisfactory technique for intuitively grasping and fully understanding the displayed three-dimensional shape.

In this respect, the holography is visually and intuitively more advantageous than the above techniques, but it requires a reproduction device to obtain a three-dimensional shape, and it is difficult to display non-existent virtual objects. .

For this reason, in order to intuitively grasp 3D information and display it in an easy-to-understand manner, it is best to create a 3D shape such as a model.

As a method for forming a three-dimensional model shape relatively easily, a photocurable resin material is supplied stepwise into a resin material storage container, and each time the resin material is supplied, the photocurable resin material is irradiated with a laser beam or the like. A method has been proposed in which a complex three-dimensional model shape is formed in a layered manner by selectively photocuring.

However, in such a forming method, the photocurable resin material is cured when the light energy (exposure energy) of the laser beam irradiated to the photocurable resin material is equal to or higher than a certain threshold value. However, a small change in this threshold value causes a change in the hardened portion, which poses a problem that becomes a major hindrance to forming a highly accurate three-dimensional shape, and there is a need to eliminate these obstacles.

[Conventional technology]

Conventionally, as a method for forming a model shape that displays three-dimensional stereoscopic information using a photocurable resin material using a laser beam irradiation means, as shown in FIG. 13, a liquid photocurable resin material 3 is filled. The elevating support table 2 in the storage container 1 is lowered by a predetermined distance, and one portion of the photocurable resin material 4 is supplied by overflowing onto the elevating support table 2.

After that, - a laser beam 5 is applied to the essential photocurable resin material 4 using a first information pattern signal among cross-sectional information pattern signals obtained by dividing the model shape to be created into several slices, for example; Alternatively, the photocurable resin material 4 side is moved and scanned in the X and Y directions to irradiate it with a beam and selectively expose and cure it to form the first cured resin layer 4a.

Next, as shown in FIG. 14, the lifting support 2 is lowered by a predetermined distance again, and a new second layer of photocurable resin material 6 is placed on the first cured resin layer 4a on the lifting support 2. is supplied in the same manner as described above, and the photocurable resin material 6 is similarly irradiated with the laser beam 5 according to the second information pattern signal as shown in FIG. A cured resin layer 6a is formed.

Thereafter, in the same manner as shown in FIG. 16, a new third layer of photocurable resin material 7 is further supplied onto the second cured resin layer 6a on the lifting support table 2, and the photocurable resin is As shown in FIG. 17, the material 7 is irradiated with the laser beam 5 in accordance with the third information pattern signal, and is selectively exposed and cured to form a third cured resin layer 7a. A laminated three-dimensional cured resin image is formed in the photocurable resin material 3 .

This three-dimensional cured resin image is taken out from the liquid photocurable resin material 3 and the liquid photocurable resin material 3 is washed away with a dilute alkaline cleaning solution to obtain a desired three-dimensional joined body as shown in FIG. A model shape 8 for displaying information is being created.

[Problem that the invention seeks to solve]

However, in the method of forming a three-dimensional three-dimensional shape using a laser beam irradiation means as described above, the laser beam 5 irradiated onto the liquid photocurable resin material 3 absorbs its light energy ( The exposure energy is transmitted in the depth direction while being absorbed, and the value of the exposure energy has a characteristic of continuously attenuating and changing in the depth direction of the resin material 3.

On the other hand, the liquid photocurable resin material 3 has a characteristic that only the portion irradiated with the laser beam 5 whose exposure energy is above a certain threshold value is exposed and cured. From the characteristic relationship, the laser beam 5 to be irradiated
Due to the slight change in the exposure energy threshold, the boundary area between the exposed hardened part and the unexposed hardened part in the depth direction of the resin material 3 is disturbed, and the entire hardened part changes to form a three-dimensional structure with high precision. There was a drawback that it became an obstacle in forming the shape.

[Means for solving problems]

The above problem can be solved by irradiating the liquid photocurable resin material supplied to the resin storage container with a beam using a laser optical system.
In the apparatus for selectively curing the photocurable resin material to form a three-dimensional shape, two laser beams from the laser optical system are applied to the liquid photocurable resin material, respectively, based on the three-dimensional shape forming data. This problem is solved by the three-dimensional shape forming apparatus according to the present invention, which is configured to emit irradiation in a superimposed manner from different directions.

[Effect]

That is, in the present invention, as shown in the partial cross-sectional perspective view of FIG. and the other second laser beam 22 is irradiated in a direction perpendicular to the side surface of the resin material 23 based on the shape forming data, and both beams 21.
22 are selectively scanned in such a manner that they overlap inside the resin material 23 to perform exposure and curing.

In this way, the irradiation direction of the second laser beam 21 (
The exposure energy in the depth direction) 24 with respect to the resin material 23 is shown by the cross section 27, and as shown by the A distribution curve in the exposure energy distribution diagram of FIG.
The attenuation is continuously changed in the depth direction 24 of 3.

On the other hand, the exposure energy of the beam 21 in the main scanning direction 25 and the sub-scanning direction 26 horizontally orthogonal to the main scanning direction 25 is transmitted by an optical modulator and a laser optical system between the exposed area and the unexposed area. The distribution becomes steep depending on the laser beam diameter.

Furthermore, the exposure energy in the irradiation direction 26 of the second laser beam 22 is B in the exposure energy distribution diagram in FIG.
As shown by the distribution curve, the depth direction 2 of the resin material 23
4, the distribution is dependent on the laser beam diameter, and in the main scanning direction 25, the distribution is dependent on the rise of the optical modulator. On the other hand, in the sub-scanning direction 26, the distribution characteristics are similar to the distribution of the first loser beam 21 in the depth direction.

In this way, the two first and second laser beams 21, 2
2, a three-dimensional exposure energy distribution occurs inside the resin material 23, and the total exposure energy distribution at the cross section 27 is A as shown in FIG.

The characteristics of the B distribution curve lead to the characteristics of the C distribution curve, resulting in an exposure energy distribution having a steep changing region on the surface of the resin material 23 and at the lower end of exposure.

Therefore, the resin material 23 after the exposure operation as described above has a region of steep change at the boundary between the exposed portion and the unexposed portion in any of the depth direction 24, the main scanning direction 25, and the sub-scanning direction 26. Exposure energy distribution occurs and these first,
Even if the threshold value D (see FIG. 3) of each exposure energy of the second laser beam 21, 22 changes slightly, it is possible to form a three-dimensional shape with high precision and high quality.

〔Example〕

Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a schematic perspective view showing a first embodiment of a three-dimensional shape forming apparatus according to the present invention.

In the figure, 31 is a laser device that emits a laser beam 32, 33 is an optical sentinel, 34.35 is a reflecting mirror, and 36.3 is a laser device that emits a laser beam 32.
7 is an optical modulator, 38 to 41 are lenses, 42 is a rotating polygon mirror, and 43 and 44 are fθ lenses, which can set the focus of the laser beam 32 on the irradiation surface of the resin material, and the laser beam at the focus The beam diameter can be made very small, and
Concentrated irradiation of beam exposure energy Ee becomes possible. 4
5, 46, and 47 are scanning reflecting mirrors, which constitute a laser optical system.

Further, 48 is a resin storage container that accommodates the liquid photocurable resin material 49, 50 is a support base, 51 is a moving mechanism unit that moves the support base 50 in the directions of arrows A and B, and 52 is a liquid light This is a resin material supply section including a supply port 53 having an elongated shape through which a curable resin material 49 is supplied.

In such a device configuration, the laser beam 32 emitted from the laser device 3
two laser beams 32a, as shown by 33;
It is divided into 32b.

These two laser beams 32a and 32b are modulated and controlled by optical modulators 36 and 37, respectively, based on shape data signals that form a three-dimensional shape, and are converted into light-transmitting beam diameters by lenses 38, 39 and 40, 41. , is deflected by a rotating polygon mirror 42, and is further deflected by fθ lenses 43 and 44.
and scanning reflectors 45, 46. and 47, the liquid photocurable resin material 49 in the resin container 48 is irradiated in a superimposed manner from different directions, and is further main-scanned.

At this time, the support stand 5 on which the resin storage container 48 is placed
0 also moves the moving mechanism section 5 based on the three-dimensional shape formation data signal.
1 is controlled and simultaneously moved in the direction of the arrow, and selective exposure and curing is performed.

Now, in order to form a desired three-dimensional model shape for displaying three-dimensional three-dimensional information by applying the above-described apparatus, first, as shown in FIG.
The main scanning position of one of the second laser beams 21 relative to 8 and the elongated supply port 53 of the resin material supply section 52 are spaced apart by l in the sub-scanning direction.
The sub-scanning by the moving mechanism section 51 and the supply of a certain amount of liquid photocurable resin material 49 from the supply port 53 of the resin material supply section 52 are started.

Next, as shown in FIG. 5, after starting the supply of the resin material 49, from the time when the resin container 48 has moved by a distance β or more from the supply start position of the resin material 49 by sub-scanning, data of the three-dimensional shape to be formed is determined. Then, the optical modulators 36 and 37 are driven by a shape pattern signal outputted from a control circuit (not shown), and the first loose beam 32a is directed perpendicularly to the surface of the supplied liquid photocurable resin material 49. Similarly, the side surfaces of the resin material 49 are irradiated with the second laser beams 32b to start exposure.

Here, the scanning of the first laser beam 32a is performed in the C direction as shown in FIG.
Scanning 2b is performed in the D direction conversely.

Furthermore, the timing of starting scanning is also different because it depends on the incident position of each laser beam 32a, 32b on the rotating polygon mirror 42, and the exposure of each part of the liquid photocurable resin material 49 with the two laser beams 32a, 32b is different. Although they are not simultaneous, since the exposure time difference is small, there is little influence on the curing characteristics of the resin material 49.

Furthermore, in this case, the time difference between the start of irradiation exposure between the laser beams 32a and 32b is approximately equal to the time it takes for the resin storage container 48 to move by the distance l mainly by the moving mechanism section 51,
From this point on, the supply of the liquid photocurable resin material 49 from the resin supply port 53 and the exposure and curing of the first and second laser beams 32a and 32b having different irradiation directions are simultaneously performed in parallel to the C direction and the D direction.

Eventually, as shown in FIG. 6, the resin supply port 53 reaches the other end of the container 48 and the first and second laser beams 32
When the exposure curing of the predetermined pattern by a and 32b is completed, the supply of the liquid photocurable resin material 31 is also stopped, and the sub-scanning of the resin container 48 is also stopped.

Next, as shown in FIG. 7, the resin storage container 48 is lowered by the moving mechanism 51 by the thickness of the resin material for which the liquid photocurable resin material 49 is supplied and exposed and cured.
The surface of the resin material of the next layer is exposed to fθ through the scanning reflector 45°46.
Level adjustment is performed so that the focal position of the lens 43 is achieved.

Thereafter, the resin container 48 is quickly returned to its original predetermined position as shown in FIG.

Immediately after the resin storage container 48 is returned, the steps explained in FIGS. 2 to 6 are repeated, and the exposed and cured resin layers are sequentially laminated to form a layered three-dimensional cured resin image using liquid photocurable resin. By removing the resin material 31 from the material 31 and washing away the liquid photocurable resin material 31 with, for example, a dilute alkaline cleaning solution, a three-dimensional model shape that displays desired three-dimensional stereoscopic information is efficiently formed in a relatively short time. becomes possible.

As described above, in this embodiment, the formation data signal of each three-dimensional shape is controlled in consideration of the difference in exposure start time between the first laser beam 32a and the second laser beam 32b that irradiate the photocurable resin material 49. By performing exposure scanning, a steep change in exposure energy distribution depending on the laser beam diameter is produced at the boundary between the cured and uncured areas not only in the main scanning direction and the sub-scanning direction but also in the depth direction of the resin material 49. A three-dimensional shape is easily formed in which the boundary area between the exposed hardened portion and the uncured portion of the photocurable resin material 49 does not change much with respect to changes in parameters such as the exposure energy threshold. be able to.

FIG. 9 is a schematic perspective view showing the structure of a second embodiment of the three-dimensional shape forming apparatus according to the present invention, and parts equivalent to those in FIG. 1 are given the same reference numerals.

This embodiment is different from the first embodiment shown in FIG. The light modulator 61 and the reflecting mirror 6
2. The laser beam 32 that passes through lenses 63 and 64 is deflected by a rotating polygon mirror 65, and further emitted from the fθ lens 67 based on the three-dimensional shape formation data signal, is split into two different directions by an optical splitter 68. The branched first and second laser beams 32a and 32b are fed into a photocurable resin material 49 into a resin container 48 as shown in FIG.
The irradiation is carried out in a superimposed manner at a predetermined exposure position, and the irradiation is cured by exposure.

According to the configuration of this embodiment, the time required for the resin storage container 48 to move by the distance l in the sub-scanning direction between the main scanning position of the first looser beam 32a and the elongated supply port 53 of the resin material supply section 52 is equivalent to The exposure start time difference between the second laser beam 32a and the second laser beam 32b is eliminated, the configuration of the laser optical system is simplified, and the same effects as in the embodiment shown in FIG. 1 can be obtained.

FIG. 11 is a schematic perspective view showing the structure of a third embodiment of the three-dimensional shape forming apparatus according to the present invention, and the same parts as in FIG. 9 are given the same reference numerals. □ The difference between this embodiment and the second embodiment shown in FIG. 9 is that fθ
The laser beam 32 emitted from the lens 67 based on the three-dimensional shape formation data signal is reflected by the scanning reflecting mirror 46, and split into two in different directions by the optical splitter 71 having a length corresponding to the scanning reflecting mirror 46. Then, the branched first and second laser beams 32a and 32b are further reflected by the secondary scanning reflecting mirror 72, respectively, and as shown in FIG. The mold resin material 49 is irradiated with light at a predetermined exposure position in a superimposed manner and cured by exposure.

Further, in this embodiment, in order to simplify the explanation, illustrations and explanations of the method of supplying the photocurable resin material 49 are omitted, but the method shown in FIGS. Not only the supply method shown in the second embodiment but also the supply method shown in the conventional example can be applied.

In the device structure of the present embodiment described above, FIGS.
Figure 1. The same effects as in the second embodiment can be obtained.

In each of the above embodiments, the laser beam from a single laser device is split into two by an optical splitter placed before or after the laser optical system. Although described, the present invention is not limited to this example. For example, two laser beams may be obtained by two laser devices without using an optical splitter.

〔Effect of the invention〕

As is clear from the above description, according to the three-dimensional shape forming apparatus according to the present invention, two laser beams are used to selectively irradiate and cure the liquid photocurable resin material. Since it is possible to superimpose irradiation on a predetermined exposure position of the resin material and perform exposure curing by predetermined scanning, the exposure energy distribution at the boundary between the cured part and the uncured part becomes steep, achieving the desired high precision and high quality. It has an excellent advantage of being able to efficiently and easily form a three-dimensional model shape that displays three-dimensional three-dimensional information.

[BRIEF DESCRIPTION OF THE DRAWINGS] FIG. 1 is a schematic perspective view showing a first embodiment of a three-dimensional shape forming apparatus according to the present invention. FIG. 2 is a partial cross-sectional diagram explaining the present invention in detail. Exposure energy distribution diagrams of the irradiated laser beam in the depth direction of the curable resin material, FIGS. 4 to 8 sequentially explain an example of the operation of forming a three-dimensional shape by the three-dimensional shape forming apparatus shown in FIG. 9 is a schematic configuration perspective view showing a second embodiment of the three-dimensional shape forming apparatus according to the present invention, and FIG. 10 is a three-dimensional shape forming apparatus according to FIG. 9 for forming a three-dimensional shape. 11 is a schematic configuration perspective view showing a third embodiment of the three-dimensional shape forming apparatus according to the present invention; FIG. 12 is a three-dimensional shape forming apparatus according to FIG. 11; FIGS. 13 to 18 are cross-sectional views of main parts for explaining an example of the operation of forming a three-dimensional shape by the apparatus; FIGS. 13 to 18 are cross-sectional views of main parts for explaining a conventional method of forming a three-dimensional shape; . In the figure, 31 is a laser device, 32 is a laser beam, 32a
is the second laser beam, 32b is the second laser beam, 33
, 68.71 is a light splitter, 34.35.62 is a reflector,
36° 37, 61 are optical modulators, 38 to 41 and 63.6
4 is a lens, 42 and 65 are rotating polygon mirrors, 43.44.6
7 is fθ lens, 45, 46.47.69.72a, 7
2b is a scanning reflecting mirror, 48 is a resin storage container, 49 is a liquid photocurable resin material, 50 is a support stand, 51 is a moving mechanism section, 5
Reference numeral 2 indicates a resin supply section, and reference numeral 53 indicates a resin material supply port. Fig. 1 Fig. 2 Fig. 3 Layering of Kijima gauze in L direction upper cl (mm) Fig. 4・35 Dimensions, Fig. 6
Fig. 7 Fig. 9 Fig. 10 Fig. 11 Fig. 12 Fig. 13 Fig. 14- Fig. 15 Fig. 16 Fig. 17

Claims (1)

[Claims] In an apparatus for selectively curing a liquid photocurable resin material supplied to a resin storage container by irradiating a beam with a laser optical system to selectively harden the photocurable resin material and forming a three-dimensional shape, the laser optical system The two laser beams are applied to the liquid photocurable resin material based on three-dimensional shape formation data,
A three-dimensional shape forming device characterized by superimposed irradiation from different directions.