JPS61116321A - Three-dimensional shape forming device - Google Patents

Abstract

PURPOSE:To simplify a device and to form a three-dimensional shape effectively for a short period by controlling the exposure energy of laser beams irradiated on a liquid light-curing resin material by a photomodulator. CONSTITUTION:A laser beam 22 radiated from a laser device 21 is modulated up to a prescribed light intensity by the photomodulator 24 on the basis of a three-dimensional shape information pattern signal stored in a signal control circuit 23, and then converted into a proper beam diameter through lenses 26, 27. The converted beam is polarized by a rotary polahedral mirror 28 controlled by a signal control circuit 23, scanned at a constant speed by an ftheta lens 29 and then irradiated on a liquid light-curing resin material 32 filling the inside of a resin storing vessel 31. In this case, a supporting board 33 mounting the vessel 31 is also moved on the basis of the three-dimensional shape information pattern signal, so that the resin is selectively exposed and cured also in the depth direction in addition to the surface of the resin material 32.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a three-dimensional model for displaying three-dimensional information such as a three-dimensional topographical map model using a liquid photocurable resin material and a laser beam irradiation means. The present invention relates to a shape forming apparatus, and in particular to a device configuration in which a three-dimensional shape can be easily formed by variably controlling the exposure energy of a laser beam irradiated onto a liquid photocurable resin material, and the device configuration is simplified.

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.

It is often used. These are, with the exception of holography,
All of these techniques include a procedure for converting three-dimensional information into two-dimensional information, and cannot necessarily be said to be 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, it is best to create a three-dimensional shape such as a model in order to intuitively grasp and understand three-dimensional information (in order to display it).

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 conventional forming methods, the photocurable resin material is supplied in stages using an overflow method, which complicates the supply mechanism and increases the supply time to the total forming process time. This problem accounts for most of the problems, and there is a desire to shorten the resin supply time.

[Conventional technology]

Conventionally, as a method of forming a model shape that displays three-dimensional stereoscopic information by using a photocurable resin material using a laser beam irradiation means, as shown in FIG. 7, 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, - the required photocurable resin material 4 is laser-irradiated with a first information pattern signal among cross-sectional information pattern signals obtained by dividing the model shape to be created into several slices in the height direction. Beam 5 or photocurable resin material 4 side x
, beam irradiation is performed while moving and scanning in the y direction, and the first cured resin layer 4a is selectively exposed and cured.

Next, as shown in FIG. 8, the lifting support 2 is lowered again by a predetermined distance, and the first cured resin layer 4 on the lifting support 2 is lowered again.
A new second layer of photocurable resin material 6 is supplied on top of a in the same manner as above, and the photocurable resin material 6 is similarly exposed to the laser beam 5 by the second information pattern signal as shown in FIG. is selectively exposed and cured to form a second cured resin layer 6.
form a.

Thereafter, in the same manner as shown in FIG. 10, 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 As shown in FIG. 11, the material 7 is irradiated with the laser beam 5 according to the third information pattern signal to selectively cure the material 7 by exposure to form a third cured resin layer 7a, and finally the liquid 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 by washing away the liquid photocurable resin material 3 with a dilute alkaline cleaning solution, a desired three-dimensional solid is created as shown in FIG. A model shape 8 for displaying information is being created.

[Problem that the invention seeks to solve]

However, the method of supplying the liquid photocurable resin material 3 in the above-mentioned forming method is such that the liquid photocurable resin material 3 is supplied onto the elevating support 2 that has been lowered by a certain amount, or onto the cured resin layer 4a or 6a that has already been formed on the elevating support 2. As shown in FIGS. 8 and 10, the liquid photocurable resin material 4 or 6 is supplied by the so-called overflow method, in which it flows naturally. Coupled with the relationship with the viscosity of the photocurable resin material 3, this requires a considerable amount of supply time.

Therefore, when forming a three-dimensional shape in a layered manner as described above, the total supply time of the liquid photocurable resin material 3 is - the number of layers times the resin material supply time for the essential resin material, and the total forming process time is There are disadvantages that greatly affect the

In addition, since the surface of the photocurable resin material, which is set in stages, becomes the focal point of the irradiation beam, considerable precision is required for the movable parts that move up and down the lifting support, and these drive mechanisms have the disadvantage of becoming complicated. there were.

[Means for solving problems]

The above problem occurs in an apparatus that selectively hardens a liquid photocurable resin material housed in a resin storage container by irradiating a beam with a laser optical system to form a three-dimensional shape. , the light modulation section consisting of the light modulator in the laser optical system is driven based on the shape data signal of the three-dimensional shape to be formed from the signal control circuit, and the exposure energy of the irradiation beam to the liquid photocurable resin material is controlled. This problem is solved by the three-dimensional shape forming apparatus according to the present invention, which is configured to variably control and change the exposed and cured layer thickness.

[Effect]

That is, when a laser optical system irradiates a liquid photocurable resin material housed in a resin storage container with a beam, the thickness of the liquid photocurable resin material to be photocured and the striking depth are determined by the irradiation light energy. The acousto-optic modulator in the laser optical system is driven based on the shape data signal of the three-dimensional shape, and the laser beam is selectively scanned with respect to the surface of the resin material, or the laser beam is In addition to moving the resin material side, the exposure energy of the irradiation beam to the liquid photocurable resin material can be variably controlled to partially change the thickness (depth) of the exposed cured layer of the resin material. By doing so, a desired three-dimensional shape can be easily created in a short time with a simple device configuration that does not require a mechanism for supplying the liquid photocurable resin material in stages.

〔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 an embodiment of a three-dimensional shape forming apparatus according to the present invention.

In the figure, 21 is a laser device that emits a laser beam 22, 23 is a signal control circuit, 24 is an optical modulator, 25 is a reflecting mirror, 26, 27 is a lens, 28 is a rotating polygon mirror, and 29 is a rotating polygon mirror 28. An fθ lens having a function of uniformly scanning the irradiation surface with the laser beam 22 to be scanned; 30 is a scanning reflecting mirror; 31 is a liquid photocurable resin material 3;
2, 33 is a support stand, and 34 is a moving mechanism for moving the support stand 33 in the direction of arrow A.

As the optical modulator 24, a modulator using an acousto-optic effect, an electro-optic effect, a magneto-optic effect, etc. can be applied. In this embodiment, an acousto-optic modulator is used to modulate the light intensity of the laser beam 22 using Bragg diffraction. As shown in the graph showing the relationship between the drive power and the diffraction efficiency of diffracted light, the diffraction efficiency can be controlled by controlling the drive power.

On the other hand, the depth of exposure curing of the liquid photocurable resin material 32 upon irradiation with the laser beam 22, that is, the cured layer thickness increases as the beam exposure energy Ee (light intensity) increases, as shown in FIG. . Therefore, from the characteristics of the optical modulator 24 and the photocured thickness characteristics of the resin material 32, the driving power characteristics of the optical modulator 24 to obtain the desired photocured thickness are obtained, and the characteristics shown in FIG. 4 are obtained. It will be done.

Therefore, based on the shape data signal of the three-dimensional shape to be formed as shown in the figure, for the resin material 32 portion whose photocuring thickness is XI, the driving power of the optical modulator 24 is set to Pl, and the photocuring thickness is also set to For the resin material 32 portion designated as X2, the driving power required to obtain a predetermined photocured thickness for each resin material 32 portion is determined in advance, such that the driving power of the optical modulator 24 is P2. These correspondence relationship data are stored in the signal control circuit 23 that drives and controls the optical modulator 24.

Further, the laser beam 22 intensity-modulated by the optical modulator 24 can be focused on the irradiation surface by the fθ lens 29, and the diameter of the laser beam at the focus can be made minute. Beam exposure energy Ee
Concentrated irradiation is possible.

Now, in order to apply the above-mentioned apparatus to form a desired three-dimensional model shape that displays three-dimensional stereoscopic information, the laser beam 22 emitted from the laser apparatus 21 as shown in FIG. The relationship data between the three-dimensional shape information pattern signal stored in the signal control circuit 23 in the modulator 24, that is, the photocured layer thickness data (X) shown in FIG. 5, and the light irradiation position data and the corresponding data shown in FIG. Modulation control is performed to a predetermined light intensity based on the relationship data between the driving power and the light irradiation time shown in , and the beam is converted to an appropriate beam diameter by lenses 26 and 27.

Next, the liquid photocurable mold is deflected by a rotating polygon mirror 28 which is also controlled by the signal control circuit 23, scanned at a constant speed by an fθ lens 29, and then filled into a resin container 31 by a scanning reflector 30. The irradiation is focused on the scanning line B on the surface of the resin material 32.

At this time, the support stand 3 on which the resin container 31 is placed
3, the movement mechanism section 34 is controlled based on the three-dimensional shape information pattern signal from the signal control circuit 23, and at the same time arrow A
In fact, as shown in FIG. 5, the resin material 32 is selectively exposed and cured not only on the surface but also in the depth direction.

Therefore, as described above, a three-dimensional cured resin image is formed in the liquid photocurable resin material 32 based on the curing characteristics of the commonly used resin material 32, the diffraction efficiency of the light modulator 24, three-dimensional shape formation data, etc. Ru.

This three-dimensional cured resin image is taken out from the liquid photocurable resin material 32 and the liquid photocurable resin material 32 is washed away with a dilute alkaline cleaning solution or the like, thereby creating a three-dimensional model that displays desired three-dimensional stereoscopic information. It becomes possible to form a shape efficiently in a short time.

〔Effect of the invention〕

As is clear from the above description, according to the three-dimensional shape forming apparatus according to the present invention, the exposure energy Be of the laser beam applied to the liquid photocurable resin material is controlled by the optical modulator using the acousto-optic effect or the like. By doing this, the thickness of the photocuring layer for the liquid photocurable resin material can be changed, so there is no need to perform multilayer curing as in the past, simplifying the device configuration, and creating the desired three-dimensional shape. The present invention has an excellent advantage in that a three-dimensional model shape, such as a three-dimensional topographic map model, for displaying information can be formed efficiently and easily in a relatively short time.

In addition, this device can also be used to form a three-dimensional shape with smooth unevenness, which is theoretically impossible to achieve using the conventional layer-curing method for forming a three-dimensional shape. By modulating the light intensity in an analog manner using the optical modulator, it is possible to easily achieve this, and it has practical effects.

[Brief explanation of drawings]

FIG. 1 is a schematic perspective view showing an embodiment of a three-dimensional shape forming apparatus according to the present invention, and FIG. FIG. 3 is a characteristic diagram showing an example of the relationship between the diffraction efficiency and the exposure energy of the laser beam modulated by the acousto-optic modulator and the photocured layer thickness for the resin material; The figure is a characteristic diagram showing an example of the relationship between the drive power of the acousto-optic modulator and the photocured layer thickness for the resin material. Figures 5 and 6 are the relationship between the drive power of the acousto-optic modulator and the three-dimensional shape formation data. Characteristic diagrams illustrating an example. FIGS. 7 to 12 are cross-sectional views of main parts for explaining a conventional method for forming a three-dimensional model shape. In the figure, 21 is a laser device, 22 is a laser beam, 23 is a signal control circuit, 24 is an optical modulator, 25 is a reflecting mirror, 26° and 27 are lenses, 2nd is a rotating polygon mirror, 29 is an fθ lens,
30 is a scanning reflecting mirror, 31 is a resin container, 32 is a liquid photocurable resin material, 33 is a support base, and 34 is a moving mechanism section. Figure 1 Figure 2! 21 □ Ji'tftl home? (w) Figure 3 - No. tx channel 't' - Ee (mVcm") @4rM → LJ? Ibi 1 layer 7g (m? F+) Figure 5 Figure 6 → , Snore Kano (1) Figure 7 Figure 8 Figure 9 Figure 11 Figure 10

Claims (1)

[Claims] In an apparatus for selectively curing a liquid photocurable resin material housed in a resin storage container by irradiating a beam with a laser optical system to selectively harden the photocurable resin material, the laser optical system described above The light modulation unit is driven based on the shape data signal of the three-dimensional shape to be formed from the signal control circuit, and the exposure energy of the irradiation beam to the liquid photocurable resin material is variably controlled, and the exposed and cured layer thickness is controlled. A three-dimensional shape forming device characterized by being configured to change.