JPH03281329A - Optical three-dimensional shaping - Google Patents

Abstract

PURPOSE:To shape in a short time, highly-accurately and inexpensively a three- dimensional form without making an optical mask into a large size, by a method wherein the mask is scanned on cured resin in a monoaxial direction along with a light source and an optical transmission part of an optical mask is changed continuously by corresponding to horizontal sectional forms each. CONSTITUTION:An optical mask 3 such as a liquid crystal shutter plate whose optical transmission part is changed electrically by corresponding to a horizontal sectional form of a three-dimentional object 7 which is desirous to obtain is installed on this side of photosetting resin 2. Then moving scanning of the optical mask 3 is performed on the surface of liquid setting resin 2 integrally with a light source in a monoaxial or biaxial direction by an XY stage driver 11. The optical transmission part of the optical mask 3 is changed electrically in accordance with the scanning by corresponding to the horizontal sectional form by a driver 6 and a layer is thinned in order by size of an extent of the optical mask.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a three-dimensional modeling method in which a three-dimensional three-dimensional shape is formed by exposing and curing a liquid cured resin by irradiating it with light.

(B) Conventional technology Conventional optical three-dimensional modeling methods include a method in which three-dimensional modeling is performed by sequentially exposing and curing each cross-section using an optical mask as an application of semiconductor phosphorography technology, and a method in which three-dimensional modeling is performed by repeatedly exposing and curing each cross section sequentially. There is a method of performing three-dimensional modeling by scanning the resin surface along each cross-sectional shape and selectively curing the resin.

The method using an optical mask is based on the journal of the Institute of Electronics and Communication Engineers (19
81.4vo1. J64-CNo, 4P-237~
) is proposed in the paper published in .

This involves first irradiating extremely shallow liquid photocurable resin with light from above or below, and then placing an optical mask in front of the photocurable resin with a light-transmitting part corresponding to the horizontal cross-sectional shape of the three-dimensional object to be obtained. By this irradiation, a thin-layer cured part with a desired cross-sectional shape is obtained, and for the continuous horizontal cross-sectional shape, the depth of the photocuring resin is increased little by little, and the optical mask is sequentially replaced and light irradiation is repeated to obtain the desired shape. This is to obtain a three-dimensional object. However, with this method, it is necessary to manufacture an optical mask for each horizontal cross-sectional shape of the three-dimensional object to be obtained, which is characterized by time and effort. As a result, a large number of optical masks are required, which increases manufacturing time and costs.

On the other hand, the method of scanning light energy is
As disclosed in Japanese Patent Publication No. 247515 (Japanese Patent Publication No. 63-40650), a liquid photocurable resin is housed in a container, and the point of application of light energy can be moved relative to the container in three dimensions. A light irradiation means is provided, and the point of application of the light energy by the light irradiation means is first relatively moved in the horizontal direction while selectively irradiating the liquid photocurable resin with light energy to form a horizontal cured portion, Next, after slightly relatively moving the point of application in the vertical direction, or gradually moving it relative to each other and moving it relatively in the horizontal direction in the same manner as above, the cured portion is laminated, and by repeating this process, a desired three-dimensional object is modeled. It is something. However, in this method, the light irradiation means or the container is operated to move the point of action of the light niobium, and the liquid photocurable resin at the point of action is sequentially cured, so it is not possible to create a model in a short time. There is a problem in that it is not particularly suitable for modeling large three-dimensional objects.

In addition, as an idea to solve the above problem, when irradiating the liquid photocurable resin in the container with exposing light from above or below, the light transmitting part is adjusted according to the horizontal cross-sectional shape of the three-dimensional object to be obtained. An optical mask such as an electrically variable liquid crystal shutter is placed in front of the photocuring resin, and by this irradiation, a thin cured portion with a desired cross-sectional shape is obtained. The depth of the photocurable resin is gradually increased so that a thin liquid photocurable resin can be supplied between the light transmitting part and the electrically variable optical mask, and the light transmitting/receiving part of the optical mask such as the liquid crystal shutter is A method has been devised in which a liquid crystal shutter is used as an optical mask to obtain a desired three-dimensional shape by electrically changing the shape while matching the horizontal cross-sectional shape data and repeating light irradiation (see Japanese Patent Application No. 1-280261). . However, with this method, the size of the stereolithographic object is limited by the size of the liquid crystal shutter, and if a large three-dimensional object is to be modeled, the liquid crystal shutter must also be made large to match, resulting in an increase in the size of the equipment. There are also problems in the production of large liquid crystal shutters. To solve this problem, it is possible to install a lens between the liquid crystal shutter and the liquid photocuring resin, and project the image of the light transmitting part of the liquid crystal shutter onto the surface of the liquid photocuring resin (enlarged projection and photocuring it, but it is possible to reduce the modeling accuracy. There is a problem that the modeling time becomes longer due to the reduction in the amount of light and the amount of light.

(c) Problems to be Solved by the Invention In view of these points, the present invention is capable of forming a three-dimensional object in a short time without manufacturing an optical mask for each horizontal cross-sectional shape of the three-dimensional object and without moving the point of application of light energy. It is intended to be shaped.

(d) Means for Solving the Problems In the present invention, an optical mask such as a liquid crystal shutter plate whose light transmitting portion electrically changes depending on the horizontal cross-sectional shape of the three-dimensional object to be obtained is placed in front of the photocuring resin. The optical mask is moved and scanned integrally with the light source in one or two axial directions on the surface of the liquid photocurable resin, and the light transmitting part of the optical mask is moved in accordance with the scanning according to the horizontal cross-sectional shape. A thin layer cured portion having a desired cross-sectional shape is obtained by electrically changing the thickness of the thin layer and sequentially curing the thin layer in the size of an optical mask.

(E) Function Since the present invention uses the above-mentioned means, it does not require the trouble of manufacturing an optical mask for each horizontal cross-sectional shape. It is possible to fabricate large-sized three-dimensional shapes at low cost.

(f) Example Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an example of an apparatus for carrying out the method of the invention. A suitable amount of liquid photocurable resin 2 is stored in a resin storage container 1, and a liquid crystal shutter plate 3 that serves as an optical mask is placed on the surface of the liquid photocurable resin 2, and the liquid photocurable resin 2 is placed above the liquid crystal shutter plate 3. A light source 4 that emits a curable wavelength is installed, and the liquid crystal shutter plate 3 and the light source 4 are configured so that they can two-dimensionally scan the surface of the liquid photocurable resin 2 together by an XY stage 9. In this case, the size of the resin container 1 is larger than the size of the liquid crystal shutter plate 3. First, the lifting stage 5, which can move up and down within the liquid photocurable resin 2, is lowered from the surface of the liquid photocurable resin 2 by a thickness that can be cured in one exposure time. The liquid crystal shutter plate 3 is operated by the controller 6 so as to transmit light through a portion of a desired three-dimensional horizontal cross-sectional shape and block light from other portions.
The horizontal cross-sectional shape of the first layer is photocured by the thickness on the lifting stage 5. Next, the lifting stage 5 is moved one more time.
The controller 6 is operated so that the light transmitting part and the light blocking part of the liquid crystal shutter plate 3 change according to the horizontal cross-sectional shape of the second layer.
Photocure the second layer. By repeating the same process, a desired three-dimensional three-dimensional object 7 can be easily obtained by stacking many cured resin layers in a short time. When the horizontal cross-sectional shape of the desired three-dimensional object is larger than the exposure range of the liquid crystal shutter plate 3, which is an optical mask, the liquid crystal shutter plate 3 is integrated with the light source 4, and the surface of the liquid photocuring resin 2 is exposed by the XY stage 9. By scanning dimensionally, the liquid crystal shutter plate 3 is partially sequentially photo-cured according to the horizontal cross-sectional shape to form a horizontal cross-sectional shape of one layer.
An example of a procedure for forming a horizontal cross-sectional shape by scanning is shown below. Figure 2a shows the resin container 1 viewed from above.
The liquid crystal shutter plate 3 (shaded area) and the light source 4 (omitted in FIG. 2) are located at the upper left. The dashed line is the desired horizontal cross-sectional shape. First, while exposing and curing the diagonally shaded area on the left side, move the liquid crystal shutter plate 3 in the direction of the arrow using the XY stage 9.
and move the light source 4 (Fig. 2b). At this time, when the light transmitting part of the liquid crystal shutter plate 3 is exposed by changing the light transmission part of the liquid crystal shutter plate 3 continuously according to the horizontal cross-sectional shape as the liquid crystal shutter plate 3 is moved, the liquid crystal shutter plate 3 and the light source 4 are moved at a constant speed without stopping during scanning. Movement becomes possible. LCD shunter board 3
When the light source 4 is scanned as shown in FIG. 2C to F, the photocured horizontal cross-sectional shape shown by the solid line finally becomes as shown by the solid line in FIG. 2F. Then, the desired horizontal cross-sectional shape is photocured, and a three-dimensional three-dimensional object 7 is formed.

By laminating photocurable layers in this procedure, it is possible to create large three-dimensional objects.

This three-dimensional three-dimensional object is designed by the CAD device 8 and is converted into two-dimensional cross-sectional shape data for each horizontal section, and each data is sent to the controller 10. The controller 10 sends data to the liquid crystal shutter driver 6 and the
The position and speed of the Y stage 9 are controlled simultaneously. The liquid crystal shutter driver 6 corresponds to a cross-sectional portion of a portion of each liquid crystal shutter two-dimensionally arranged on the liquid crystal shutter plate 3 by applying technology used in displays, etc. The operation of the liquid crystal shutter plate 3 is controlled so that the portions transmit light, and the portions that do not correspond to the other cross-sectional shapes block light. Note that the distance between the liquid crystal shutter plate 3 and the surface of the liquid photocuring resin 2 is desirably as small as possible in consideration of light diffusion. Furthermore, in order to eliminate the influence of light diffusion, a method of preventing light diffusion by providing a lens array or the like between the liquid crystal shunter plate 3 and the surface of the liquid crystal resin photocuring resin 2 may be considered.

(G) Effects of the Invention According to the optical three-dimensional modeling method of the present invention, two masks are scanned over a cured resin together with a light source in one or two axial directions, and light transmission of the optical masks is performed according to each horizontal cross-sectional shape. Since the area changes continuously, it is possible to continuously perform exposure using a surface light source without having to create an optical mask for each horizontal cross-sectional shape and replace it each time, making it possible to print large three-dimensional shapes. Even if the optical mask is not large-sized, it can be used in a short time, with high precision, and at low cost.
It is possible to create three-dimensional shapes.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram of a three-dimensional modeling apparatus for implementing the optical three-dimensional modeling method according to the present invention, and FIGS. 2 a to f are explanatory diagrams showing the optical three-dimensional modeling method according to the present invention in the order of steps. It is. (1)...container, (2)...photocuring resin, (3)...
...Liquid crystal shutter plate, (4)...Light source, (5)...
・Elevating stage, (61 (111...driver, (7
)...Three-dimensional object, (9)...XY stage, (1
0)...Controller. Ryo Ganjin Sanyo Electric Co., Ltd.

Claims (1)

[Claims] 1) A liquid photocurable resin material is placed in a resin storage container, and the photocurable resin is irradiated with light through an exposure mask with a horizontal cross section to selectively cure the photocurable resin and form a three-dimensional shape. A method for optical three-dimensional modeling, characterized in that the mask is scanned over the photocuring resin together with the light source in one or two axial directions, and the horizontal cross-sectional shape of the mask is continuously changed. Method.