KR20000018892A - Method and apparatus for fabricating three-dimensional optical model using liquid crystal display panel and method the same - Google Patents

Abstract

PURPOSE: A device for fabricating three dimensional optical model is provided to reduce mask production time to manufacture by utilizing a negative mask using an LCD(Liquid Crystal Display) panel, and easily form and remove the negative mask. CONSTITUTION: A method for fabricating an optical model comprises the steps of forming a photo plastic resin layer on a platform, forming a negative mask pattern on a liquid crystal display panel, and irradiating light to the photo plastic hardened resin layer through the negative mask pattern of the LCD(Liquid Crystal Display) panel. The optical model is formed by repeating the above steps.

Description

3D optical sculpture manufacturing method and manufacturing apparatus using liquid crystal panel

The present invention relates to a three-dimensional light shaping method, and more particularly, to a three-dimensional light shaping method using a liquid crystal panel and an ultraviolet lamp.

In general, when developing a new product, it is necessary to verify the design or assemblability of the product to be developed, and for this, a prototype is produced. Industries, especially home electronics companies, are using Rapid Prototyping to quickly build models. Using this rapid manufacturing method, it is possible to produce a three-dimensional model by stacking cross sections of a desired thickness without cutting.

For example, in the three-dimensional steerolithography developed by 3D Systems, Inc., a thin layer of photocurable resin is applied onto a platform, and then irradiated with an ultraviolet laser beam to cure a desired cross section. The series of processes of applying and curing the photocurable resin again on the phase is repeated. In this case, the path of the beam is provided via CAD data.

In a similar way, a technology developed and commercialized by Israel's Cubital Co., Ltd. is a Solid Ground Curing (SGC) process for curing a photocurable resin with an ultraviolet lamp. This technique uses UV light through a negative mask with a light shielding film that must be transparent to allow light to pass through the part to cure the photocurable resin and to prevent light to pass through to the part that should not be cured. There is an advantage that the desired cross section can be cured at once. However, at this time, in order to harden the predetermined | prescribed area | region of photocurable resin, the negative mask as mentioned above is essential.

FIG. 1 sequentially shows a conventional method for manufacturing a negative mask and an SGC process for manufacturing a three-dimensional model using the mask. As shown in FIG. 1, the SGC process is configured to include the mask fabrication cycle described in five steps and the model formation cycle described in six steps.

First, in the mask fabrication cycle, pattern data for negative mask fabrication is prepared in step (a). Then, in step (b), the portion under the glass plate 20 (or the film for the overhead projector) is partially electrostatic charged in accordance with the pattern. Then, in step (c), the toner is deposited on the electrostatically charged portion of the glass plate 20 to obtain a mask in which a pattern is formed. Then, in step (d), the curable resin of the irradiated portion is cured by irradiating ultraviolet rays to the curable resin using the portion to which the toner is deposited as a mask. Finally, in step (e), the toner of the glass plate 20 is removed for the next mask fabrication. In this way, the negative mask can be repeatedly produced by repeating steps (a) to (e).

Next, in the model formation cycle, a photopolymer layer is formed on the mold 30 prepared in step 31. Then, in step 32, light is selectively irradiated to the photopolymer layer formed by performing the above-described step (d). A cavity region is formed in the photopolymer layer by removing the unirradiated portion of the photopolymer layer in step 33. The wax is then filled into the cavity in step 34. The wax is then cooled in step 35 to cure. Finally, in step 36, the hardened wax is polished through milling, or the thickness is adjusted. As a result, a three-dimensional model can be obtained by repeating these steps 31 to 36.

As described above, according to the conventional method of producing a three-dimensional model using a corresponding number of negative masks to be used for repetitive tasks, which may be hundreds or thousands or more depending on the shape of the model, and using the same, The process of manufacturing the necessary negative mask is not only cumbersome but also requires a large number of mechanical devices. In addition, there is a problem in that it takes a long time to produce the entire three-dimensional model because the additional work time for generating the negative mask is consumed in addition to the resin curing time.

An object of the present invention is to solve the problems described above, to provide a three-dimensional model manufacturing apparatus shortened the production time using a simple equipment, in particular a liquid crystal panel (LCD panel) used for display By creating a negative mask, a three-dimensional model manufacturing apparatus can be manufactured at low manufacturing cost and low equipment maintenance cost.

Another object of the present invention is to provide a method for producing a three-dimensional model using the apparatus of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a view sequentially showing a conventional method for manufacturing a negative mask and an SGC process for manufacturing a three-dimensional model using the mask.

2 illustrates an apparatus for manufacturing a three-dimensional model according to a preferred embodiment of the present invention.

3A to 3E are steps illustrating a method of manufacturing a 3D model using the 3D model manufacturing apparatus shown in FIG. 2.

<Explanation of symbols for main parts of the drawings>

1: signal processor

2: liquid crystal panel

3: platform

4: light source

5: resin container

6: photocurable resin

7: recorder

The three-dimensional model manufacturing apparatus of the present invention for achieving the above object is a liquid crystal panel for generating a negative mask, a signal processor for controlling the liquid crystal panel, a platform on which a photocurable resin is applied, and a photocurable on the platform through the liquid crystal panel The light source used for irradiating light to resin is included.

Preferably, the platform is provided in a resin container in which the photocurable resin is stored, and when the photocurable resin is applied to the upper surface of the platform with a predetermined thickness, a coater is further provided to evenly control the surface of the applied photocurable resin. have.

Method for manufacturing a three-dimensional model using the three-dimensional model manufacturing apparatus of the present invention, the step of moving the platform so that the length from the resin surface to the upper surface of the platform in a resin container filled with photocurable resin to have a predetermined depth, Forming a negative mask on the liquid crystal panel, irradiating light to the photocurable resin disposed on the upper surface of the platform to a predetermined depth through the liquid crystal panel in which the negative mask is formed using a light source, and the photocurable resin in the irradiated region Curing.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

2 shows an apparatus for manufacturing a three-dimensional model according to a preferred embodiment of the present invention. 3A to 3E illustrate step by step a method of manufacturing a model using the three-dimensional model manufacturing apparatus shown in FIG.

The 3D model manufacturing apparatus which concerns on this invention is comprised including the liquid crystal panel 2, the signal processor 1, the platform 3, and the light source 4 roughly. The model manufacturing apparatus further includes a resin container 5 filled with a recorder 7 and a photocurable resin 6 for leveling the resin surface.

Referring to the operation of the apparatus of the present invention, first, the height of the platform 3 so that the thickness from the surface of the resin 6 in the resin container 5 filled with the photocurable resin 6 to the upper surface of the platform 3 becomes a predetermined thickness. By varying, the flowable photocurable resin 6 flows to the upper surface of the platform 3, and eventually the photocurable resin corresponding to the predetermined thickness described above covers the upper surface of the platform 3. Then, the desired negative mask pattern is transmitted using the signal processor 1 to form the liquid crystal panel 2. And after irradiating the photocurable resin 6 of the upper surface of the platform 3 through the liquid crystal panel 2 in which the pattern was displayed using the light source 4, the photocurable resin 6 'of the irradiated area | region is hardened. Thereafter, the platform 3 is lowered by a predetermined height, and the above-described method is repeated to produce a three-dimensional shape that is a continuous shape of the cured resin.

Next, a preferred embodiment of the present invention will be described in detail with reference to FIGS. 3A to 3E.

As shown in FIG. 3A, the signal processor 1 (shown in FIG. 2) controls to use the liquid crystal panel 2 as a negative mask by generating and transmitting a desired negative mask pattern to the liquid crystal panel 2. As the following means, a personal computer (PC) can also be used. Using such a personal computer, a desired pattern can be generated in software, and a negative mask can be obtained by simply displaying the generated pattern on a liquid crystal panel.

The liquid crystal panel 2 for the negative mask thus produced was placed on an overhead projector and used a panel having a structure similar to that of a conventional liquid crystal panel used for presentation. A liquid crystal panel made of absorbing material was used. Since light can be selectively passed depending on the pattern of the liquid crystal panel used, the function as a normal mask can be realized.

The negative mask used in the preferred embodiment of the present invention is a mask in which the rectangular pattern 10 is formed, and is divided into a rectangular pattern region for transmitting light and a pattern peripheral region 11 for blocking light.

In this way, while the liquid crystal panel 2 is formed as a negative mask through the signal processor 1, when the platform 3 installed in the resin barrel 5 containing the photocurable resin 6 is driven downward, Resin 6 flows to the upper surface of the platform, resulting in a coated state. In other words, the formation of the negative mask and the driving of the platform 3 are performed independently, and are preferably performed simultaneously. At this time, the platform 3 is driven so that the thickness of the applied resin 6 becomes a desired thickness, about 0.2 mm. The platform 3 is equipped with a linear drive table so that the platform 3 is driven vertically. Since the positioning degree according to the vertical movement of the platform 3 is operated with a characteristic of, for example, ± 0.01 mm, the thickness of the photocurable resin 6 applied to the upper surface of the platform can be adjusted. The thickness of the photocurable resin irradiated once is determined by the size and output of the light source 4, the size of the liquid crystal panel 2, and the like. In a preferred embodiment, the width of the resin container is about 300 to 400 mm, and the thickness of the resin layer is about 0.1 to 0.2 mm. After laminating one layer, the recorder 7 is used to accurately match the thickness.

Then, as shown in FIG. 3B, when the negative mask is prepared and the thickness control of the photocurable resin for irradiation is completed, the light source 4 is irradiated. The light source 4 used is an ultraviolet lamp having a wavelength of 325-350 nm and an output of about 1 kW. Of course, the wavelength of a lamp may be 400-500 nm according to the kind of photocurable resin to be used. The higher the output, the less time the resin cures in the irradiated area. Of course, in addition to the case where the irradiation area of the light source 4 is smaller than the mask pattern, a light source 4 driver capable of irradiating with varying the position of the light source 4 is further provided (not shown). If such a light source 4 driver is provided, the light source can be operated as if the document is being scanned, thereby solving some of the problem that the intensity of the light source in the irradiated area is not uniform.

At this time, as the photocurable resin 6, conventional resin types such as epoxy type and acrylic type can be used. By the way, epoxy type resin has the advantage of high curing rate and low shrinkage rate. In particular, a preferred embodiment of the present invention used a resin sensitive to ultraviolet light.

When irradiated with the light source 4 in this way, the photocurable resin of the irradiated area | region 6 'hardens and becomes solid.

Then, as shown in FIG. 3C, the platform 3 is driven downward to form the photocurable resin 6 to a thickness of about 0.2 mm on the solidified region 6 ′ in the preceding step.

Then, as shown in FIG. 3D, a recorder 7 is provided to even the surface of the photocurable resin applied by flowing on the upper surface of the platform. The role of the recorder 7 functions to evenly adjust the thickness of the resin layer applied to the upper surface of the platform while making the surface of the resin layer evenly described above. In order to realize such a function, the recorder 7 used in the preferred embodiment of the present invention used an example of attaching rubber used for glass wipers to an aluminum iron plate. Of course, as shown in 3a, a negative mask pattern provided from the signal processor 1 is formed in the liquid crystal panel 2.

As shown in FIG. 3E, the irradiated region 6 ″ is cured by irradiating the light source 4.

In this way, by repeating the process shown in FIGS. 3A-3E, a three-dimensional model, such as a rectangular parallelepiped obtained in the case of repeatedly using a negative mask of one rectangular pattern as in the embodiment of the present invention, is repeated. Can be obtained.

Of course, the process shown in Figures 3a to 3e can be operated to be automatically performed by appropriately adjusting the processing time for each step, it is possible to manufacture a three-dimensional model in a simple and quick method.

As described above, according to the preferred embodiment of the present invention, in the conventional SGC method, the negative mask using the liquid crystal panel is different from the time required to use the toner layer patterned on the glass (or film) and to remove the used toner. The mask manufacturing time is considerably shortened, and as a result, the three-dimensional model fabrication step and the manufacturing equipment are also simplified. In addition, unlike the conventional mask, since the image processed by software is used as a pattern, the negative mask used in the embodiment has a feature that it is very easy to generate and erase.

Thus far, the present invention has been described by way of example with reference to the preferred embodiments, it will be apparent to those skilled in the art that various changes to the invention can be made without departing from the technical scope and spirit of the invention. I understand that it's done. It is, therefore, to be construed that such changes are included within the scope of the invention as defined in the appended claims.

Claims (11)

In the optical sculpture manufacturing apparatus for irradiating light to a photoreactive material, Light Source, A mask comprising a material of varying state for selectively transmitting the light source, and A signal processor for providing a signal to the mask to form a negative pattern in the mask Optical sculpture manufacturing apparatus comprising a. The apparatus of claim 1, wherein the light source is ultraviolet light or visible light. The apparatus of claim 1, wherein the material is a photocurable liquid crystal. The apparatus of claim 1, wherein the mask is a liquid crystal panel. The apparatus of claim 1, wherein the signal processor is a personal computer. The apparatus of claim 1, further comprising a platform for providing the photoreactive material at a position to which the light source is irradiated. The apparatus of claim 1, further comprising a recoater for leveling the surface of the photoreactive material. A first step of forming a photocurable resin layer on the platform, A second step of forming a negative mask pattern on the liquid crystal panel, and A third step of irradiating light to the photocurable resin layer through a negative mask pattern of the liquid crystal panel Optical sculpture manufacturing method comprising a. The method of claim 8, wherein the first step is performed by vertically driving the platform located in the resin container containing the photocurable resin. The method of claim 8, wherein the third step cures the photocurable resin into a pattern corresponding to a negative mask pattern of the liquid crystal panel. The method of claim 8, wherein the three-dimensional sculpture is formed by continuously repeating the first to third steps.