JP2004216730A - Optical three-dimensional shaping method and apparatus therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical three-dimensional shaping method for producing a three-dimensional shaped article having high shaping precision and dimensional precision at a high shaping speed with good optical energy efficiency and good productivity by a simple and inexpensive apparatus, and an apparatus for the method. <P>SOLUTION: In the optical three-dimensional shaping method and the apparatus for the method, light emitted from a light source is separated into two polarized lights whose vibration directions cross each other at right angles by the polarized light splitting surface of a polarized light splitting element. One separated polarized light is let pass through the polarized light splitting element to be turned toward a drawing mask. The other separated polarized light is reflected by the polarized light splitting surface and re-reflected, scattered and/or absorbed so as not to pass through the polarized light splitting element. One polarized light which is passed through the polarized light splitting element is applied to a shaping surface of a photo-setting resin composition through the drawing mask having a liquid crystal shutter to form a photo-set resin layer having a prescribed profile pattern corresponding to the mask image of the drawing mask. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an optical three-dimensional modeling method, an optical three-dimensional modeling device, and an optical device. More specifically, the present invention uses a photocurable resin composition to form various three-dimensional objects using a simple and inexpensive device, with high light energy efficiency, high modeling accuracy, and rapid modeling. The present invention relates to an optical three-dimensional modeling method that can be manufactured at high speed and with high productivity, an optical three-dimensional modeling apparatus therefor, and an optical device that can be effectively used for them.
[0002]
[Prior art]
2. Description of the Related Art In recent years, an optical shaping method and apparatus for manufacturing a three-dimensional structure by curing a photocurable resin based on data input to three-dimensional CAD has been put to practical use. This stereolithography technology includes models for verifying the external design during the design process, models for checking the functionality of parts, resin models for producing molds, and base models for producing molds. Such a complicated three-dimensional object can be easily formed.
[0003]
In manufacturing a molded article by an optical molding method, a method using a molding bath is widely used, and as a procedure, a liquid photocurable resin is put in a molding bath, and a desired pattern is obtained on a liquid surface. A spot-shaped ultraviolet laser beam controlled by a computer is selectively irradiated to light-cur to a predetermined thickness to form a cured resin layer, and the cured resin layer is moved downward in a molding bath to form a molding bath. The photo-curable resin liquid in the above is caused to flow on the cured resin layer to form a layer of the photo-curable resin liquid, and the photo-curable resin liquid layer is irradiated with spot-shaped ultraviolet laser light to form the cured resin layer. A method of forming and repeating the above steps until a three-dimensional structure having a predetermined shape and dimensions is obtained is widely used.
[0004]
However, in the case of the above-described conventional method using spot-shaped ultraviolet laser light, a so-called spot-shaped laser light is moved while irradiating the surface of the photo-curable resin to form a planar light-cured pattern. Because of the stippling method, there is a problem that a long time is required for modeling and productivity is low. Moreover, an ultraviolet laser device used as a light source is extremely expensive, which makes this type of three-dimensional optical device expensive.
[0005]
In order to solve the above-mentioned problems in the prior art using the spot-shaped laser light and to improve the molding speed, instead of the spot-shaped laser light, a planar mask is used, and through the planar mask, An optical molding method has been developed in which light corresponding to a cross-sectional shape pattern to be molded is irradiated in a plane onto a molding surface made of a photocurable resin, and the irradiated portion of the photocurable resin is cured in a plane. As such an optical molding technique using a planar mask, there is known a method using a drawing mask including a liquid crystal shutter capable of transmitting and blocking light in a minute dot area (for example, see Patent Documents 1 to 4).
[0006]
As is well known, light oscillates with a number of vibrating surfaces. However, light is phenomenally represented as a vibrating wave (polarized light) (P wave) having a vibrating surface in the horizontal direction, as shown in FIG. Vibration waves (polarized light) (S waves) having a vibration surface in the vertical direction can be separated.
In the conventional optical three-dimensional printing apparatus described in Patent Documents 1 to 4, etc., a liquid crystal shutter similar to that used in a liquid crystal display device or the like is used as a drawing mask including the liquid crystal shutter. Two polarizing films (polarizing plates) are arranged on both sides of the entrance and exit sides of the liquid crystal shutter with their polarization directions orthogonal to each other. In such a liquid crystal shutter, light emitted from a light source or the like is polarized in the same polarization direction as that of the polarizing film by a polarizing film disposed on the entrance side. That is, of the P-waves or S-waves described above, only one of P- and S-waves having a vibration plane in the same direction as the polarization direction of the entrance-side polarizing film is transmitted to the liquid crystal through the entrance-side polarizing film. The polarized light that has been guided into the liquid crystal is subjected to a microswitching action (on / off action) by the cooperation of the alignment state of the liquid crystal caused by the presence or absence and strength of the voltage and the polarization direction of the polarizing film disposed on the exit side. It passes through a shutter or is stopped by a liquid crystal shutter, whereby a predetermined planar mask image is formed, and light of a predetermined shape pattern corresponding to the planar mask image is applied to a molding surface made of a photocurable resin. Thus, a predetermined photocured cross-sectional shape pattern is formed on the modeling surface.
[0007]
However, when a drawing mask composed of a liquid crystal shutter used in the prior art such as Patent Documents 1 to 4 is used, the amount of light emitted from a light source or the like is determined by a polarizing film disposed on the liquid crystal entrance side. Is greatly reduced. That is, at the time when the light passed through the polarizing film on the entrance side, the amount of light was reduced to about 10 to 30% before the light was passed, and the light energy efficiency was extremely low. In particular, ultraviolet light generally used in optical three-dimensional modeling has a short wavelength, so it is easily absorbed by the polarizing film, and accordingly the amount of light is significantly reduced, and after passing through the polarizing film arranged on the entrance side of the liquid crystal shutter, At present, the amount of light is reduced to about 10% before passing.
Therefore, in the case of the conventional techniques described in Patent Documents 1 to 4, etc., the intensity of light applied to the molding surface made of the photocurable resin is insufficient, and it takes time to cure the photocurable resin, and There have been problems such as a decrease in speed, insufficient curing, and a decrease in modeling accuracy. In such a conventional technique using a drawing mask composed of a liquid crystal shutter, in order to avoid problems such as a decrease in modeling accuracy and a modeling speed, high-energy light must be irradiated. It is necessary to use an expensive light source capable of irradiation, and there is a problem in energy efficiency, cost, and the like.
[0008]
On the other hand, although it is not an optical three-dimensional modeling device, in an optical device such as a projector using a liquid crystal shutter, the purpose is to prevent the above-mentioned decrease in light amount caused by disposing a polarizing film on the entrance side of the liquid crystal shutter. Instead of disposing a polarizing film (polarizing plate) on the entrance side of the liquid crystal, a lens array, a polarization separating element (PS separating film), a half-wave phase delay element (1 / 2λ wave plate), etc. From the lens is condensed using a lens array, and the condensed light is condensed using a PS separation film into two polarized lights whose vibration directions are orthogonal to each other (a P wave having an XY plane as a vibration plane and an XZ plane). Of the polarized light (P-wave or S-wave) separated through the PS separation film, and the other is reflected by the reflection film, and the two polarized lights (P-wave or S-wave) are reflected by the reflection film. One of polarized light The polarization direction is rotated by 90 ° by a 波長 wavelength phase delay element (１ ／ λ wavelength plate) so that the oscillation directions (polarization directions) of the two polarized lights are aligned to be supplied to the liquid crystal shutter. An optical device as shown in FIG. 6 is known.
[0009]
In addition, a polarization separation element using a diffraction grating, a first lens array, a phase difference plate (wavelength phase delay element), a second lens array, and the like are sequentially arranged on the entrance side (upstream side) of the liquid crystal switch. A projection type projection device (for example, see Patent Literature 5) in which the light from the light source is arranged in the same direction and supplied to the liquid crystal switch, and the light from the light source is condensed using a lens array; It is separated into ordinary light and extraordinary light through a birefringent crystal such as calcite, and one of the ordinary light and extraordinary light is rotated 90 ° by a half-wavelength phase delay element to make the vibration directions of both lights the same. An optical device (see, for example, claims in Patent Document 6) that aligns and supplies a liquid crystal light valve (liquid crystal shutter) is known.
[0010]
Further, as shown in FIG. 7, for example, a polarization separation surface and a reflection surface are alternately arranged obliquely in a transparent body made of glass or the like, and a shielding plate is arranged on the light incident side of the reflection surface portion. There is known an optical device for forming a single polarized light in which a half-wavelength phase delay element is arranged on one of the light emitting side of a portion and a reflection surface portion (for example, paragraph 0006 of Patent Document 6 and FIG. 9). See).
In this optical device, incident light (mixed wave of P-wave and S-wave) is separated into two polarized lights (P-wave and S-wave) whose vibration directions are orthogonal to each other by a polarization splitting surface, and separated into the two. One of the polarized lights (P wave or S wave) (P wave in FIG. 7) passes through the polarization separation surface, and the other polarization (S wave in FIG. 7) is reflected by the polarization separation surface. Further, the light is reflected by the reflecting surface and its traveling direction is aligned with the same direction as the one polarized light (P wave in FIG. 7) that has passed through the polarized light separating surface. Either one of the two polarized lights (P wave or S wave) (P wave in FIG. 7) whose traveling directions are aligned is a half-wavelength phase delay element (1/2) disposed on the traveling path. The light is rotated by 90 ° by a 2λ wavelength plate, and its polarization direction (oscillation direction) is changed, and a single polarization (S-wave in FIG. 7) having the same oscillation direction is emitted from the optical device.
In this optical device, light (mixed wave of P-wave and S-wave) from the outside of the reflection surface portion is incident on the shielding plate disposed on the light incident side of the reflection surface portion, and is separated from each other by the polarization separation surface. It is provided so as not to be mixed with one polarized light (P wave or S wave) (S wave in FIG. 7) and to lose its single polarized state (S wave in FIG. 7).
[0011]
In the above-described conventional optical devices described in FIGS. 6 and 7 and Patent Documents 5 and 6, the polarization of light incident on the liquid crystal shutter is made single without using a polarizing film in order to use a single polarization. A 波長 wavelength retardation element (１ ／ λ wavelength plate) or a retardation plate is used together with the separation element (PS separation film) or the birefringent crystal. Plate), it is possible to prevent a large decrease in the amount of light as compared with the case where the plate is used.
However, these conventional optical devices both require a half-wavelength phase delay element in order to align two polarized lights separated by a polarization splitting element into one polarized light having the same vibration direction (polarization direction). ing.
Further, the conventional optical devices described in FIG. 6, Patent Document 5, Patent Document 6 (particularly claims), etc. require expensive lens arrays (fly-eye lenses) upstream or downstream of the polarization separation element. , An expensive diffraction grating, a birefringent crystal, or the like must be used.
Therefore, these conventional optical devices are complicated in structure, expensive, and require labor and time for design and development. In addition, since birefringent crystals such as calcite used in the optical device of Patent Document 6 are difficult to obtain in large size, polarized light supplied to the liquid crystal shutter (polarized light whose polarization direction is aligned in one direction). ) Cannot be made large, so that a large-area mask image cannot be projected on a molding surface made of a photocurable resin, and it is difficult to manufacture a large-sized molded object.
[0012]
Moreover, in these conventional optical devices described in FIGS. 6 and 7 and Patent Documents 5 and 6, etc., when a P-wave and an S-wave are separated by a polarization separation element, or when the P-wave separated by a polarization separation element is used. When the oscillation direction of either one of the wave and the S wave is made to be the same as the oscillation direction of the other polarized light by using a half-wavelength phase delay element, the light intensity becomes nonuniform due to light energy loss and the like. Easy to occur. Therefore, although the light emitted after passing through the half-wavelength phase delay element has its polarization direction (light vibration direction) uniformly aligned in either the P direction or the S direction, the light intensity There is unevenness. For example, in the optical device of FIG. 6, the vibration direction of the P wave directly passing through the PS separation film (polarization separation film) and the S wave reflected by the PS separation film are changed to the P direction through a 1 / 2λ wavelength plate. There is a difference in light intensity between the P wave and the same P wave.
Therefore, when these conventional optical devices are used for optical three-dimensional modeling, the intensity of light applied to a modeling surface through a drawing mask formed of a liquid crystal shutter becomes non-uniform. Unevenness of the three-dimensional object, poor appearance, and the like are likely to occur. In these conventional optical devices, in order to prevent such light intensity unevenness with a single polarized light emitted through a polarization splitting element and a half-wavelength phase delay element, an illuminance uniforming means is provided in the optical path. , Making the optical device more complex and expensive.
[0013]
[Patent Document 1]
JP-A-62-288844
[Patent Document 2]
JP-A-3-227222
[Patent Document 3]
JP-A-7-2905789
[Patent Document 4]
JP-A-8-112866
[Patent Document 5]
JP-A-10-197827
[Patent Document 6]
JP 2000-180262 A
[0014]
[Problems to be solved by the invention]
An object of the present invention is to produce light with a small amount of light emitted from a light source or the like, with high light energy efficiency, from small three-dimensional objects to large three-dimensional objects, with high modeling accuracy, and at a high modeling speed. An object of the present invention is to provide an optical three-dimensional modeling method and an optical three-dimensional modeling device that can be manufactured with good efficiency.
Furthermore, an object of the present invention is to provide a half-wave phase delay element without using expensive devices and means such as an ultraviolet laser, a lens array, a birefringent crystal, and a polarization separation element formed of a crystal lattice. It is a simple and inexpensive device that does not need to be used, and uses an inexpensive light source such as an ordinary ultraviolet lamp to produce three-dimensional objects with high light energy efficiency, high modeling accuracy, high speed, and high productivity. It is an object of the present invention to provide an optical three-dimensional modeling method and an optical three-dimensional modeling device that can be performed.
Then, an object of the present invention is to irradiate a light of uniform light intensity (illuminance) to a modeling surface made of a photocurable resin composition through a drawing mask made of a liquid crystal shutter with a simple and inexpensive device. It is an object of the present invention to provide an optical three-dimensional modeling method and an optical three-dimensional modeling apparatus that can produce a high-quality three-dimensional molded article having higher molding accuracy and mechanical characteristics.
[0015]
[Means for Solving the Problems]
The present inventor has made intensive studies to achieve the above object. As a result, the surface of the photocurable resin composition is irradiated with light through a drawing mask formed of a liquid crystal shutter, and a photocured resin layer having a predetermined cross-sectional shape pattern is sequentially formed to manufacture a three-dimensional structure. In the optical three-dimensional modeling method and the optical three-dimensional modeling apparatus, light emitted from a light source or a light emitting unit is separated into two polarized lights whose vibration directions are orthogonal to each other on a polarization separating surface of a polarization separating element, and the separated light is separated. Of the two polarized lights, only one of the polarized lights that passed through the polarization splitting surface was directly radiated to the modeling surface as it was through the drawing mask composed of the liquid crystal shutter, and the other polarized light separated (reflected) by the polarization splitting surface was Re-reflecting, scattering and / or absorbing away from the drawing mask can result in expensive UV lasers, fly-eye lenses (lens arrays), expensive polarization An extremely simple device without using a separating element, a birefringent crystal, or the like, and without using a half-wavelength phase delay element which is indispensable in the above-described conventional optical device. While maintaining a high light intensity (light energy intensity) of 45% or more, in a single polarization form having a single vibration direction to a drawing mask equipped with a liquid crystal shutter, whereby a small From three-dimensional objects to large three-dimensional objects, it has been found that it can be manufactured with extremely good light energy efficiency, high modeling accuracy, high modeling speed, and high productivity.
In addition, according to this method, since the light intensity (irradiation intensity) of the single polarized light supplied to the drawing mask via the polarization separation element is uniform and the whole is uniform, the objective three-dimensional structure can be made high. It has been found that the three-dimensional molded article that can be manufactured with molding accuracy and that is extremely excellent in mechanical properties, appearance, and the like.
[0016]
Further, the present inventor, when producing a three-dimensional structure by such a method, as a polarization separation element,
.Two polarization separation planes A ₁ And A ₂ A polarization splitting element having at least one pair of structural parts which are arranged to face each other in a V-shaped plane symmetric state;
.Two polarization separation planes A ₁ And A ₂ Are arranged facing each other in a V-shaped plane symmetry state, and the polarization separation surface A ₁ And A ₂ A polarization splitting element having at least one set of structural parts in which a light-shielding surface is arranged at a symmetric plane position; or
・ Polarization separation surface A ₃ Are disposed obliquely to the traveling direction of the light emitted from the light source or the light emitting means, and the polarization separation surface A ₃ A polarization splitting element having at least one set of structural parts having a light shielding surface disposed at a predetermined angle with respect to
Have been found to be preferably used, and the present invention has been completed based on those findings.
[0017]
That is, the present invention
(1) A photocurable resin layer having a predetermined cross-sectional shape pattern is formed by irradiating light to a molding surface made of a photocurable resin composition through a drawing mask having a liquid crystal shutter under control, and then forming the light. A modeling surface is formed by applying one layer of the photocurable resin composition on the cured resin layer, and light is controlled and irradiated to the modeling surface made of the photocurable resin composition via a drawing mask. A method of manufacturing a three-dimensional structure by sequentially repeating the operation of further forming a photocured resin layer having a predetermined cross-sectional shape pattern until a predetermined three-dimensional structure is formed,
Using a polarization separation element having a polarization separation surface to separate light emitted from the light source or the light emitting unit into two polarized lights whose vibration directions are orthogonal to each other on the polarization separation surface of the polarization separation element;
One of the polarized lights separated by the polarized light separating surface passes through the polarized light separating element and is directed to the drawing mask;
The other polarized light separated by the polarized light separating surface is reflected by the polarized light separating surface and then re-reflected, scattered and / or absorbed so as not to pass through the polarized light separating element;
Irradiating the one polarized light that has passed through the polarization separation element onto a modeling surface made of a photocurable resin composition through a drawing mask having a liquid crystal shutter capable of blocking and transmitting light in a small area, Forming a photocured resin layer having a predetermined cross-sectional pattern corresponding to the mask image of
An optical three-dimensional modeling method characterized by the following.
[0018]
And the present invention
(2) Two polarization separation planes A as polarization separation elements ₁ And A ₂ Using a polarization splitting element having at least one set of structural parts arranged to face each other in a V-shaped plane symmetric state;
The light emitted from the light source or the light emitting means is converted to the polarization separation surface A of the polarization separation element. ₁ And A ₂ Respectively, separates into two polarized lights whose vibration directions are orthogonal to each other, one of the separated polarized lights is passed through a polarization separating element and directed toward a drawing mask, and the other polarized light is polarized light separation plane A. ₁ And A ₂ Reflected by each of the;
Polarization separation surface A ₁ The other polarized light reflected by the ₂ Polarized light separating surface A ₂ And the polarization separation surface A ₂ The other polarized light reflected by the ₁ Polarized light separating surface A ₁ To prevent the other polarized light from passing through the polarization splitting element;
(3) An optical three-dimensional modeling method according to the above (1).
[0019]
Further, the present invention provides
(3) Two polarization separation planes A as polarization separation elements ₁ And A ₂ Are arranged facing each other in a V-shaped plane symmetry state, and the polarization separation surface A ₁ And A ₂ Using a polarization splitting element having at least one set of structural parts in which the light-shielding surface B is disposed at the position of the symmetry plane;
The light emitted from the light source or the light emitting means is converted into two polarized light separating surfaces A of the polarized light separating element. ₁ And A ₂ Respectively, separates into two polarized lights whose vibration directions are orthogonal to each other, one of the separated polarized lights is passed through a polarization separating element and directed toward a drawing mask, and the other polarized light is polarized light separation plane A. ₁ And A ₂ To reflect;
Polarization separation surface A ₁ And A ₂ Directing the other polarized light reflected by the light source toward the light-shielding surface B and re-reflecting, scattering and / or absorbing the other polarized light so that the other polarized light does not pass through the polarization separation element;
(3) An optical three-dimensional modeling method according to the above (1).
[0020]
Also, the present invention
(4) As a polarization separation element, a polarization separation surface A ₃ Are arranged obliquely to the traveling direction of the light emitted from the light source or the light emitting means, and the light-shielding surface B is provided as the polarization separating surface A. ₃ Using a polarization splitting element having at least one set of structural parts opposed to each other at a predetermined angle;
The light emitted from the light source or the light emitting means is converted into a polarized light separating surface A. ₃ , The light is separated into two polarized lights whose vibration directions are orthogonal to each other. ₃ To the drawing mask, and the other polarized light is polarized light separation plane A. ₃ To reflect;
Polarization separation surface A ₃ Directing the other polarized light reflected by the light source toward the light-shielding surface B and re-reflecting, scattering and / or absorbing the other polarized light so that the other polarized light does not pass through the polarization separation element;
(3) An optical three-dimensional modeling method according to the above (1).
[0021]
Also, the present invention
(5) The one of the above-mentioned (1) to (1) to which the one polarized light which has passed through the polarization separation element is supplied to a drawing mask through a condenser lens, and light of a predetermined mask image passing through the drawing mask is irradiated to a modeling surface through a projection lens. The optical three-dimensional modeling method according to any one of (4).
[0022]
And the present invention
(6) a light source or light emitting means;
.Having a polarization separation surface for separating the light emitted from the light source or the light emission means into two polarization lights whose vibration directions are orthogonal to each other, and one of the two polarization lights separated by the polarization separation plane is polarization separation light A polarization splitting element that passes through the element and reflects the other polarized light on the polarization splitting surface and then re-reflects, scatters, and / or absorbs the light so as not to pass through the polarization splitting element;
A drawing mask arranged on the downstream side of the polarization splitting element, the drawing mask including a plurality of minute liquid crystal shutters capable of blocking and transmitting light in a minute area; and
Means for forming a shaped surface made of the photocurable resin composition;
It is an optical three-dimensional printing apparatus characterized by having.
[0023]
Further, the present invention provides
(7) The polarization separation element
-Two polarization separations that separate the light emitted from the light source or the light emitting means into two polarized lights whose vibration directions are orthogonal to each other, allow one of the two polarized lights to pass, and reflect the other polarized light. Surface A ₁ And A ₂ , A polarizing beam splitter having one or more sets of structural parts arranged opposite to each other in a V-shaped plane symmetric state [hereinafter, this may be referred to as a “polarized light separating element (2a)”];
-Two polarization separations that separate the light emitted from the light source or the light emitting means into two polarized lights whose vibration directions are orthogonal to each other, allow one of the two polarized lights to pass, and reflect the other polarized light. Surface A ₁ And A ₂ Are arranged facing each other in a V-shaped plane symmetry state, and the polarization separation surface A ₁ And polarization separation surface A ₂ A polarizing beam splitter having one or more sets of structural portions in which a light-shielding surface B is arranged at a symmetric plane position [hereinafter, this may be referred to as a “polarized beam splitting element (2b)”]; or
A polarization separation surface A that separates the light emitted from the light source or the light emitting means into two polarized lights whose vibration directions are orthogonal to each other, passes one of the two polarized lights, and reflects the other polarized light. ₃ Are arranged obliquely to the traveling direction of the light emitted from the light source or the light emitting means, and the light-shielding surface B is provided as the polarization separating surface A. ₃ A polarizing beam splitter having one or more sets of structural parts opposed to each other at a predetermined angle [hereinafter, this may be referred to as “polarizing beam splitting element (2c)”];
The optical three-dimensional modeling apparatus according to (6) above.
[0024]
Also, the present invention
(8) The optics of (6) or (7), wherein the polarization splitting surface of the polarization splitting element is arranged at an angle of 40 ° to 50 ° with respect to the traveling direction of the light emitted from the light source or the light emitting means. It is a three-dimensional modeling device.
[0025]
And the present invention
(9) It has a polarization separation surface that separates the light emitted from the light source or the light emission unit into two polarization lights whose vibration directions are orthogonal to each other, and one of the two polarization lights separated by the polarization separation surface is A polarization splitting element configured to pass through the polarization splitting element and reflect the other polarized light on the polarization splitting surface, and then re-reflect, scatter and / or absorb the light so as not to pass through the polarization splitting element;
A drawing mask comprising a plurality of minute liquid crystal shutters disposed downstream of the polarization separation element and capable of blocking and transmitting light in a minute area;
An optical device having:
-Two polarization separations that separate the light emitted from the light source or the light emitting means into two polarized lights whose vibration directions are orthogonal to each other, allow one of the two polarized lights to pass, and reflect the other polarized light. Surface A ₁ And A ₂ (2a) having at least one pair of structural parts which face each other in a V-shaped plane symmetric state;
-Two polarization separations that separate the light emitted from the light source or the light emitting means into two polarized lights whose vibration directions are orthogonal to each other, allow one of the two polarized lights to pass, and reflect the other polarized light. Surface A ₁ And A ₂ Are arranged facing each other in a V-shaped plane symmetry state, and the polarization separation surface A ₁ And polarization separation surface A ₂ A polarization splitting element (2b) having at least one set of structural parts in which a light-shielding surface B is arranged at a symmetric plane position;
A polarization separation surface A that separates the light emitted from the light source or the light emitting means into two polarized lights whose vibration directions are orthogonal to each other, passes one of the two polarized lights, and reflects the other polarized light. ₃ Are arranged obliquely to the traveling direction of the light emitted from the light source or the light emitting means, and the light-shielding surface B is provided as the polarization separating surface A. ₃ A polarization splitting element (2c) having at least one set of structural parts opposed to each other at a predetermined angle;
An optical device, characterized by:
(10) The optical device according to (9), wherein the polarization splitting surface of the polarization splitting element is arranged at an angle of 40 ° to 50 ° with respect to the traveling direction of the light emitted from the light source or the light emitting means;
It is.
[0026]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described in detail.
The optical three-dimensional modeling method of the present invention is to form a photocured resin layer having a predetermined cross-sectional shape pattern by irradiating light on the surface of the photocurable resin composition under control via a drawing mask, One layer of the photo-curable resin composition is applied on the photo-cured resin layer, and the surface (modeling surface) of the photo-curable resin composition is irradiated with light under control via a drawing mask to a predetermined level. The optical molding of the present invention is performed by adopting a molding operation for manufacturing a three-dimensional molded object by sequentially repeating an operation of further forming a photocured resin layer having a cross-sectional shape pattern until a predetermined three-dimensional molded object is formed. The three-dimensional printing apparatus is used in such an optical three-dimensional printing technique.
[0027]
In general, the molding operation of the present invention is performed by disposing a molding table in a molding bath filled with a liquid photocurable resin composition, and lowering the molding table to form one layer of liquid photocurable on the molding table surface. A resin composition layer (modeling surface) is formed, and a light-cured resin layer having a predetermined pattern and thickness by irradiating light thereto through a drawing mask under control (hereinafter sometimes referred to as a “photo-cured layer”) Is formed, the molding table is further lowered to form a liquid photocurable resin composition layer for one layer on the photocurable layer surface, and the light is radiated under control through a drawing mask under a predetermined pattern. And a molding bath method in which a step of integrally forming a photocurable layer having a thickness and a thickness is repeatedly performed.
[0028]
In the above-described molding operation of the present invention, for example, a molding table is placed in a gas atmosphere, and a layer of a liquid, paste, powder, or thin-film photocurable resin composition is placed on the molding table surface. After applying light under control through a drawing mask to form a photocured layer having a predetermined pattern and thickness, a liquid, paste, powder or thin film of one layer is formed on the photocured layer surface. A method of repeatedly applying a photocurable resin composition and irradiating light under control via the drawing mask to integrally form a photocurable layer having a predetermined pattern and thickness is performed. You can also. In the case of this method, a method in which a molding table or a photocurable layer is turned upward, a photocurable resin composition is applied to the upper surface, and light is irradiated through a drawing mask to sequentially form a photocurable layer is formed. The molding table or light-curing layer may be arranged vertically or obliquely, the photo-curing resin layer may be applied on the surface of the molding table or the light-curing layer, and light curing may be performed by irradiating light through a drawing mask. A method of sequentially forming layers may be adopted, or a photo-setting resin layer composition may be applied to the modeling table surface or the photo-curing layer surface by placing the modeling table or the photo-curing layer downward and drawing. A method of irradiating light through a mask and sequentially forming a photo-cured layer on the lower side may be adopted. In applying the photocurable resin composition to the modeling table surface or the photocurable layer surface, for example, it is possible to employ an appropriate method such as blade coating, casting coating, roller coating, transfer coating, brush coating, spray coating, and the like. it can.
[0029]
In the present invention, in performing the above-described stereolithography operation, a drawing mask including a plurality of minute liquid crystal shutters capable of blocking and transmitting light in a minute area (hereinafter, referred to as a “liquid crystal drawing mask”) Is used). Then, from the upstream to the downstream, a light source or a light emitting unit, a polarization separation element, and a liquid crystal drawing mask are arranged in this order. Through a predetermined mask image formed by the liquid crystal drawing mask, light of a predetermined pattern shape is applied to a modeling surface formed of a photocurable resin composition formed by a modeling surface forming apparatus, and a predetermined cross-sectional shape is formed on the modeling surface. A photocured resin layer having a pattern is formed.
[0030]
The polarized light separating element has a polarized light separating surface, and the light emitted from the light source or the light emitting means is separated into two polarized lights (P wave and S wave) whose vibration directions are orthogonal to each other at the polarized light separating surface and separated from each other. Only one of the P wave and the S wave passes through the polarization splitting surface (polarization splitting element) and proceeds toward the liquid crystal drawing mask. The other polarized light (the S wave when the P wave passes through the polarization separation surface, and the P wave when the S wave passes through the polarization separation surface) is reflected by the polarization separation surface, and then reflected by the polarization separation surface (the polarization separation surface). ) So that they do not pass through the element).
[0031]
The polarization separation element used in the optical three-dimensional modeling technology of the present invention has a polarization separation surface that separates light incident on the polarization separation element into two polarized lights (P wave and S wave) whose vibration directions are orthogonal to each other, In addition, any polarized light separating element having a structure in which only one polarized light of the two separated polarized light passes through the polarized light separating element and the other polarized light does not pass through the polarized light separating surface (polarized light separating element). Can also be used.
Among them, in the present invention, the following polarized light separating elements (2a) to (2c) are preferably used as polarized light separating elements.
[0032]
・ Polarization separation element (2a) :
Two polarized light separating surfaces that separate light emitted from a light source or a light emitting unit into two polarized lights whose vibration directions are orthogonal to each other, allow one of the two polarized lights to pass, and reflect the other polarized light. A ₁ And A ₂ Is a polarization splitting element having at least one set of structural parts which face each other in a V-shaped plane symmetry state.
・ Polarization separation element (2b) :
Two polarized light separating surfaces that separate light emitted from a light source or a light emitting unit into two polarized lights whose vibration directions are orthogonal to each other, allow one of the two polarized lights to pass, and reflect the other polarized light. A ₁ And A ₂ Are arranged facing each other in a V-shaped plane symmetry state, and the polarization separation surface A ₁ And polarization separation surface A ₂ A polarization splitting element having at least one set of structural parts in which a light-shielding surface B is arranged at a symmetric plane position.
・ Polarization separation element (2c) :
A polarization separation surface A that separates light emitted from a light source or a light emitting unit into two polarized lights whose vibration directions are orthogonal to each other, passes one of the two polarized lights, and reflects the other polarized light. ₃ Are arranged obliquely to the traveling direction of the light emitted from the light source or the light emitting means, and the light-shielding surface B is provided as the polarization separating surface A. ₃ A polarization splitting element having at least one set of structural parts opposed to each other at a predetermined angle.
[0033]
Although not limited, the polarization splitting elements (2a) to (2c) preferably used in the present invention will be described below with reference to the drawings. FIG. 1 shows a typical example of the polarization beam splitter (2a), FIG. 2 shows a typical example of the polarization beam splitter (2b), and FIG. 3 shows a typical example of the polarization beam splitter (2c).
First, the polarization separation element (2a) will be described with reference to FIG.
The polarization separation element (2a) has a polarization separation surface A ₁ And A ₂ Has one or two or more sets of structural parts facing each other in a V-shaped plane symmetric state (FIG. 1 shows a state in which two sets of the structural parts are arranged). Light emitted from a light source or light emitting means (not shown) including two polarized lights (P wave and S wave) whose vibration directions are orthogonal to each other (P wave is shown by a solid line and S wave is shown by a dotted line) is polarized light separation. Surface A ₁ And A ₂ And one of the two polarized lights (illustrated by a P wave in FIG. 1) is a polarized light separating plane A. ₁ And A ₂ Pass through. The other polarized light (illustrated by S wave in FIG. 1) is polarized light separating surface A ₁ And A ₂ Is reflected by Polarization separation surface A ₁ (S wave) reflected by the ₁ Separation plane A opposite to ₂ In the direction of ₂ And is returned to the incident direction (light source or light emitting means). Also, the polarization separation surface A ₂ (S wave) reflected by the ₂ Separation plane A opposite to ₁ In the direction of ₁ And is returned to the incident direction (light source or light emitting means).
In the polarization separation element (2a), the polarization separation plane A with respect to the traveling direction of light from the light source or the light emitting means. ₁ And A ₂ Of the arrangement angle α ₁ And α ₂ Allows only one polarization (eg, P-wave) to pass through the polarization separation element (2a) at a higher rate and the other polarization (eg, S-wave) not to completely pass through the polarization separation element (2a). From the viewpoint, it is preferably 40 ° to 50 °, more preferably 42 ° to 48 °, and further preferably 45 °.
[0034]
As shown in FIG. 1, the polarization beam splitting element (2a) does not use any optical member such as an expensive lens array (flyal lens), birefringent crystal, crystal lattice, etc. Two polarization separation planes A without using any wavelength phase delay element ₁ And A ₂ Is simply arranged opposite to the V-shape in plane symmetry, and only one polarization (P-wave in FIG. 1) of two polarizations (P-wave and S-wave) emitted from the light source or the light-emitting means is polarization-separated. After passing through the element (2a) and reflecting the other polarized light (S-wave in FIG. 1), the liquid crystal drawing mask (not shown) arranged downstream of the polarized light separating element (2a) has an oscillation direction of 1 Only a single polarized light (P wave in FIG. 1) aligned in one direction can be extremely efficiently incident. In the polarization separation element (2a), only one polarization (for example, P-wave) of two polarizations (P-wave and S-wave) emitted from the light source or the light emission unit is the polarization separation plane A. ₁ And A ₂ The polarization direction (vibration direction) of the other polarized light (for example, S wave) is emitted from the polarization separation element (2a) through the half-wavelength phase delay element, and the polarization direction of one polarized light (P wave) is used. (Vibration direction), and since the operation of supplying the polarized light to the liquid crystal drawing mask together with the polarized light having passed through the polarization separating surface is not performed, one polarized light (for example, P The wave is uniform throughout and has no unevenness in light intensity (illuminance). Therefore, it is possible to irradiate the single-polarized light having passed through the polarization separation element (2a) to the modeling surface made of the photo-curable resin composition through the liquid crystal drawing mask with uniform light (light intensity). This makes it possible to obtain a three-dimensional molded article having extremely excellent molding accuracy, mechanical properties, appearance, and the like.
[0035]
Next, the polarization separation element (2b) will be described with reference to FIG.
The polarization separation element (2b) has a polarization separation surface A ₁ And A ₂ Are arranged facing each other in a V-shaped plane symmetry state, and the polarization separation surface A ₁ And polarization separation surface A ₂ Has one or two or more sets of structural parts in which the light-shielding surface B is arranged at the symmetry plane position (center position) (FIG. 2 shows a state in which two sets of the structural parts are arranged). Light emitted from a light source or light emitting means (not shown) including two polarized lights (P wave and S wave) whose vibration directions are orthogonal to each other (P wave is shown by a solid line and S wave is shown by a dotted line) is polarized light separation. Surface A ₁ And A ₂ And one of the two polarized lights (illustrated by a P wave in FIG. 2) is a polarization separation plane A. ₁ And A ₂ Pass through. The other polarized light (illustrated as an S wave in FIG. 2) is polarized light separating surface A. ₁ And A ₂ Is reflected by Polarization separation surface A ₁ And A ₂ The other polarized light (S wave) reflected by the ₁ And polarization separation surface A ₂ Collide with the light-shielding surface B disposed between ₁ And A ₂ Is re-reflected, scattered and / or absorbed by the light shielding surface B so as not to pass through.
As the light-shielding surface B, a light absorber (for example, a light absorber formed using a black pigment such as carbon black) or a reflector is preferably used. When the light-shielding surface B is made of a light absorber, the polarization separation surface A ₁ And A ₂ The other polarized light (S-wave) reflected by is absorbed by the light-shielding surface B (light absorber), so that the other polarized light (S-wave) is prevented from passing through the polarization separation element (2b). be able to. When the light shielding surface B is made of a reflector, the polarization separation surface A ₁ And A ₂ The polarized light (S wave) reflected by the light is re-reflected by the light-shielding surface B (reflector) to form a polarized light separating surface A. ₁ And A ₂ Back to the direction of ₁ And A ₂ And is returned again in the incident direction (light source or light emitting means).
[0036]
In the polarization separation element (2b), the polarization separation plane A with respect to the traveling direction of light from the light source or the light emitting means. ₁ And A ₂ Of the arrangement angle α ₁ And α ₂ Is preferably 40 ° to 50 °, more preferably 42 ° to 48 °, and even more preferably 45 °. Also, the polarization separation surface A ₁ And A ₂ Angle β between the light-shielding surface B and ₁ And β ₂ Is preferably 40 ° to 50 °, more preferably 42 ° to 48 °, and even more preferably 45 °. The angle α ₁ , Α ₂ , Β ₁ And β ₂ Is set to the above angle, so that only one polarized light (for example, P wave) passes through the polarization separation element (2a) at a higher rate and the other polarization (for example, S wave) completely passes through the polarization separation element (2a). Can be prevented from passing through.
[0037]
Like the polarization splitting element (2a), the polarization splitting element (2b) does not use any optical member such as an expensive lens array (flyal lens), a birefringent crystal, a crystal lattice, or the like. Two polarization separation planes A without using any half-wave phase delay element ₁ And A ₂ Are arranged opposite to each other in a V-shape in plane symmetry, and both polarization separation surfaces A ₁ And A ₂ By simply arranging the light-shielding surface B at the plane symmetrical position (central portion), only one polarized light (for example, P-wave) of two polarized lights (P-wave and S-wave) emitted from the light source or the light emitting means is emitted. A liquid crystal drawing mask disposed on the downstream side of the polarization separation element (2b) by passing through the polarization separation element (2b) and re-reflecting, scattering and / or absorbing the other polarized light (for example, S wave) on the light shielding surface B. (Not shown), only a single polarized light (for example, P-wave) whose vibration direction is aligned in one direction can be extremely efficiently incident.
In the polarization separation element (2b), only one polarization (for example, P-wave) of the two polarizations (P-wave and S-wave) emitted from the light source or the light emission unit is the polarization separation plane A. ₁ And A ₂ The polarization direction (vibration direction) of the other polarized light (for example, S wave) is emitted from the polarization splitting element (2b) through the half-wavelength phase delay element. Since the operation of supplying the liquid crystal drawing mask together with the one polarized light in the same polarization direction (vibration direction) is not performed, one polarized light (for example, P wave) emitted from the polarization separation element (2b) is There is no unevenness in light intensity (illuminance) and the like as a whole. Therefore, it is possible to irradiate the single-polarized light that has passed through the polarization separation element (2b) to the modeling surface made of the photocurable resin composition with uniform illuminance (intensity) through the liquid crystal drawing mask, thereby. It is possible to obtain a three-dimensional molded article having extremely excellent molding accuracy, mechanical properties, appearance, and the like.
[0038]
The polarization beam splitting element (2c) will be described with reference to FIG.
The polarization separation element (2c) is a polarization separation surface A ₃ Are arranged obliquely to the traveling direction of the light emitted from the light source or the light emitting means, and the light-shielding surface B is provided as the polarization separating surface A. ₃ Given angle β ₃ Has one or two or more sets of structural parts opposed to each other (FIG. 3 shows a state in which four sets of the structural parts are arranged). Light emitted from a light source or light emitting means (not shown) including two polarized lights (P wave and S wave) whose vibration directions are orthogonal to each other (P wave is shown by a solid line and S wave is shown by a dotted line) is polarized light separation. Surface A ₃ And one of the two polarized lights (illustrated by a P wave in FIG. 3) is ₃ Pass through. The other polarized light (illustrated as an S wave in FIG. 3) is polarized light separating surface A. ₃ Is reflected by Polarization separation surface A ₃ The other polarized light (S wave) reflected by the ₃ Given angle β ₃ Collides with the light-shielding surface B disposed opposite to the ₃ Is re-reflected, scattered and / or absorbed by the light shielding surface B so as not to pass through.
As the light shielding surface B, a light absorber or a reflector is preferably used as in the case of the polarization separation element (2b). When the light-shielding surface B is made of a light absorber, the polarization separation surface A ₃ Is reflected by the light-shielding surface B (light absorber), so that the other polarized light (eg, S-wave) passes through the polarization separation element (2c). Can be blocked. When the light shielding surface B is made of a reflector, the polarization separation surface A ₃ Is reflected by the light-shielding surface B (reflector) and is reflected again by the polarization splitting surface A. ₃ Back to the direction of ₃ And is returned again in the incident direction (light source or light emitting means).
[0039]
In the polarization separation element (2c), the polarization separation plane A with respect to the traveling direction of light from the light source or the light emitting means. ₃ Of the arrangement angle α ₃ Is preferably 40 ° to 50 °, more preferably 42 ° to 48 °, and even more preferably 45 °. Also, the polarization separation surface A ₃ Angle β between the light-shielding surface B and ₃ Is preferably 40 ° to 50 °, more preferably 42 ° to 48 °, and even more preferably 45 °. Angle α ₃ And β ₃ Is set to the above angle, so that only one polarized light (for example, P wave) passes through the polarization separation element (2c) at a higher rate and the other polarization (for example, S wave) completely passes through the polarization separation element (2a). Can be prevented from passing through.
[0040]
The polarization separation element (2c) does not use any optical member such as an expensive lens array (flyal lens), birefringent crystal, crystal lattice, etc., like the polarization separation elements (2a) and (2b). And without using any half-wavelength phase delay element, ₃ Are arranged obliquely to the traveling direction of light, and the light-shielding surface B is ₃ , Only one polarization (for example, P-wave) of the two polarizations (P-wave and S-wave) emitted from the light source or the light-emitting means is disposed at a predetermined angle with respect to the polarization separation element (2c). And the other polarized light (for example, S-wave) is re-reflected, scattered and / or absorbed by the light-shielding surface B, and applied to a liquid crystal drawing mask (not shown) arranged downstream of the polarization separation element (2c). In addition, only a single polarized light (for example, P wave) whose vibration direction is aligned in one direction can be extremely efficiently incident. Then, in the polarization separation element (2c), only one polarization (for example, P-wave) of the two polarizations (P-wave and S-wave) emitted from the light source or the light emission unit is the polarization separation plane A. ₃ The polarization direction (oscillation direction) of the other polarized light (for example, S wave) is output from the polarization splitting element (2c) through the half-wavelength phase delay element. Since the operation of aligning with the polarization direction (vibration direction) and supplying the polarized light to the liquid crystal drawing mask together with the one polarized light is not performed, one polarized light (for example, P wave) emitted from the polarization separation element (2c) is entirely And there is no unevenness in light intensity (illuminance). Therefore, it is possible to irradiate the single polarized light that has passed through the polarization separation element (2c) to the modeling surface made of the photocurable resin composition with a uniform light intensity (illuminance) through the liquid crystal drawing mask, thereby forming It is possible to obtain a three-dimensional structure having extremely excellent accuracy, mechanical properties, appearance, and the like.
[0041]
The polarization separation elements (2a) to (2c) use a transparent glass, a transparent plastic or the like as a base material, and a polarization separation surface A in the base material. ₁ , A ₂ , A ₃ In addition, the light-shielding surface B is arranged in the arrangement state illustrated in, for example, FIGS. 1 to 3 and the like, and the entirety of the polarization separation elements (2a) to (2c) is formed to be substantially plate-shaped. Can be. At this time, parts having one polarization splitting surface are manufactured on a transparent base material, and the polarization splitting elements (2a) to (2c) are manufactured by assembling a plurality of parts into the structure shown in FIGS. You can also. The method for forming the polarization separation surface on the substrate is not particularly limited, and any method conventionally used in the production of this type of optical product may be employed.
[0042]
Polarization separation plane A in polarization separation element (2a) ₁ -Polarization separation surface A ₂ The number of sets of structural parts consisting of the polarization separation plane A in the polarization separation element (2b) ₁ -Shielding surface B-Polarization separating surface A ₂ The number of sets of structural parts made up of the polarization splitting surface A in the polarization splitting element (2c) ₃ -The number of sets of the structural part composed of the light-shielding surface B depends on the size of the three-dimensional object to be manufactured, the type and size of the light source, the polarization separation surface A ₁ , A ₂ , A ₃ And the size of the liquid crystal drawing mask can be determined as appropriate. In the case of arranging a plurality of the structural parts, it is preferable to arrange the adjacent structural parts so as to be close to each other as shown in FIGS. 1 to 3, whereby the light is emitted from the polarization splitting elements (2a) to (2c). The light density of the single polarized light to be obtained can be made uniform.
[0043]
In practicing the present invention, for example, as illustrated in FIG. 4, a light source or a light emitting unit (1), a polarization separation element (2) [preferably any of the polarization separation elements (2a) to (2c); 1 uses a polarization separation element (2a)] and a liquid crystal drawing mask (3) in this order, and if necessary, a condenser lens between the polarization separation element (2) and the liquid crystal drawing mask (3). In (4), a projection lens (6) is arranged between the liquid crystal drawing mask (3) and the modeling surface (5) to perform optical three-dimensional modeling.
[0044]
The type of light source used in the optical three-dimensional modeling of the present invention is not particularly limited, and may be any light source that can be used in the optical three-dimensional modeling. For example, a xenon lamp, a metal halide lamp, a mercury lamp, a fluorescent lamp, and a halogen lamp , Incandescent lamps, Ar lasers, He-Cd lasers, LD lasers (semiconductor-excited solid-state lasers), and the like. In particular, in the case of the present invention, without using an expensive light source such as a laser light device conventionally used in an optical three-dimensional molding method of irradiating a molding surface with spot-shaped light, a xenon lamp, a metal halide lamp, An inexpensive general-purpose light source such as a mercury lamp, a fluorescent lamp, a halogen lamp, and an incandescent lamp can be used, and therefore, the optical three-dimensional printing apparatus can be made inexpensive and easy to use.
The shape, size, and number of light sources are not particularly limited, and can be appropriately selected depending on the shape and size of the drawing mask, the shape and size of the light-cured cross-sectional shape pattern to be formed, and the light source is, for example, The light source may be point-like, spherical, rod-like, or sheet-like, or point-like or spherical light sources may be directly arranged in one or more rows on the back side of the drawing mask.
Furthermore, instead of directly supplying the light from the light source to the polarization separation element, the light from the light source is guided to a light emission means such as a lot lens through an optical fiber, a light guide or other light transmission means, and the light is transmitted to the polarization separation element. You may supply (lead). In order to improve the molding speed, a method of condensing light using a plurality of light sources and increasing light energy may be adopted. In particular, when an optical fiber or a light guide is used, there is an advantage that a plurality of light sources can be easily collected.
[0045]
In the above, a single polarized light (either a P-wave or an S-wave) having the same vibration direction passing through the polarization separation element (2) is directly guided to the liquid crystal drawing mask (2), or FIG. In some cases, the light is condensed by a condensing lens (4) or the like and then guided to a liquid crystal drawing mask (3). The liquid crystal drawing mask (3) used in the optical three-dimensional modeling apparatus of the present invention does not have a conventional general-purpose polarizing film that causes a large decrease in the amount of light at the entrance side, and the above-described polarization separation element (2) [ Preferably, any one of the polarization separation elements (2a) to (2c)] is efficiently guided to the liquid crystal drawing mask (3) as polarized light having a single vibration direction while maintaining a high light amount of 45% or more of the initial state. I will
The polarized light having a single oscillation direction guided into the liquid crystal is disposed on the liquid crystal drawing mask (3) on the exit side of the liquid crystal drawing mask (3) due to the arrangement state of the liquid crystal caused by the presence / absence and strength of the voltage load. A predetermined planar mask image formed by a microswitching action (on / off action) by the cooperation of polarization directions of a polarizing film (in FIG. 4, the polarizing film disposed on the exit side of the liquid crystal drawing mask (3) is not shown). Through the process, light having a predetermined shape pattern is irradiated on a molding surface (5) made of a photocurable resin, and the resin at the light-irradiated portion is cured to form a cured layer having a predetermined photocured cross-sectional shape pattern. Formed on the surface.
[0046]
In the above description, as illustrated in FIG. 4, a projection lens (6) and the like are arranged between a liquid crystal drawing mask (3) and a modeling surface (5) made of a photo-curable resin composition to form a liquid crystal drawing mask. When the predetermined mask image light emitted through (3) is formed into an image by the projection lens (6) and then irradiated onto the modeling surface (5), a clearer photocurable layer can be formed, and The molding accuracy of the molded object is further improved.
[0047]
The shape, structure, size, number of pixels, type, and the like of the liquid crystal drawing mask (3) for forming a predetermined drawing mask image by the microswitch operation (on / off operation) are not particularly limited, and the entrance side (single A liquid crystal drawing mask in which no polarizing film (polarizing plate) is arranged on the polarized light introduction side aligned with the vibration direction and a polarizing film (polarizing plate) is arranged only on the exit side (light exit side). Any liquid crystal drawing mask, such as a liquid crystal drawing mask having a beam splitter disposed on the light output side) and having a minute liquid crystal shutter capable of forming a desired mask image, can be used.
The liquid crystal drawing mask (3) may have, for example, a rectangular shape, a square shape, a rectangular shape elongated in the horizontal direction, or other shapes.
As a method of forming a mask image with the liquid crystal drawing mask (3), for example, information on a mask image to be formed is stored in a computer or the like in advance, and according to the information, liquid crystal drawing is performed for each layer at the time of modeling. A method of changing the mask image by the mask 5 can be adopted.
[0048]
In the present invention, the size and shape of the three-dimensional object to be manufactured are adjusted by adjusting the size (area and the like) of the polarization separation element (2), the installation distance from the light source or the light emitting unit, the optical system for illumination, and the like. Depending on the situation, a mask image from a small area to a wide area can be formed.
Further, in the present invention, it is possible to prevent the occurrence of unevenness in light intensity on the molding surface, which is caused by the conventional optical three-dimensional molding technology as described in Patent Documents 1 to 4 using a liquid crystal drawing mask. From this point, the modeling accuracy can be improved.
[0049]
In performing three-dimensional modeling using the optical three-dimensional modeling apparatus of the present invention, a light source or a light emitting unit (light emitting unit) (1), a polarization separation element (2), a liquid crystal drawing mask (3), etc. In a state where the device is fixed, the light of the pattern corresponding to the mask image formed by the liquid crystal drawing mask (3) for each layer of the photocurable resin composition at the time of stereolithography is applied to the photocurable resin composition. Or a light source or a device for emitting light from a light source (1), a polarization separation element (2), a liquid crystal drawing mask (3), or the like. The shaping surface (5) made of the photocurable resin composition is continuously moved with respect to the shaping surface (5) made of the object, and at this time, the mask image by the liquid crystal drawing mask 5 is dynamically changed in accordance with the movement. ) Is irradiated with light corresponding to the mask image The curable resin may be subjected to shaping while curing.
[0050]
In the case of using the optical three-dimensional modeling apparatus and the optical three-dimensional modeling method of the present invention, the amount of polarized light aligned in a single vibration direction, that is, the amount of polarized light (light) when introduced into the liquid crystal drawing mask (3). Is maintained at 45% or more of the amount of light (light intensity, illuminance, etc.) emitted from the light source or the light emitting means. The high light quantity maintaining ratio of 45% or more is almost the same even if the light emitted from the light source or the light emitting means is short-wavelength ultraviolet light widely used in optical three-dimensional modeling. In this case, a high-energy light having a predetermined pattern corresponding to a mask image formed by the liquid crystal drawing mask (3) can be applied to the molding surface made of the photocurable resin composition, thereby achieving dimensional accuracy. A three-dimensional object excellent in appearance, mechanical properties, and appearance can be manufactured with high productivity at a high molding speed.
[0051]
The type of the photocurable resin composition used in the present invention is not particularly limited, and any liquid, paste, powder, thin film, etc. photocurable resin compositions that can be used for stereolithography can be used.
In the present invention, various oligomers such as urethane acrylate oligomer, epoxy acrylate oligomer, ester acrylate oligomer, and polyfunctional epoxy resin, which are conventionally used in photolithography as a photocurable resin composition; isobornyl acrylate; Isobornyl methacrylate, dicyclopentenyl acrylate, dicyclopentenyl methacrylate, dicyclopentenyloxyethyl acrylate, dicyclopentenyloxyethyl methacrylate, dicyclopetanyl acrylate, dicyclopetanyl methacrylate, bornyl acrylate, bornyl methacrylate , 2-hydroxyethyl acrylate, cyclohexyl acrylate, 2-hydroxypropyl acrylate, phenoxyethyl acrylate, mol Acrylic compounds such as phosphorus acrylamide, morpholine methacrylamide, and acrylamide; and various monofunctional vinyl compounds such as N-vinylpyrrolidone, N-vinylcaprolactam, vinyl acetate, and styrene; trimethylolpropane triacrylate, ethylene oxide-modified trimethylolpropane Triacrylate, ethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol diacrylate, 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, dicyclopentanyl diacrylate, Polyester diacrylate, ethylene oxide-modified bisphenol A diacrylate, pentaerythritol triacrylate Polyfunctional vinyl compounds such as acrylate, pentaerythritol tetraacrylate, propylene oxide-modified trimethylolpropane triacrylate, propylene oxide-modified bisphenol A diacrylate, and tris (acryloxyethyl) isocyanurate; hydrogenated bisphenol A diglycidyl ether; 4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, 2- (3,4-epoxycyclohexyl-5,5-spiro-3,4-epoxy) cyclohexane-meta-dioxane, bis (3,4-epoxy It is possible to use a photocurable resin composition containing one or more kinds of various epoxy compounds such as (cyclohexylmethyl) adipate and a photopolymerization initiator and, if necessary, a sensitizer. it can.
In addition, the photocurable resin composition used in the present invention, in addition to the components described above, if necessary, a leveling agent, a surfactant other than a phosphate ester-based surfactant, an organic polymer modifier, It may contain an organic plasticizer and the like.
[0052]
The photocurable resin composition used in the present invention may contain a filler such as solid fine particles or whiskers, if necessary. Use of a photocurable resin composition containing a filler can improve dimensional accuracy by reducing volume shrinkage during curing, improve mechanical properties and heat resistance, and the like.
Examples of the solid fine particles used as the filler include inorganic fine particles such as carbon black fine particles, polystyrene fine particles, polyethylene fine particles, polypropylene fine particles, acrylic resin fine particles, and organic polymer fine particles such as synthetic rubber fine particles. One or more kinds can be used. The particle size of the solid fine particles is not particularly limited, but generally, those having an average particle size of 200 μm or less, particularly 100 μm or less are preferably used.
[0053]
The whiskers preferably have a diameter of 0.3 to 1 μm, particularly 0.3 to 0.7 μm, a length of 10 to 70 μm, particularly 20 to 50 μm, and an aspect ratio of 10 to 100, particularly 20 to 70 μm. Used. Here, the dimensions and aspect ratio of the whiskers are dimensions and aspect ratios measured using a laser diffraction / scattering particle size distribution analyzer. The type of whisker is not particularly limited, and examples thereof include aluminum borate-based whiskers, aluminum oxide-based whiskers, aluminum nitride-based whisker water, magnesium oxide-based whiskers, and titanium oxide-based whiskers. Species or two or more can be used.
[0054]
When using a photocurable resin composition containing solid fine particles and / or whiskers, the solid fine particles preferably contain 5 to 70% by volume based on the total volume of the photocurable resin composition, and The whisker content is preferably 5 to 30% by volume. When both the solid fine particles and the whiskers are contained, the total content of both is preferably 10 to 75% by volume based on the total volume of the photocurable layer.
The solid fine particles and / or whiskers may or may not be surface-treated with a silane coupling agent, but are preferably surface-treated. When the solid fine particles and / or whiskers are surface-treated with a silane coupling agent, a photocured product having a higher heat distortion temperature, flexural modulus, and mechanical strength can be obtained. As the silane coupling agent in this case, any of silane coupling agents conventionally used for surface treatment of a filler or the like can be used. Preferred silane coupling agents are aminosilane, epoxysilane, vinylsilane, and ( (Meth) acryl silane.
[0055]
As described above, the apparatus and method of the present invention are particularly preferably used in an optical three-dimensional molding technique for producing a three-dimensional molded article using a photocurable resin composition.
However, the optical device of the present invention including the above-described polarization separation element and a liquid crystal drawing mask having a liquid crystal shutter capable of blocking and transmitting light in a minute area has a high light quantity (light intensity) maintenance rate and a single polarization. Because of its excellent characteristics such as easy emission, simplicity, and low cost, it can be effectively used as an optical device in, for example, a projector, a large television, a semiconductor manufacturing device, and the like in addition to the optical three-dimensional modeling.
[0056]
【Example】
Hereinafter, the present invention will be described specifically with reference to Examples and the like, but the present invention is not limited to the following Examples.
[0057]
<< Example 1 >>
(1) The optical three-dimensional printing apparatus shown in FIG. 4 was used.
An ultra-high pressure mercury lamp was used as the light source, and the light intensity at the light emitting means (rod lens) (1) was adjusted to a uniformity of 80%. The polarization splitting element (2a) shown in FIG. 1 (thickness = 5 mm, α ₁ And α ₂ Angle = 45 °, polarization separation plane A ₁ -Polarization separation surface A ₂ [Distance between tip of light emitting means and polarization splitting element (2a) = 30 cm]. A condensing lens (4) (manufactured by Nippon Special Optical Co., Ltd .; Fresnel lens) is disposed at a position 1 cm away from the polarization splitting element (2a), and a liquid crystal drawing mask (3) (pixel number = 640 dots × 480) is disposed immediately below the condenser lens (4). Dot). A projection lens (6) is arranged at a position 45 cm away from the liquid crystal drawing mask (3), and a photocurable resin composition (manufactured by Teijin Seiki Co., Ltd.) is placed at a position 22.5 cm away from the projection lens (6). A molding surface (5) was formed by a conventional method (modeling bath method) using "TSR-754").
[0058]
(2) Using the optical three-dimensional modeling apparatus of (1), light of a shape pattern corresponding to a predetermined mask image formed by the liquid crystal drawing mask (3) is formed on a modeling surface of each layer (5). Irradiation time is 2 seconds, the surface of the photocurable resin composition is irradiated, and the photolithography is performed by adopting a method of laminating the photolithography molding (length × width × thickness = 65 mm × 50 mm × 50 mm). The total time required for modeling was 50 minutes.
The resulting shaped article had good appearance, excellent dimensional accuracy, no curing unevenness, and excellent strength.
(3) In the optical three-dimensional modeling apparatus according to the above (1), the light intensity (illuminance) of a polarized (P-wave) bundle whose polarization direction is aligned with a single vibration direction immediately before being introduced into the liquid crystal drawing mask (3). ) Was measured to be 3 mW / cm ² That is, 46% of the intensity (illuminance) of the light emitted from the light emitting means (1) was maintained.
[0059]
<< Comparative Example 1 >>
(1) Using the same light source and light emitting means (rod lens) (1) as used in Example 1 without using the polarization splitting element (2a) used in Example 1, The same condensing lens (4) as used in Example 1 is disposed at a position 20 cm below the rod lens (1) and the polarizing film is disposed immediately below the condenser lens on both the light introduction side and the light exit side. Liquid crystal drawing mask (number of pixels = 640 dots × 480 dots) was arranged. The same projection lens (6) as that used in Example 1 was arranged at a position 45 cm away from the liquid crystal drawing mask, and used in Example 1 at a position 22.5 cm away from the projection lens (6). A molding surface (5) was formed in the same manner using the same photocurable resin composition as described above.
(2) Using the optical three-dimensional modeling apparatus of (1), a predetermined mask image similar to that in the first embodiment is formed by the liquid crystal drawing mask, and light of a shape pattern corresponding to the mask image is generated by one. Irradiation was performed on the molding surface (5) of each layer, and the operation was repeated to produce a molded article (length × width × thickness = 65 mm × 50 mm × 50 mm) having the same shape and dimensions as in Example 1. In Comparative Example 1, the irradiation time of light required for photocuring the modeling surface of one layer was 6 seconds, and the total modeling time required for manufacturing a molded article was 84 minutes. The required irradiation time was much longer than that, and the molding speed was accordingly much lower than in Example 1.
[0060]
【The invention's effect】
In the case of the present invention, an expensive ultraviolet laser, a fly-eye lens (lens array), an expensive polarization splitting element, a birefringent crystal, or the like is not used, and further, it is indispensable for the above-described conventional optical device. Without using a half-wavelength phase delay element, a very simple device is used to maintain a high light intensity (light energy intensity) of 45% or more while maintaining a single light beam having a single vibration direction. It can be guided to a drawing mask equipped with a liquid crystal shutter in one polarization form, and from small three-dimensional objects to large three-dimensional objects, with extremely good light energy efficiency, high modeling accuracy, dimensional accuracy, and rapid modeling It is possible to produce a high-quality three-dimensional object excellent in mechanical properties, appearance and the like at high speed with high productivity.
In addition, according to this method, since the light intensity (irradiation intensity) of the single polarized light supplied to the drawing mask via the polarization separation element is uniform and the whole is uniform, the objective three-dimensional structure can be made high. The three-dimensional object obtained can be manufactured with high modeling accuracy, and the obtained three-dimensional object is extremely excellent in mechanical properties, appearance, and the like.
In particular, in the present invention, the above-mentioned polarization splitting elements (2a) to (2c) are preferably used as the polarization splitting element because the above-described excellent effects of the present invention can be achieved despite the extremely simple structure. used.
[Brief description of the drawings]
FIG. 1 is a diagram showing an example of a polarization beam splitter used in the present invention.
FIG. 2 is a diagram showing another example of the polarization beam splitter used in the present invention.
FIG. 3 is a diagram showing still another example of the polarization beam splitter used in the present invention.
FIG. 4 is a diagram illustrating an example of an optical three-dimensional modeling apparatus and an optical three-dimensional modeling method of the present invention.
FIG. 5 is a diagram for explaining a polarization direction of light.
FIG. 6 is a diagram illustrating an example of a conventional optical device.
FIG. 7 is a diagram showing another example of a conventional optical device.
[Explanation of symbols]
A ₁ Polarization separation surface
A ₂ Polarization separation surface
A ₃ Polarization separation surface
B Light-shielding surface
1 light source or light emitting means
2 Polarization separation element
2a Polarization separation element
2b Polarization separation element
2c Polarization separation element
3 Liquid crystal drawing mask
4 Condensing lens
5 modeling surface
6 Projection lens

Claims (10)

After forming a light-cured resin layer having a predetermined cross-sectional shape pattern by irradiating light under control through a drawing mask having a liquid crystal shutter on a molding surface made of a photocurable resin composition, the photocured resin One layer of the photocurable resin composition is applied on the layer to form a molding surface, and the molding surface made of the photocurable resin composition is irradiated with light under control via a drawing mask to a predetermined shape. A method of manufacturing a three-dimensional structure by sequentially repeating an operation of further forming a photocured resin layer having a cross-sectional shape pattern until a predetermined three-dimensional structure is formed,
Using a polarization separation element having a polarization separation surface to separate light emitted from the light source or the light emitting unit into two polarized lights whose vibration directions are orthogonal to each other on the polarization separation surface of the polarization separation element;
One of the polarized lights separated by the polarized light separating surface passes through the polarized light separating element and is directed to the drawing mask;
The other polarized light separated by the polarized light separating surface is reflected by the polarized light separating surface and then re-reflected, scattered and / or absorbed so as not to pass through the polarized light separating element;
Irradiating the one polarized light that has passed through the polarization separation element onto a modeling surface made of a photocurable resin composition through a drawing mask having a liquid crystal shutter capable of blocking and transmitting light in a small area, Forming a photocured resin layer having a predetermined cross-sectional pattern corresponding to the mask image of
An optical three-dimensional modeling method characterized by the following. As the polarization splitting element, a polarization splitting element having at least one set of structural parts in which two polarization splitting surfaces A ₁ and A ₂ are arranged to face each other in a V-shaped plane symmetric state is used;
The light emitted from the light source or the light emitting means is separated into two polarized lights whose vibration directions are orthogonal to each other on each of the polarization splitting surfaces A ₁ and A ₂ of the polarization splitting element. by passing directs towards the image drawing mask, the other polarization is reflected by the respective polarization separating surfaces a ₁ and a _2;
Polarization separation surface A ₁ the other polarized light is reflected by the polarization separation surface A ₂ causes re reflecting the other polarized light is reflected by the polarization separation surface A ₂ in directs towards the polarization separation surface A ₂ in by re-reflected by the polarization separation surface a ₁ a and directs the direction of the polarization separation surface a _1, the other polarization is prevented from passing through the polarization separating element;
The optical three-dimensional modeling method according to claim 1, comprising: As a polarization separation element, a structure in which two polarization separation planes A ₁ and A ₂ are arranged to face each other in a V-shaped plane symmetric state and a light shielding surface B is arranged at a position symmetrical to the polarization separation planes A ₁ and A ₂ is defined as 1 Using a polarized light separating element having at least two sets;
The light emitted from the light source or the light emitting means is separated into two polarized lights whose vibration directions are orthogonal to each other on each of the _two polarized light separating surfaces A ₁ and A ₂ of the polarized light separating element, and one of the separated polarized lights is polarized light separation. passed through a device directs towards the drawing mask and the other polarization is reflected by the polarization separation surface a ₁ and a _2;
Reflected again by the light shielding surface B the other polarized light is reflected by the polarization separation surface A ₁ and A ₂ by directing the light shielding surface B, by scattering and / or absorption, the other polarization is polarization separation element Not pass through;
The optical three-dimensional modeling method according to claim 1, comprising: As the polarization separating element, opposite at a predetermined angle to the light shielding surface B with respect to the polarization splitting surface A ₃ as well as arranged in a diagonal direction of the polarization separating plane A ₃ to the traveling direction of the light emitted from the light source or the light emitting means Using a polarized light separating element having at least one set of disposed structural parts;
The light emitted from the light source or the light emitting means, the vibration direction by the polarization separation surface A ₃ is separated into two orthogonal polarization to each other towards the image drawing mask in one polarization separated passes the polarization splitting surface A ₃ directs the, the other polarization is reflected by the polarization separation surface a _3;
Reflected again by the light shielding surface the other polarized light is reflected by the polarization splitting surface A ₃ and directs the light shielding surface B, by scattering and / or absorption, so that the other polarized light does not pass through the polarization separating element To;
The optical three-dimensional modeling method according to claim 1, comprising: 5. The method according to claim 1, wherein the one polarized light that has passed through the polarization splitting element is supplied to a drawing mask through a condensing lens, and light of a predetermined mask image that has passed through the drawing mask is applied to a modeling surface through a projection lens. The optical three-dimensional modeling method according to claim 1. .Light sources or light emitting means;
.Having a polarization separation surface for separating the light emitted from the light source or the light emission means into two polarization lights whose vibration directions are orthogonal to each other, and one of the two polarization lights separated by the polarization separation plane is polarization separation light A polarization splitting element that passes through the element and reflects the other polarized light on the polarization splitting surface and then re-reflects, scatters, and / or absorbs the light so as not to pass through the polarization splitting element;
A drawing mask arranged on the downstream side of the polarization splitting element, the drawing mask including a plurality of minute liquid crystal shutters capable of blocking and transmitting light in a minute area; and
Means for forming a shaped surface made of the photocurable resin composition;
An optical three-dimensional printing apparatus characterized by having: Polarization splitter,
-Two polarization separations that separate the light emitted from the light source or the light emitting means into two polarized lights whose vibration directions are orthogonal to each other, allow one of the two polarized lights to pass, and reflect the other polarized light. A polarization splitting element having at least one set of structural parts in which the planes A ₁ and A ₂ are arranged to face each other in a V-shaped plane symmetric state;
-Two polarization separations that separate the light emitted from the light source or the light emitting means into two polarized lights whose vibration directions are orthogonal to each other, allow one of the two polarized lights to pass, and reflect the other polarized light. A polarization splitting element having at least one set of structural parts in which surfaces A ₁ and A ₂ are opposed to each other in a V-shaped plane symmetric state, and a light-shielding surface B is arranged at a position symmetrical to the polarization splitting surface A ₁ and the polarization splitting surface A ₂ Or
A polarization separation surface A that separates the light emitted from the light source or the light emitting means into two polarized lights whose vibration directions are orthogonal to each other, passes one of the two polarized lights, and reflects the other polarized light. having ₃ light sources or a structure which is opposed at a predetermined angle to the light shielding surface B with respect to the polarization splitting surface a ₃ 1 or more sets as well as arranged in an oblique direction with respect to the traveling direction of the light emitted from the light emitting means Polarization separation element;
The optical three-dimensional modeling device according to claim 6, wherein The optical three-dimensional modeling apparatus according to claim 6, wherein the polarization separation surface of the polarization separation element is arranged at an angle of 40 ° to 50 ° with respect to a traveling direction of light emitted from the light source or the light emitting unit. . It has a polarization separation surface that separates light emitted from the light source or the light emission unit into two polarization lights whose vibration directions are orthogonal to each other, and one of the two polarization lights separated by the polarization separation surface is a polarization separation element. And the other polarized light is reflected by the polarized light separating surface and then re-reflected, scattered, and / or absorbed so as not to pass through the polarized light separating element; and
A drawing mask comprising a plurality of minute liquid crystal shutters disposed downstream of the polarization separation element and capable of blocking and transmitting light in a minute area;
An optical device having:
-Two polarization separations that separate the light emitted from the light source or the light emitting means into two polarized lights whose vibration directions are orthogonal to each other, allow one of the two polarized lights to pass, and reflect the other polarized light. A polarization splitting element having at least one set of structural parts in which the planes A ₁ and A ₂ are arranged to face each other in a V-shaped plane symmetric state;
-Two polarization separations that separate the light emitted from the light source or the light emitting means into two polarized lights whose vibration directions are orthogonal to each other, allow one of the two polarized lights to pass, and reflect the other polarized light. A polarizing beam splitter having at least one pair of structural parts in which the surfaces A ₁ and A ₂ are opposed to each other in a V-shaped plane symmetric state and a light-shielding surface is disposed at a position symmetrical to the polarization separating surface A ₁ and the polarization separating surface A ₂ ; Or
A polarization separation surface A that separates the light emitted from the light source or the light emitting means into two polarized lights whose vibration directions are orthogonal to each other, passes one of the two polarized lights, and reflects the other polarized light. having ₃ light sources or a structure which is opposed at a predetermined angle to the light shielding surface B with respect to the polarization splitting surface a ₃ 1 or more sets as well as arranged in an oblique direction with respect to the traveling direction of the light emitted from the light emitting means Polarization separation element;
An optical device, characterized in that: The optical device according to claim 9, wherein the polarization splitting surface of the polarization splitting element is arranged at an angle of 40 ° to 50 ° with respect to the traveling direction of the light emitted from the light source or the light emitting unit.

Images