WO2009134024A2

WO2009134024A2 - Optical modulated object

Info

Publication number: WO2009134024A2
Application number: PCT/KR2009/001941
Authority: WO
Inventors: Yeon Soo Kim; Do Hyun Kim; In Young Yang; Jin Soo Kim; Deog Jae Jo
Original assignee: Woongjin Chemical Co., Ltd.
Priority date: 2008-04-30
Filing date: 2009-04-15
Publication date: 2009-11-05
Also published as: WO2009134024A3; TW200944866A; KR20090114708A

Abstract

The present invention relates to an optical modulated object, and more particularly, to an optical modulated object for having light, being incident on its base material, modulated into light of a desired form such that it is appropriate for optical usage. In the optical modulated object of the present invention, the birefringent polymer is disposed within an isotropic base material. Thus, when light is irradiated to the base material, a birefringent interface is formed between the isotropic base material and the birefringent polymer due to a difference in the optical property. Accordingly, luminance can be improved and consumption power can be saved by changing the property of irradiated light, if appropriate, or integrating, scattering, reflecting or refracting light.

Description

OPTICAL MODULATED OBJECT

The present invention relates to an optical modulated object, and more particularly, to an optical modulated object for having light, being incident on its base material, modulated into light of a desired form such that it is appropriate for optical usage.

An optical modulated object is comprised of an inclusion dispersed in a consecutive matrix and has been known in the related technical field. The optical modulated object can be given a certain range of reflectivity and permeability by controlling the properties of the inclusion. The properties may include the size of the inclusion with respect to a wavelength within the object, the form and arrangement of the inclusion, the volume ratio of the inclusion and the degree of mismatching in the refractive index with the consecutive matrix (base material) according to three orthogonal axes of the object.

A typical absorbing polarizer comprises inorganic bar-shaped chains, comprising optical absorbing iodine arranged within a polymer matrix, in an inclusion fashion. This kind of a film has a tendency that it absorbs light, which is polarized along its electric field vectors arranged in parallel to the bar-shaped iodine chains, and transmits the polarized light perpendicular to the bar. The iodine chain has two kinds of dimensions and more whose wavelength is smaller than that of a visible ray and has a large number of cubic chains in the optical wavelength. Thus, the optical property of the optical modulated object generally looks like a mirror face (specular), and diffusion transmission through the optical modulated object or diffusion reflection from a surface of the optical modulated object are very few. Like most commercial optical modulated objects, such an optical modulated object is based on selective absorption of polarized light.

Optical modulated objects filled with inorganic inclusions with a variety of characteristics can provide different optical permeability and reflectivity. For example, there is an example in which a coated mica thin section having two or more dimensions, which are greater than the wavelength of a visible region, is included in a polymer film and paint and then metallic glass is assigned. Strong directional dependency against the reflection aspects can be provided by controlling the thin section to exist in the film plane.

It is possible to fabricate a safety screen, which has great reflectivity from a specific viewing angle and is transparent from a different viewing angle, based on the above effect. Further, the evidence of reflection (tampering) can also be provided by including a large-sized thin section, having a chromogenic action (selective regular reflection) dependent on an alignment state toward incident light, in the film. In this usage, the entire thin sections within the film need to be aligned similarly to each other.

However, the optical film fabricated using polymers filled with inorganic inclusion has several shortcomings. Typically, adhesion between inorganic particles and a polymer matrix is poor. Accordingly, the optical property of an optical modulated object is deteriorated when experiencing stress or deformation perpendicularly to the matrix. This may damage coupling between the matrix and the inclusion and also break the rigid inorganic inclusion. In addition, a fabrication method becomes complicated since further consideration must be taken as to a processing step in order to align the inorganic inclusion.

However, more fundamentally, there was a problem in that optical modulation efficiency was low since both the optical property of the matrix constituting the conventional optical modulated object and the optical property of the inclusion included in the matrix are optically isotropic.

Accordingly, the present invention has been made in view of the above problems occurring in the prior art, and an object of the present invention is to provide an optical modulated object in which birefringent polymers having different optical properties from a base material are arranged within the base material, thereby maximizing optical modulation efficiency.

To achieve the above object, an optical modulated object according to an aspect of the present invention has a birefringent polymer disposed within a base material.

Here, the base material is isotropic and may preferably use any one or more of polyethylene naphthalate (PEN), copolyethylene naphthalate (co-PEN), polyethylene terephthalate (PET), copolyethylene terephthalate (co-PET), polycarbonate (PC), polycarbonate (PC) alloy, polystyrene (PS), heat-resistant polystyrene (PS), polymethyl methacrylate (PMMA), polybutylene terephthalate (PBT), polypropylene (PP), polyethylene (PE), acrylonitrile butadiene styrene (ABS), polyurethane (PU), polyimide (PI), poly vinyl chloride (PVC), styrene acrylonitrile mixture (SAN), ethylene vinyl acetate (EVA), polyamide (PA), polyacetal (POM), phenol, epoxy (EP), urea (UF), melanin (MF), non-saturated polyester (UP), silicon (SI), elastomers and cyclo olefin polymer.

The birefringent polymer may preferably use the same material as that of the base material or substance having birefrigence. Preferably, the birefringent polymer may be disposed in plural numbers within the base material in one direction. More preferably, the birefringent polymer may be disposed within the base material vertically to a light source.

The birefringent polymer may be preferably comprised in a volume of 1 to 90% based on the total optical modulated object. The birefringent polymer may be disposed 500 to 1010 in number with respect to the optical modulated object 1㎤.

The optical modulated object may preferably comprise a structured surface layer which is formed in the opposite direction of light source. The structured surface layer may be a prism shape, an lenticular shape, a convex lens shape or a micro lens shape. The shapes may have regularity or irregularity. Further, the birefringent polymer may be disposed or not disposed on the structured surface layer.

Light irradiated from a light source transmitS through the optical modulated object, and the transmitted light may be natural light or polarized light. The birefringent polymer may be disposed in a stack form or dispersed within the base material.

The birefringent polymer may be preferably a birefringent fiber. The birefringent fiber may be preferably an optical modulation fiber comprising an anisotropic core fiber. More preferably, the optical modulation fiber may comprise an anisotropic core fiber disposed within a filler.

The filler may be preferably isotropic. More preferably, the filler may be the same material as that of the base material and may use substance with isotropy. The anisotropic core fiber may preferably use the same material as that of the base material or substance with anisotropy.

A difference in a refractive index of the filler and the anisotropic core fiber with respect to two axial directions may be preferably 0.03 or less, and a difference in a refractive index of the filler and the anisotropic core fiber with respect to the remaining one axial direction may be 0.05 or more.

The anisotropic core fiber may preferably comprise a fiber outer cover surrounding a fiber core.

The optical modulated object may preferably comprise a plurality of optical modulation fibers having different cross sections. One or more of the filler and the anisotropic core fiber may comprise birefringent polymer substance.

One or more of the polymer optical modulation fiber and the anisotropic core fiber may be preferably drawn in a length direction.

The optical modulation fiber may be preferably a sheath-core conjugate fiber. Here, the sheath-core conjugate fiber has a core portion correspond to the anisotropic core fiber and a sheath portion correspond to the filler.

The optical modulation fiber may be preferably an island-in-the-sea yarn, the anisotropic core fiber may correspond to an island portion of the island-in-the-sea yarn, and the filler may correspond to a sea portion of the island-in-the-sea yarn. In this case, the sea portion and the island portion may preferably have different refractive indices in at least one direction. More preferably, a difference in a refractive index of the sea portion and the island portion with respect to two axial directions may be 0.03 or less, and a difference in a refractive index of the sea portion and the island portion with respect to the remaining one axial direction may be 0.05 or more.

An area ratio of the sea portion and the island portion may be preferably in the range of 2 : 8 to 8 : 2.

The island portion may be preferably disposed in plural numbers within the island-in-the-sea yarn. Preferably, the sea portion may be isotropic, and the island portion may be anisotropic.

A polymer used in the island-in-the-sea yarn may preferably use one or more selected from polyethylene naphthalate (PEN), copolyethylene naphthalate (co-PEN), polyethylene terephthalate (PET), copolyethylene terephthalate (co-PET), polycarbonate (PC), polycarbonate (PC) alloy, polystyrene (PS), heat-resistant polystyrene (PS), polymethyl methacrylate (PMMA), polybutylene terephthalate (PBT), polypropylene (PP), polyethylene (PE), acrylonitrile butadiene styrene (ABS), polyurethane (PU), polyimide (PI), poly vinyl chloride (PVC), styrene acrylonitrile mixture (SAN), ethylene vinyl acetate (EVA), polyamide (PA), polyacetal (POM), phenol, epoxy (EP), urea (UF), melanin (MF), non-saturated polyester (UP), silicon (SI), elastomers and cyclo olefin polymer, and the one or more polymers may be used as the sea portion and the island portion, respectively.

The island-in-the-sea yarn may preferably have a thickness of 0.3 to 20 denier. 500 to 4,000,000 number/㎤ of the island-in-the-sea yarns may be preferably disposed within the optical modulated object.

A cross section of the island-in-the-sea yarn may preferably be non-circular, possibly, circular or oval.

A cross section of the island-in-the-sea yarn may preferably have a non-circular section.

A refractive index of the sea portion may be preferably identical to that of the base material of the optical modulation object.

The island-in-the-sea yarn may be preferably weaved in wefts and warps or may have a beam shape without wefts. Further, any one of the weft and warp may be the island-in-the-sea yarn, and the other one may be an isotropic fiber. The weft or the warp may be preferably formed by 1 to 200 strands of gathered island-in-the-sea yarns.

The birefringent fiber may be preferably a conjugate yarn comprised of isotropic filling portions and anisotropic conjugate portions partitioned by the isotropic filling portion. In this case, a cross section of the conjugate yarn may be a non-circular section. The anisotropic conjugate portion may be preferably formed in plural numbers.

A plurality of the isotropic filling portions may be preferably parallel to each other, or cross each other within the conjugate yarn.

An optical modulated object according to another aspect of the present invention comprises a birefringent optical modulation fiber disposed within a base material, wherein the birefringent optical modulation fiber comprises an anisotropic core fiber disposed within a filler, a refractive index of the anisotropic core fiber may be different from that of the filler in at least one axial direction, and a plurality of birefringent interface may be formed between the anisotropic core fiber and the filler.

The base material and the filler may be preferably isotropic.

A difference in a refractive index of the anisotropic core fiber and the filler in two axial directions may be preferably 0.03 or less, and a difference in a refractive index of the anisotropic core fiber and the filler in the remaining one axial direction may be 0.05 or more.

In an optical modulated object according to another aspect of the present invention, assuming that a refractive index of a base material in a x-axis direction may be nX1, a refractive index of the base material in a y-axis direction may be nY1 and a refractive index of the base material in a z-axis direction of may be nZ1, and a refractive index of a birefringent optical modulation fiber in the x-axis direction may be nX2, a refractive index of the birefringent optical modulation fiber in the y-axis direction may be nY2 and a refractive index of the birefringent optical modulation fiber in the z-axis direction may be nZ2, at least one of the refractive indices of the base material in the X, Y and Z-axis directions may be preferably identical to at least one of the refractive indices of the birefringent optical modulation fiber in the X, Y and Z-axis directions.

The refractive index may be preferably nX2 > nY2 = nZ2.

The birefringent optical modulation fiber may preferably comprise an anisotropic core fiber disposed within a filler.

Assuming that a refractive index of the anisotropic core fiber in a x-axis direction may be nX2, a refractive index of the anisotropic core fiber in a y-axis direction may be nY2 and a refractive index of the anisotropic core fiber in a z-axis direction may be nZ2, and a refractive index of the filler in the x-axis direction may be nX3, a refractive index of the filler in a y-axis direction may be nY3 and a refractive index of the filler in a z-axis direction may be nZ3, an absolute value of a difference in the refractive index between the nX2 and nX3 or the nY2 and nY3 may be 0.05 or more. In this case, the absolute value in a difference in the refractive index between the nZ2 and nZ3 may be less than 0.03.

The above-described optical modulated object of the present invention may be preferably utilized as a luminance-enhanced film included in a liquid crystal display.

The terminologies used in the specification are defined in short.

What a polymer has birefrigence means, not otherwise described, that, in the case in which light is irradiated on polymers having different refractive indices according to directions, the light incident on the polymers are refracted as two lights with different directions.

The terminology 'isotropy' means that when light passes through an object, it has a constant refractive index irrespective of its direction.

The terminology 'anisotropy' means that the optical properties of an object differ according to the direction of light. An anisotropic object has birefrigence and opposites to isotropy.

The terminology 'optical modulation' means that irradiated light is reflected, refracted, scattered, or the intensity, cycle of wave motion or property of light is changed.

In accordance with the optical modulated object of the present invention, in the case in which birefringent polymers are disposed within an isotropic base material and light is irradiated on the base material, a birefringent interface is formed between the isotropic base material and the birefringent polymers due to a difference in the optical properties. Accordingly, luminance can be improved and consumption power can be saved by changing the property of irradiated light or integrating, scattering, reflecting or refracting the light, if appropriate.

Furthermore, in the case in which the optical modulated object of the present invention is used as a luminance-enhanced film, a layer is formed to include birefringent island-in-the-sea yarns within a base material unlike a conventional stacked luminance-enhanced film. Accordingly, the optical modulated object of the present invention can have an excellent luminance-enhancing effect while not forming a number of layers. Furthermore, since several hundreds of layers are not stacked in one film, fabrication is very convenient and a cost-saving effect in production cost is excellent.

Further objects and advantages of the invention can be more fully understood from the following detailed description taken in conjunction with the accompanying drawings in which:

FIG. 1 is a schematic view of a cutaway cross-sectional view of an optical modulated object in accordance with an embodiment of the present invention;

FIG. 2 is a schematic view of a cutaway cross-sectional view of an optical modulated object in accordance with another embodiment of the present invention;

FIGS. 3 to 8 are cross-sectional views of structured surfaces of the optical modulated object in accordance with another embodiment of the present invention;

FIGS. 9 to 11 are cross-sectional views of birefringent optical modulation fibers in accordance with an embodiment of the present invention;

FIGS. 12 to 20 are cross-sectional views of birefringent optical modulation fibers in accordance with another embodiment of the present invention;

FIG. 21 is a cross-sectional view of the path of light incident on a birefringent island-in-the-sea yarn of the present invention;

FIGS. 22 to 23 show the arrangements of the birefringent optical modulation fibers in accordance with an embodiment of the present invention;

FIG. 24 to 28 are cross-sectional views of the birefringent optical modulation fibers in accordance with an embodiment of the present invention; and

FIG. 29 is a schematic view of a cutaway cross-sectional view of an optical modulated object in accordance with still another embodiment of the present invention.

100, 200: base material 110, 210: birefringent polymer

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

In a conventional optical modulated object, both the optical property of a matrix constituting the optical modulated object and the optical property of an inclusion inserted into the matrix have optical isotropy, which makes irradiated light not modulated in various forms. Accordingly, the conventional optical modulated object was problematic in that it had low optical modulation efficiency and could not modulate light into light of a desired form.

In view of the problems, in the optical modulated object of the present invention, birefringent polymers are disposed within a base material, and light incident on the optical modulated object from the outside is reflected, scattered and refracted at a birefringent interface, that is, an interface between the birefringent polymers and the isotropic base material, so the light is optically modulated. In particular, light irradiated from an external light source is largely divided into S-polarized light and P-polarized light. In the case in which only a specific polarized light is desired, the P-polarized light passes through the optical modulated object without being influenced by the birefringent interface. However, the S-polarized light is refracted, scattered and reflected at the birefringent interface and then modulated into a wavelength of a random form, that is, S-polarized light or P-polarized light. If the modulated light is reflected and again irradiated on the optical modulated object, the P-polarized light passes through the optical modulated object and the S-polarized light is scattered or reflected again. If this process is repeated, a desired P-polarized light can be obtained.

FIG. 1 is a schematic view of a cutaway cross-sectional view of an optical modulated object in accordance with an embodiment of the present invention. More specifically, the optical modulated object has polymers 110, having birefrigence, freely arranged within a base material 100 having isotropy. Materials of the base material 100 that can be used at this time include thermoplastic and thermosetting polymers that can transmit an optical wavelength of a target range. The base material 100 that is preferably appropriate may be amorphous or merocrystalline and may comprise a single polymer, a copolymer or a blend thereof. More specifically, poly(carbonate) (PC); syndiotactic and isotacticpoly(styrene) (PS); alkyl styrene; alkyl such as poly(methyl methacrylate) (PMMA) and PMMA copolymer, aromatic and aliphatic pendent (meth)acrylate; ethoxide and propoxide (meth)acrylate; multi-functional (meth)acrylate; acrylated epoxy; epoxy; and other ethylene unsaturated substance; ring-shaped olefin and ring-shaped olefin copolymer; acrylonitrile butadiene styrene (ABS); styrene acrylonitrile copolymer (SAN); epoxy; poly(vinyl cyclohexene); PMMA/poly(vinyl fluoride) blend; poly(phenylene oxide) alloy; styrene block copolymer; polyimide; polysulfone; poly(vinyl chloride); poly(dimethylsiloxane) (PDMS); polyurethane; unsaturated polyester; polyethylene; poly(propylene) (PP); poly(alkane terephthalate), for example, poly(ethylene terephthalate) (PET); poly(alkane naphthalate), for example, poly(etylene naphthalate) (PEN); polyamide; ionomer; vinyl acetate/polyethylene copolymer; cellulose acetate; cellulose acetate butyrate; fluoro polymer; poly(styrene)-poly(ethylene) copolymer; PET and PEN copolymer as well as polyolefin PET and PEN; and poly(carbonate)/aliphatic PET blend may be used. More preferably, PEN, co-PEN, polyethylene terephthalate (PET), polycarbonate (PC), polycarbonate (PC) alloy, polystyrene (PS), heat-resistant polystyrene (PS), polymethyl methacrylate (PMMA), polybutylene terephthalate (PBT), polypropylene (PP), polyethylene (PE), acrylonitrile butadiene styrene (ABS), polyurethane (PU), polyimide (PI), poly vinyl chloride (PVC), styrene acrylonitrile mixture (SAN), ethylene vinyl acetate (EVA), polyamide (PA), polyacetal (POM), phenol, epoxy (EP), urea.melanin (UF.MF), non-saturated polyester (UP), silicon (SI), elastomers, cyclo olefin polymer (COP, ZEON Co. (Japan), JSR Co. (Japan)), either alone or in combination thereof, may be used. Furthermore, the base material may also contain additives, such as an antioxidant, a light stabilizer, a heat stabilizer, a lubricant, a dispersing agent, a UV absorber, white pigment, and a fluorescent whitening agent, unless they do not damage the above physical properties.

The birefringent polymers 110 may preferably have optically birefrigence and may employ material with excellent optical transmittance. The birefringent polymers 110 preferably have the same material as that of the base material, but may employ material whose optical property is birefringent. For example, the base material 100 may employ isotropy co-PEN, and the birefringent polymers 110 may employ PEN with birefrigence. Both the base material 100 and the birefringent polymers 110 may employ resin having only a different optical property. Meanwhile, a method of changing the isotropy material to birefringent material has typically been known. For example, when being oriented under an appropriate temperature condition, the polymer molecules are oriented and have its material become birefringent.

A plurality of the birefringent polymer may be drawn and arranged within the base material in one direction.

FIG. 2 is a schematic view of a cutaway cross-sectional view of an optical modulated object in accordance with another embodiment of the present invention. Birefringent polymers 210 are disposed in one direction within a base material 200. More preferably, the birefringent polymers 210 may be disposed within the base material vertically to a light source. In this case, optical modulation efficiency is maximized. Meanwhile, the birefringent polymers 210 arranged in series may be dispersed to each other and disposed, if appropriate, and between-the birefringent polymers 210 may be brought in contact with each other or separated from each other. In the case in which between-the birefringent polymers 210 brought in contact with each other, the birefringent polymers 210 may be closely stacked arranged in layers.

Furthermore, for example, if three or more birefringent polymers having different diameters and circular are arranged, a triangle, which is obtained by interconnecting the center of three circles being adjacent to each other in the cross section perpendicular to their longitudinal directions becomes a scalene. Further, in the cross section being perpendicular to the longitudinal directions of the birefringent polymers (cylindrical body), the cylindrical bodies are arranged such that the circles in a first layer and the circles in a second layer are brought in contact with each other, the circles in the second layer and the circles in a third layer are brought in contact with each other, and the circles in layers below the third layer, which are sequentially brought in contact with each other. However, with respect to the respective birefringent polymers, a condition 「each birefringent polymer is brought in contact with two or more birefringent polymers, which are brought in contact with each other on the side of the circular cylinder, on the sides of their circular cylinders 」 has only to be fulfilled. In this range, for example, a construction in which the circles in the first layer and the circles in the second layer are brought in contact with each other, the circles in the second layer and the circles in the third layer are spaced apart from each other with a support medium intervened therebetween, and the circles in the third layer and the circles in the fourth layer are brought in contact with each other is also possible.

It is preferred that a triangle, which connects the centers of three circles being directly brought in contact with each other in the cross section vertical to the long axial direction of the birefringent polymer, have at least the lengths of two sides being approximately identical. In particular, it is preferred that the lengths of three sides of the triangle be approximately identical. Further, in relation to the stack state of the birefringent polymers in a thickness direction of the optical modulated object, it is preferred that the plurality of layers be stacked so that they are sequentially brought in contact with each other. Further, it is more preferred that birefringent polymers comprised of a cylindrical body having approximately the same diameter be closely filled.

Accordingly, in this more preferred form, the diameters of the circles of the plurality of birefringent polymers in the cross sections vertical to the long axial direction have approximately the same cylindrical body, and birefringent polymers located inwardly than the outermost surface layer in the cross section are brought in contact with birefringent bodies, that is, six different cylindrical bodies on the side of the circular cylinder.

Meanwhile, it is preferably advantageous that the birefringent polymer has the volume of 1% to 90% with respect to the optical modulated object 1㎤. If the volume of the birefringent polymer is 1% or less, an optical modulation effect is very small. If the volume of the birefringent polymer is 90% or more, problems may arise because the amount of scattering due to the birefringent interface is increased and optical loss happens.

Furthermore, 500 to 1010 birefringent polymers may be disposed within the optical modulated object 1 ㎤. The diameter of the cross section of an anisotropic core fiber within the birefringent polymer can also have a significant effect on optical modulation. If the diameter of the cross section of each anisotropic core fiber of the birefringent polymer is smaller than an optical wavelength, refraction, scattering and reflection effects are decreased and therefore optical modulation is rarely generated. If the diameter of the cross section of the anisotropic core fiber is too large, light experiences regular reflection from a surface of the polymer and diffusion in other directions is very less. The diameter of the cross section of an aligned anisotropic core fiber may change according to a target use of an optical object. For example, the diameter of a fiber may be greatly dependent on the wavelength of electromagnetic ray, which is important in a specific usage, and fibers with different diameters are required in order to reflect, scatter or transmit a visible ray, ultraviolet rays, infrared rays and microwaves.

The optical modulated object may preferably comprise a structured surface layer according to its purpose. FIGS. 3 to 8 are cross-sectional views of structured surfaces of the optical modulated object in accordance with another embodiment of the present invention. In FIG. 3, an incident surface and an outgoing surface of an optical modulated object can be parallel to light irradiated from a light source 300a. In this case, as shown in FIG. 4, birefringent polymers 321b, which are located (adjacent to) over a light source 300b, can be disposed closely, and birefringent polymers 320b, which are located far from the light source 300b, can be disposed brokenly.

The structured surface layer can be formed on a surface from which light is output. The structured surface layer can have a prism shape, a lenticular shape or a convex lens shape. More specifically, in FIG. 5, a surface from which light is output on an optical modulated object can have a curved type surface 330c having a convex lens shape. The curved type surface 330c can focus or defocus light transmitting the surface. Further, as shown in FIG. 6, a prism pattern 330d can be formed in a light outgoing surface. In this case, birefringent polymers 320d may not be formed in a structured surface layer 330d as shown in FIG. 6, birefringent polymers 320e may be formed both in a base material and a surface layer 330e as shown in FIG. 7, or birefringent polymers 320f may be formed only in a structured surface layer 330f as shown in FIG. 8.

Concave-convex portions can be formed at least one surface of an optical modulation object through Matt treatment and given a scratch-resistant property. More preferably, the Matt treatment can be performed on the other surface of the structured surface under the condition that an adverse effect does not occur in the effects of the present invention.

Meanwhile, light transmitting the light source can include both natural light and polarized light, and several materials having birefrigence can be used as birefringent polymers. However, it is preferred that the birefringent polymers are solid from a viewpoint of orientation or stability, durability, etc. of a cross section shape.

Consequently, in a first embodiment of the present invention, birefringent polymers are disposed within an isotropic base material in order for light to be modulated efficiently through a birefringent interface formed between the base material and the birefringent polymers.

In a second embodiment of the present invention, the birefringent polymer is preferably a birefringent fiber. More preferably, the birefringent fiber is preferably an optical modulation fiber including an anisotropic core fiber. More preferably, the optical modulation fiber can include an anisotropic core fiber disposed within an isotropic filler.

The first embodiment of the present invention discloses a technical spirit in which a number of birefringent polymers are disposed within an isotropic base material so that light is modulated according to a desired object through a birefringent interface between the isotropic base material and the birefringent polymers. However, in the case in which the optical modulation fiber comprising the anisotropic core fiber disposed within the filler is used as the above birefringent polymer, an optical modulation effect between the anisotropic core fiber and the isotropic filler within the optical modulation fiber can be expected as well as an optical modulation effect between the birefringent optical modulation fiber and the base material, that is, the effect of the first embodiment. Accordingly, optical modulation efficiency can be improved significantly.

The filler applicable to the present invention can employ all materials of the above base material, which have optically isotropy and, more preferably, have been described in the first embodiment. Meanwhile, the anisotropic core fiber can employ all the base materials that have been described in the birefringent polymers. Accordingly, for example, PEN having anisotropy can be used as the core fiber, and co-PEN having isotropy can be used as the filler.

Meanwhile, the degree of substantial match or mismatch of the refractive index according to X, Y and Z axes on the space of the isotropic filler and the anisotropic core fiber has an effect on the degree of scattering of a ray of light that is polarized according to the corresponding axes. In general, scattering power is changed in proportion to the square of refractive index mismatch. Accordingly, as the degree of mismatch of the refractive index according to a specific axis is increased, a ray of light polarized according to the corresponding axis is scattered more strongly. On the contrary, when mismatch according to a specific axis is small, a ray of light polarized according to the corresponding axis is scattered less. In the case in which the refractive index of an isotropic filler is substantially identical to that of anisotropic or birefringent substance according to a specific axis, incident light that is polarized by an electric field parallel to the axis is not scattered irrespective of the size, shape and density of a portion of the birefringent substance, but can pass through a fiber. Furthermore, in the case in which the refractive index of an isotropic filler is substantially identical to that of anisotropic or birefringent substance according to a specific axis, a ray of light is not substantially scattered, but pass through an object. In the present invention, in the refractive indices of the filler and the anisotropic core fiber, when a difference in the refractive index with respect to two axial directions is preferably 0.03 or less and a difference in the refractive index with respect to the remaining one axial direction is 0.05 or more, the highest optical modulation efficiency is obtained.

More specifically, assuming that the refractive index of a base material in a x-axis direction is nX1, the refractive index of the base material in a y-axis direction is nY1 and the refractive index of the base material in a z-axis direction of is nZ1, and the refractive index of a birefringent optical modulation fiber in the x-axis direction is nX2, the refractive index of the birefringent optical modulation fiber in the y-axis direction is nY2 and the refractive index of the birefringent optical modulation fiber in the z-axis direction is nZ2, it is preferred that at least one of the refractive indices of the base material in the X, Y and Z-axis directions be identical to at least one of the refractive indices of the birefringent optical modulation fiber in the X, Y and Z-axis directions. In the case in which the birefringent optical modulation fiber is drawn in the x-axis direction, it is advantageous to increase optical modulation efficiency when the refractive index be nX2 > nY2 = nZ2. Through this, straight-line polarized light, which is vibrated in a direction in which the refractive index of the optical modulation fiber is identical to that of the base material, is mostly transparent, but straight-line polarized light, which is vibrated in a direction in which the refractive index of the optical modulation fiber is not identical to that of the base material, is reflected from an interface between a birefringent body and a support medium, so that polarized light resolving power can be generated. This principle is applied not only at the interface of a base material and a birefringent fiber, but also at the interface of an anisotropic core fiber and an isotropic filler within a birefringent fiber.

Furthermore, the birefringent optical modulation fiber may preferably comprise an anisotropic core fiber disposed within a filler. Assuming that the refractive index of the anisotropic core fiber in a x-axis direction is nX2, the refractive index of the anisotropic core fiber in a y-axis direction is nY2 and the refractive index of the anisotropic core fiber in a z-axis direction is nZ2, and the refractive index of the filler in a x-axis direction is nX3, the refractive index of the filler in a y-axis direction is nY3 and the refractive index of the filler in a z-axis direction is nZ3, an absolute value of the difference in the refractive index between nX2 and nX3 may be 0.05 or more. In this case, an absolute value of the difference in the refractive index between nZ2 and nZ3 may be less than 0.03. More preferably, in the case in which the optical modulation fiber is drawn in the x-axis direction, it is advantageous to increase optical modulation efficiency when the absolute value of the difference in the refractive index between nX2 and nX3 is 0.1 or more and the absolute value of the difference in the refractive index between nY2 and nY3 and nZ2 and nZ3 is less than 0.03. Meanwhile, in the case in which the optical modulation fiber is drawn in the x-axis direction, it is advantageous when the difference in the refractive index in the X axis is greater and the difference in the refractive index in other axes is smaller, preferably, identical.

Consequently, a birefringent interface can be formed between a base material and a birefringent fiber and between an anisotropic core fiber within a birefringent fiber and a filler. In this case, optical modulation efficiency can be increased significantly as compared to a case where a birefringent interface is formed only between the base material and the birefringent fiber.

The anisotropic core fiber may preferably comprise a fiber outer cover surrounding the fiber core, the optical modulated object may preferably comprise a plurality of optical modulation fibers with different traverse sections, and one or more of the filler and the anisotropic core fiber may comprise birefringent polymer substance (for example, birefringent cholesteric). Furthermore, one or more of the optical modulation fiber and the anisotropic core fiber may be preferably drawn in a length direction.

As one of the preferred embodiment aspects of the optical modulation fiber, the optical modulation fiber may be a sheath-core conjugate fiber. In this case, the core portion of the sheath-core conjugate fiber corresponds to the anisotropic core fiber, and the sheath portion thereof corresponds to the filler.

More specifically, FIGS. 9 to 11 are cross-sectional views of birefringent optical modulation fibers in accordance with an embodiment of the present invention. In FIG. 9, a core portion 410a corresponds to the anisotropic core fiber, and a sheath portion 400a corresponds to the filler. Further, as shown in FIG. 10, the traverse section of the anisotropic core fiber may be polygonal, such as a triangle, not a circular or oval shape. In addition, as shown in FIG. 11, the sheath-core conjugate fiber may form a concentric circle. Here, in the case in which an anisotropic core fiber 410c/a filler 401c/an anisotropic core fiber 411c/a filler 400c are sequentially disposed beginning from the concentric portion or vice versa, the number of birefringent interfaces is increased as many as the number of boundaries of the anisotropic core fiber and the filler. As a result, an optical modulation effect can be increased significantly as compared to a case where only one concentric circle exists (only one anisotropic core fiber exists).

As another of the preferred embodiment aspects of the optical modulation fiber, the optical modulation fiber may be an island-in-the-sea yarn. In this case, the anisotropic core fiber corresponds to an island portion of the island-in-the-sea yarn, and the filler corresponds to the sea portion of the island-in-the-sea yarn.

In other words, the optical modulated object includes a birefringent optical modulation fiber, comprising an anisotropic core fiber disposed within the filler, within a base material. The anisotropic core fiber has a refractive index different from that of the filler in at least one axial direction, and a plurality of birefringent interfaces is formed between the anisotropic core fiber and the filler. At this time, the base material is preferably isotropic, and the filler is also isotropic.

In this case, the sea portion and the island portion preferably have different refractive indices in at least one direction. More preferably, a difference in the refractive index of the sea portion and the island portion with respect to two axial directions may be 0.03 or less, and a difference in the refractive index of the sea portion and the island portion with respect to the remaining one axial direction may be 0.05 or more.

In the case in which an island-in-the-sea yarn is used as the optical modulation fiber, optical modulation efficiency can be improved significantly as compared to a case where the sheath-core conjugate fiber is used. This is because the island-in-the-sea yarn has a very large number of the island portions corresponding to the anisotropic core fiber and therefore form great many birefringent interfaces together with the isotropic sea portion corresponding to the filler. For example, when 10 island portions exist within the island-in-the-sea yarn, externally irradiated light undergoes at least ten times of optical modulation.

Furthermore, in the case in which a conjugate yarn is formed by twisting several pieces or several tens of pieces of the island-in-the-sea yarns, for example, 10 island-in-the-sea yarns are twisted to form one conjugate fiber, 100 birefringent interfaces exist in the conjugate yarn and 100 or more optical modulations can be generated. Furthermore, in the case of several pieces of threaded island-in-the-sea yarns, for example, when 10 pieces of island-in-the-sea yarns are fabricated, 100 birefringent interfaces exist in the conjugate yarn and 100 or more optical modulations can be generated. This island-in-the-sea yarn of the present invention can be fabricated using a co-extrusion method, etc., but not limited thereto.

Accordingly, while in a typical island-in-the-sea yarn, the island portion remaining after eluting the sea portion is used as an ultra-fine yarn irrespective of birefrigence, the sea portion of the island-in-the-sea yarn is not eluted, and the island-in-the-sea yarn having a sea portion and an island portion with a different optical property is used in itself in the present invention.

The traverse section of the island-in-the-sea yarn in a length direction may have any shape according to its purpose. The island-in-the-sea yarn may also have a circular or non-circular section such as oval, polygonal and non-circular shape of which the degree of non-circularity is 0 to 100. Likewise, the traverse section of the island portion of the island-in-the-sea yarn may have any kind of shapes and may have a circular or non-circular section such as, oval, polygonal and non-circular shape of which the degree of non-circularity is 0 to 100.

FIGS. 12 to 20 are cross-sectional views of birefringent optical modulation fibers in accordance with another embodiment of the present invention. As can be seen from FIGS. 12 to 20, in the present invention, the shape, size, number and arrangement of the island portions may be controlled efficiently according to its optical modulation purpose. FIG. 12 is a cross-sectional view of a typical island-in-the-sea yarn in which approximately circular island portions 520a are partitioned by a sea portion 510a. FIG. 13 is a cross-sectional view of an island-in-the-sea yarn in which the area of a sea portion 510b is larger than that of an island portion 520b. FIG. 14 is a cross-sectional view of an island-in-the-sea yarn in which the shape of an island-in-the-sea yarn has an oval shape. In FIG. 15, an island portion 520d has an oval shape and the island portions are arranged in zigzags. Furthermore, the traverse section of the island-in-the-sea yarn has a rectangular structure, but may have a polygonal structure or a non-circular section.

As illustrated in FIGS. 16 and 17, island portions may be located at the center of an island-in-the-sea yarn or a sea portion may not be located at the center of the island-in-the-sea yarn.

In some embodiment aspects, the island portions may not have the same size. For example, as illustrated in FIGS. 18 and 19, the island-in-the-sea yarn may comprise island portions 520g having a different size of traverse sections. In this specific embodiment aspect, any one (520g) of the island portions may have a relatively larger traverse section than that of the other (521g) of the island portions. The sea portion may correspond to two or more groups of different sizes and may have a substantially different size. Furthermore, as shown in FIG. 20, a birefringent and/or isotropic sheath 530i may be added to an island portion 520i.

Meanwhile, light that transmits a birefringent island-in-the-sea yarn within a base material can be optically modulated at a birefringent interface as described above. More specifically, FIG. 21 is a cross-sectional view of the path of light incident on a birefringent island-in-the-sea yarn of the present invention. In this case, a P wave (solid line) transmits the birefringent island-in-the-sea yarn without being influenced by the birefringent interface, i.e., an interface between a base material and a birefringent island-in-the-sea yarn and an interface between an island portion and a sea portion within the birefringent island-in-the-sea yarn, but S waves (dotted line) are optically modulated under the influence of the birefringent interface, i.e., the boundary between the base material and the birefringent island-in-the-sea yarn and/or the boundary between the island portion and the sea portion within the birefringent island-in-the-sea yarn. Consequently, most of the S waves return back to a light source through optical modulations such as reflection, scattering or refraction. The returned S waves become S waves or P waves after being reflected and then pass through an optical modulation film. Accordingly, if the birefringent island-in-the-sea yarn is used as described above, luminance-enhancement efficiency is excellent as compared to a case where a typical birefringent fiber is used. The birefringent island-in-the-sea yarn also includes the island portion and the sea portion with different optical properties. Accordingly, a case where the birefringent interface can be formed within the island-in-the-sea yarn can have significant optical modulation efficiency as compared to a case where the birefringent interface is not formed within the island-in-the-sea yarn.

Meanwhile, preferably, the island portion may be disposed in plural numbers within the island-in-the-sea yarn, and the area ratio of the sea portion and the island portion may be preferably 2 : 8 to 8 : 2. When eight or more island portions exist in one island-in-the-sea yarn, it is advantageous to maximize an optical modulation effect. The island-in-the-sea yarn may preferably have a thickness of 0.3 to 20 denier, and 500 to 4,000,000 (numbers/㎤) island-in-the-sea yarns may be preferably disposed within the optical modulated object. Furthermore, the refractive index of the sea portion may be preferably identical to that of the base material of the optical modulated object.

As shown in FIGS. 22 and 23, the island-in-the-sea yarn may be preferably weaved using

wefts

610a, 600b and

warps

600a, 610b. Any one of the weft and the end may be the island-in-the-sea yarn and the other of the weft and the warp may be the isotropic fiber. The weft or the warp may be preferably formed using 1 to 200 threads of the island-in-the-sea yarns.

As still another one of the preferred embodiment aspects of the optical modulation fiber, the birefringent fiber may be a conjugate yarn comprising an isotropic filling portion and anisotropic conjugate portions partitioned by the isotropic filling portion.

The isotropic filling portion may be preferably formed in plural numbers, and the plurality of isotropic filling portions may be preferably parallel to or intersected within the conjugate yarn. Consequently, the traverse section of the conjugate yarn may have a non-circular section such as oval fan-shaped of which non-circular degree is 0 to 100.

More specifically, FIG. 24 to 28 are cross-sectional views of the birefringent optical modulation fibers in accordance with an embodiment of the present invention. In FIG. 24, an isotropic filling portion 700a partitions a conjugate yarn in a longitudinal direction into two anisotropic conjugate portions 710a. In FIG. 25, an isotropic filling portion 700b partitions a conjugate yarn in a traverse direction into two anisotropic conjugate portions 710b. In FIG. 26, an isotropic filling portion 700c is formed in a '+' form. In FIG. 27, an isotropic filling portion 700d is formed in a 'Y' form. In FIG. 28, a plurality of isotropic filling portions 700e can be formed longitudinally. In this case, the plurality of isotropic filling portions 700e may be parallel to each other or not.

In a second embodiment of the present invention, the optical modulation spinned fiber of the birefringent polymers can be extended, arranged in one direction into a woven fabric or beam, and then impregnated in a base material and then fixing it thereto. The spinning and extending process of the optical modulation fiber or the weaving process of the woven fabric or beam can be performed using a known method, but not specially limited thereto. In impregnating the woven fabric or beam in the base material and fixing it thereto, a method of immersing non-woven fabric in monomer and/or oligomer solution, i.e., a precursor of the base material, and then polymerizing the precursor of a support medium using light and/or heat, a method of immersing woven fabric or beam in a polymer solution of a support medium and then removing a solvent, a method of making a support medium in fine powder, impregnating the fine powder in woven fabric or beam and then melting it, or the like may be used.

Furthermore, as another method, the present invention may be implemented using a melt extrusion method. More specifically, in the case in which a cross section vertical to a long axial direction of birefringent polymers, which are dispersed and arranged in a base material, has a polygonal shape, a profile extrusion method of partitioning an extruder discharge port into a plurality of spinnerets, extruding resin constituting the birefringent polymers in a polygonal form from every other spinneret, and extruding resin constituting the base material from a spinneret between the spinnerets may be adopted. In the case in which a cross section vertical to a long axial direction of birefringent polymers, which are dispersed and arranged in a support medium, is substantially circular, a profile extrusion method of partitioning an extruder discharge port into a plurality of spinnerets, extruding resin constituting the birefringent polymers in a round pole form from the spinnerets being consecutive within the cross section, and extruding resin constituting a base material from a spinneret between the spinnerets may be adopted. In these cases, the extruder and spinnerets can be designed such that different kinds of melted resins are alternately extruded from the spinnerets of the extruder in a specific form and thus form the above dispersed arrangement structure.

Accordingly, in the case in which an optical modulation fiber 810 comprising anisotropic core fibers disposed within an isotropic filler is used as a birefringent fiber as shown in FIG. 29, not only an optical modulation effect between a base material 800 and the birefringent fiber, but also an optical modulation effect between the isotropic filler and the anisotropic core fiber are generated within the birefringent fiber. Resultantly, the optical modulation effect of the optical modulated object can be improved significantly. In particular, in the case in which an island-in-the-sea yarn is used as the optical modulation fiber, a number of island portions can be disposed within the island-in-the-sea yarn. If pieces of the island-in-the-sea yarns are twisted to form a conjugate yarn, the conjugate yarns are threaded in the form of an end and weft and disposed in an optical modulated object, an excellent optical modulation effect, which cannot be compared with a case where a typical birefringent fiber is used, can be obtained.

The present invention will now be described in detail in connection with embodiments and experimental examples. The following embodiments and experimental examples illustrate only the present invention, and the scope of the present invention is not limited by the following embodiments and experimental examples.

After PEN resin of IV 0.53 was polymerized, raw yarn of undrawn yarn 150/24 was spinned. At this time, spinning was performed using a spinning temperature of 305℃ and a spinning speed of 1500 M/min. The obtained undrawn yarn was drawn three times at a temperature of 150℃, thus fabricating 50/24 drawn yarn. The drawn PEN fiber showed birefrigence, and the refractive indices of respective directions were nx=1.88, ny=1.57, and nz=1.57. After the fabricated PEN 50/24 drawn yarn 4,200 strands (since raw yarn of 24 strands behaves as one group, an actual number of fiber strands is 100,800 strands, i.e., 4,200*24) was wound on the beam of 762mm in width side by side, the wound beam was placed on a PC alloy sheet having a rear surface met-processed and then stacked by specific tension. Here, the refractive index of the PC alloy sheet was 1.57. Thereafter, a mixed UV-hardening coating resin of epoxy acrylate and urethane acrylate, which have the refractive index of 1.54, was applied to the PC alloy sheet in which the fibers were stacked and at a point where a mirror face roll was introduced and experienced primary and secondary UV-hardening, thus fabricating a blending sheet in which a birefringent fiber was stacked. The coating resin shows the refractive index of 1.54 before UV coating hardening, but shows the refractive index of 1.57 after hardening. Based on this fact, a sheet-shaped optical modulated object having a thickness of 40㎛ was fabricated.

A sheet-shaped optical modulated object was fabricated in the same manner as the embodiment 1 except that a sheath-core conjugate fiber was used instead of a typical drawn birefrigence PEN fiber. More specifically, in the used sheath-core conjugate fiber, the core portion of the sheath-core yarn was PEN (nx=1.88, ny=1.57, nz=1.57) and the sheath portion thereof was Co-PEN (nx=1.57, ny=1.57, nz=1.57) whose refractive index was not changed even by a drawing process. This composition experienced spinning in order to obtain undrawn yarn 150/24 and then drawn three times, thereby obtaining drawn yarn 50/24.

A sheet-shaped optical modulated object was fabricated in the same manner as the embodiment 1 except that an island-in-the-sea yarn was used instead of a typical drawn birefrigence PEN fiber. In the used island-in-the-sea yarn, anisotropic PEN (nx=1.88, ny=1.57, nz=1.57) was used as the island portions and 37 island portions were disposed within a filler of isotropic Co-PEN (nx=1.57, ny=1.57, nz=1.57). This composition experienced spinning in order to obtain undrawn yarn 150/24 and then drawn three times, thereby obtaining drawn yarn 50/24.

A sheet-shaped optical modulated object was fabricated in the same manner as the embodiment 3 except that the number of the island portions was 217.

A sheet-shaped optical modulated object was fabricated in the same manner as the embodiment 4 except that the island-in-the-sea yarn used in the embodiment experienced four conjugation (50/24×4) to obtain 200/96 yarn and then used.

In order to simplify a process of mixing the fiber used in the embodiment 4 in a sheet, 4,200 strands were weaved to have a weft density 50 numbers/inch using a beam, which was obtained by winding the strands in such a way as to be arranged 762mm in width side by side as in the embodiment 1. Plain weaving was applied in order to minimize the weft density. The fabricated woven fabric was stacked on the sheet while being released by a roll over a sheet extrusion die as in the embodiment 1, coated with a coating agent, and hardened, thereby fabricating a sheet-shaped optical modulated object.

A sheet-shaped optical modulated object was fabricated in the same manner as the embodiment 1 except that PEN (nx=1.88, ny=1.57, nz=1.57) and Co-PEN (nx=1.57, ny=1.57, nz=1.57) were used as the anisotropic conjugate portion instead of a typical drawn birefrigence PEN fiber, and a conjugate yarn using Co-PEN (nx=1.57, ny=1.57, nz=1.57) was used as the isotropic filling portion.

In order to improve optical use efficiency of an optical modulation object, a structured surface layer was formed over the optical modulation object of the embodiment 5. A sheet-shaped optical modulated object was fabricated in the same manner as the embodiment 5 except that the structured surface layer was formed using a prism pattern roll during a process of fabricating a blending sheet.

A sheet-shaped optical modulated object was fabricated in the same manner as the embodiment 1 except that a undrawn isotropic fiber of 150/24, comprised of Co-PEN(nx=ny=nz=1.57), was used instead of a birefringent fiber.

A sheet-shaped optical modulated object was fabricated in the same manner as the embodiment 3 except that a undrawn yarn having the island-in-the-sea structure comprised of PET (nx=ny=nz=1.57) and C0-PEN (nx=ny=nz=1.57) was used.

The following physical properties of the optical modulated objects, fabricated according to the embodiments 1 to 8 and the comparison examples 1 and 2 were evaluated and listed in Table 1.

1. Luminance

In order to measure the luminance of the fabricated optical modulated objects, the following tests were performed. After a panel was assembled on a 32" direct lighting type backlight unit equipped with a diffusion plate, two sheets of diffusion sheets, and the optical modulated object, luminance at 9 points was measured using BM-7 tester (TOPCON, Korea) and average values thereof were listed.

2. Transmittance

Transmittance was measured according to ASTM D1003 method using COH300A analysis equipment (NIPPON DENSHOKU Co., Japan).

3. Degree of polarization

The degree of polarization was measured using RETS-100 analysis equipment (OTSKA Co., Japan).

4. Moisture absorption factor

The optical modulated object was immersed in water of 23℃ for 24 hours according to ASTM D570 and a change in weight% before and after the process was measured.

5. Sheet sprout

The optical modulation object was assembled in a 32-inch backlight unit, left in a thermo-hygrostat under condition of 60℃ and 75% for 96 hours, and dissolved in order to monitor a degree in which sprouts of the optical modulation object were generated by the naked eyes. The results of the monitoring were marked by ○, △, ×.

○: Good, △: Normal, ×: Bad

6. UV-resistant property

The optical modulation object was irradiated by an output of a 130 mW-ultraviolet lamp (365 nm) at the height of 10 cm using SMDT51H (SEI MYUNG VACTRON CO., LTD., Korea) for 10 minutes. YI (Yellow Index) before and after the process was measured using SD-5000 analysis equipment (NIPPON DENSHOKU Co., Japan) and the yellowness index thereof was evaluated.

It could be seen from Table 1 that the embodiments 1 to 8, comprising the birefringent fiber, had better optical property than that of the comparison examples 1 and 2 comprising the isotropic fiber. Further, it could be seen that the optical property was increased significantly in the optical modulated object of the embodiment 3 or less using the island-in-the-sea yarn as compared to the embodiment 1 using a single birefringent fiber.

The optical modulated object of the present invention can be used for any usages if they require optical modulation and can be generally used in an optical sheet, a luminance-enhanced film, etc. of image output devices such as cameras, LCDs, and mobile phone liquid crystals.

Claims

An optical modulated object comprising a birefringent polymer disposed within a base material.
The optical modulated object of claim 1, wherein the base material is isotropic.
The optical modulated object of claim 2, wherein the base material comprises one or more selected from a group of polyethylene naphthalate (PEN), copolyethylene naphthalate (co-PEN), polyethylene terephthalate (PET), copolyethylene terephthalate (co-PET), polycarbonate (PC), polycarbonate (PC) alloy, polystyrene (PS), heat-resistant polystyrene (PS), polymethyl methacrylate (PMMA), polybutylene terephthalate (PBT), polypropylene (PP), polyethylene (PE), acrylonitrile butadiene styrene (ABS), polyurethane (PU), polyimide (PI), poly vinyl chloride (PVC), styrene acrylonitrile mixture (SAN), ethylene vinyl acetate (EVA), polyamide (PA), polyacetal (POM), phenol, epoxy (EP), urea (UF), melanin (MF), non-saturated polyester (UP), silicon (SI), elastomers and cycloolefin polymer.
The optical modulated object of claim 1, wherein the birefringent polymer comprises one or more selected from a group of polyethylene naphthalate (PEN), copolyethylene naphthalate (co-PEN), polyethylene terephthalate (PET), copolyethylene terephthalate (co-PET), polycarbonate (PC), polycarbonate (PC) alloy, polystyrene (PS), heat-resistant polystyrene (PS), polymethyl methacrylate (PMMA), polybutylene terephthalate (PBT), polypropylene (PP), polyethylene (PE), acrylonitrile butadiene styrene (ABS), polyurethane (PU), polyimide (PI), poly vinyl chloride (PVC), styrene acrylonitrile mixture (SAN), ethylene vinyl acetate (EVA), polyamide (PA), polyacetal (POM), phenol, epoxy (EP), urea (UF), melanin (MF), non-saturated polyester (UP), silicon (SI), elastomers and cyclo olefin polymer.
The optical modulated object of claim 1, wherein the birefringent polymer is disposed in plural numbers within the base material in one direction.
The optical modulated object of claim 5, wherein the birefringent polymers are disposed within the base material vertically to a light source.
The optical modulated object of claim 1, wherein the birefringent polymer is comprised in a volume of 1 to 90% based on the total optical modulated object.
The optical modulated object of claim 1, wherein the birefringent polymer is disposed 500 to 1010 in number with respect to the optical modulated object 1㎤.
The optical modulated object of claim 1, wherein the optical modulated object comprises a structured surface layer.
The optical modulated object of claim 9, wherein the structured surface layer is formed on a surface from which light is output.
The optical modulated object of claim 9, wherein the structured surface layer has a prism shape.
The optical modulated object of claim 11, wherein the structured surface layer is an irregular prism shape.
The optical modulated object of claim 9, wherein the structured surface layer has a lenticular shape.
The optical modulated object of claim 13, wherein the structured surface layer has an irregular lenticular shape.
The optical modulated object of claim 9, wherein the structured surface layer has a convex lens or micro lens shape.
The optical modulated object of claim 15, wherein the structured surface layer has an irregular convex lens or micro lens shape.
The optical modulated object of claim 9, wherein the birefringent polymer is disposed or not disposed in the structured surface layer.
The optical modulated object of claim 1, wherein at least one surface of the optical modulated object is experienced by Matt treatment.
The optical modulated object of claim 1, wherein light irradiated from a light source transmit through the optical modulated object, and the transmitted light is natural light or polarized light.
The optical modulated object of claim 1, wherein the birefringent polymer is disposed within the base material in a stack form.
The optical modulated object of claim 1, wherein the birefringent polymer is randomly disposed within the optical modulated object.
The optical modulated object of claim 1, wherein the birefringent polymer is a birefringent fiber.
The optical modulated object of claim 22, wherein the birefringent fiber is an optical modulation fiber comprising an anisotropic core fiber.
The optical modulated object of claim 23, wherein the optical modulation fiber comprises an anisotropic core fiber disposed within a filler.
The optical modulated object of claim 24, wherein the filler is isotropic.
The optical modulated object of claim 25, wherein the filler comprises one or more selected from a group of polyethylene naphthalate (PEN), copolyethylene naphthalate (co-PEN), polyethylene terephthalate (PET), copolyethylene terephthalate (co-PET), polycarbonate (PC), polycarbonate (PC) alloy, polystyrene (PS), heat-resistant polystyrene (PS), polymethyl methacrylate (PMMA), polybutylene terephthalate (PBT), polypropylene (PP), polyethylene (PE), acrylonitrile butadiene styrene (ABS), polyurethane (PU), polyimide (PI), poly vinyl chloride (PVC), styrene acrylonitrile mixture (SAN), ethylene vinyl acetate (EVA), polyamide (PA), polyacetal (POM), phenol, epoxy (EP), urea (UF), melanin (MF), non-saturated polyester (UP), silicon (SI), elastomers and cyclo olefin polymer.
The optical modulated object of claim 24, wherein the anisotropic core fiber comprises one or more selected from a group of polyethylene naphthalate (PEN), copolyethylene naphthalate (co-PEN), polyethylene terephthalate (PET), copolyethylene terephthalate (co-PET), polycarbonate (PC), polycarbonate (PC) alloy, polystyrene (PS), heat-resistant polystyrene (PS), polymethyl methacrylate (PMMA), polybutylene terephthalate (PBT), polypropylene (PP), polyethylene (PE), acrylonitrile butadiene styrene (ABS), polyurethane (PU), polyimide (PI), poly vinyl chloride (PVC), styrene acrylonitrile mixture (SAN), ethylene vinyl acetate (EVA), polyamide (PA), polyacetal (POM), phenol, epoxy (EP), urea (UF), melanin (MF), non-saturated polyester (UP), silicon (SI), elastomers and cyclo olefin polymer, and has anisotropy.
The optical modulated object of claim 24, wherein:

a difference in a refractive index of the filler and the anisotropic core fiber with respect to two axial directions is 0.01 or less, and

a difference in a refractive index of the filler and the anisotropic core fiber with respect to the remaining one axial direction is 0.03 or more.
The optical modulated object of claim 24, wherein the anisotropic core fiber comprises a fiber outer cover surrounding a fiber core.
The optical modulated object of claim 24, wherein the optical modulated object comprises a plurality of optical modulation fibers having different cross sections.
The optical modulated object of claim 24, wherein one or more of the filler and the anisotropic core fiber comprise birefringent polymer substance.
The optical modulated object of claim 24, wherein one or more of the polymer optical modulation fiber and the anisotropic core fiber are longitudinally drawn.
The optical modulated object of claim 24, wherein the optical modulation fiber is a sheath-core conjugate fiber.
The optical modulated object of claim 33, wherein the sheath-core conjugate fiber has a core portion correspond to the anisotropic core fiber and a sheath portion correspond to the filler.
The optical modulated object of claim 24, wherein:

the optical modulation fiber is an island-in-the-sea yarn,

the anisotropic core fiber corresponds to an island portion of the island-in-the-sea yarn, and

the filler corresponds to a sea portion of the island-in-the-sea yarn.
The optical modulated object of claim 35, wherein the sea portion and the island portion have different refractive indices in at least one direction.
The optical modulated object of claim 35, wherein:

a difference in a refractive index of the sea portion and the island portion with respect to two axial directions is 0.03 or less, and

a difference in a refractive index of the sea portion and the island portion with respect to the remaining one axial direction is 0.05 or more.
The optical modulated object of claim 35, wherein an area ratio of the sea portion and the island portion is in the range of 2 : 8 to 8 : 2.
The optical modulated object of claim 35, wherein the island portion is disposed in plural numbers within the island-in-the-sea yarn.
The optical modulated object of claim 35, wherein:

the sea portion is isotropic, and

the island portion is anisotropic.
The optical modulated object of claim 35, wherein the sea portion comprises one or more selected from a group of polyethylene naphthalate (PEN), copolyethylene naphthalate (co-PEN), polyethylene terephthalate (PET), copolyethylene terephthalate (co-PET), polycarbonate (PC), polycarbonate (PC) alloy, polystyrene (PS), heat-resistant polystyrene (PS), polymethyl methacrylate (PMMA), polybutylene terephthalate (PBT), polypropylene (PP), polyethylene (PE), acrylonitrile butadiene styrene (ABS), polyurethane (PU), polyimide (PI), poly vinyl chloride (PVC), styrene acrylonitrile mixture (SAN), ethylene vinyl acetate (EVA), polyamide (PA), polyacetal (POM), phenol, epoxy (EP), urea (UF), melanin (MF), non-saturated polyester (UP), silicon (SI), elastomers and cyclo olefin polymer.
The optical modulated object of claim 35, wherein the island portion comprises one or more selected from a group of polyethylene naphthalate (PEN), copolyethylene naphthalate (co-PEN), polyethylene terephthalate (PET), copolyethylene terephthalate (co-PET), polycarbonate (PC), polycarbonate (PC) alloy, polystyrene (PS), heat-resistant polystyrene (PS), polymethyl methacrylate (PMMA), polybutylene terephthalate (PBT), polypropylene (PP), polyethylene (PE), acrylonitrile butadiene styrene (ABS), polyurethane (PU), polyimide (PI), poly vinyl chloride (PVC), styrene acrylonitrile mixture (SAN), ethylene vinyl acetate (EVA), polyamide (PA), polyacetal (POM), phenol, epoxy (EP), urea (UF), melanin (MF), non-saturated polyester (UP), silicon (SI), elastomers and cyclo olefin polymer and is anisotropic.
The optical modulated object of claim 35, wherein the island-in-the-sea yarn has a thickness of 0.3 to 20 denier.
The optical modulated object of claim 35, wherein 500 to 4,000,000 number/㎤ of the island-in-the-sea yarns are disposed within the optical modulated object.
The optical modulated object of claim 35, wherein a cross section of the island-in-the-sea yarn is circular or oval.
The optical modulated object of claim 35, wherein a cross section of the island-in-the-sea yarn has a non-circular section.
The optical modulated object of claim 35, wherein a cross section of the island portion has a non-circular section.
The optical modulated object of claim 35, wherein a refractive index of the sea portion is identical to that of the base material according to claim 1.
The optical modulated object of claim 35, wherein the island-in-the-sea yarn is weaved in wefts and warps.
The optical modulated object of claim 49, wherein:

any one of the weft and the warp is the island-in-the-sea yarn, and

the other of the weft and the warp is an isotropic fiber.
The optical modulated object of claim 49, wherein the weft or the warp is formed by 1 to 200 strands of gathered island-in-the-sea yarns.
The optical modulated object of claim 22, wherein the birefringent fiber is a conjugate yarn comprised of isotropic filling portions and anisotropic conjugate portions partitioned by the isotropic filling portion.
The optical modulated object of claim 52, wherein a cross section of the conjugate yarn is a non-circular section.
The optical modulated object of claim 52, wherein the anisotropic conjugate portion is formed in plural numbers.
The optical modulated object of claim 52, wherein a plurality of the isotropic filling portions are parallel to each other or cross each other within the conjugate yarn.
An optical modulated object comprising:

a birefringent optical modulation fiber disposed within a base material;

wherein the birefringent optical modulation fiber comprises an anisotropic core fiber disposed within a filler, a refractive index of the anisotropic core fiber is different from that of the filler in at least one axial direction, and a plurality of birefringent interface is formed between the anisotropic core fiber and the filler.
The optical modulated object of claim 56, wherein the base material is isotropic.
The optical modulated object of claim 56, wherein the filler is isotropic.
The optical modulated object of claim 56, wherein:

a difference in a refractive index of the anisotropic core fiber and the filler in two axial directions is 0.03 or less, and

a difference in a refractive index of the anisotropic core fiber and the filler in the remaining one axial direction is 0.05 or more.
The optical modulated object of claim 56, assuming that a refractive index of a base material in a x-axis direction is nX1, a refractive index of the base material in a y-axis direction is nY1 and a refractive index of the base material in a z-axis direction of is nZ1, and a refractive index of a birefringent optical modulation fiber in the x-axis direction is nX2, a refractive index of the birefringent optical modulation fiber in the y-axis direction is nY2 and a refractive index of the birefringent optical modulation fiber in the z-axis direction is nZ2, at least one of the refractive indices of the base material in the X, Y and Z-axis directions is identical to at least one of the refractive indices of the birefringent optical modulation fiber in the X, Y and Z-axis directions.
The optical modulated object of claim 60, wherein the nX2 > nY2 = nZ2.
The optical modulated object of claim 60, wherein the birefringent optical modulation fiber comprises an anisotropic core fiber disposed within a filler.
The optical modulated object of claim 56, wherein, assuming that a refractive index of the anisotropic core fiber in a x-axis direction is nX2, a refractive index of the anisotropic core fiber in a y-axis direction is nY2 and a refractive index of the anisotropic core fiber in a z-axis direction is nZ2, and a refractive index of the filler in the x-axis direction is nX3, a refractive index of the filler in a y-axis direction is nY3 and a refractive index of the filler in a z-axis direction is nZ3, an absolute value of a difference in the refractive index between the nX2 and nX3 is 0.05 or more.
The optical modulated object of claim 63, wherein the absolute value in a difference in the refractive index between the nY2 and nY3 or nZ2 and nZ3 is less than 0.03.
An optical molulating system comprising

a light source; and

an optical modulated object which are located over the light source and wherein the birefringent optical modulation fiber composed of an anisotropic core fiber disposed within a base material molulates incidence light from the light source and thus emits the modulated light.