TW201712378A - Optical sheet and optical display comprising the same - Google Patents

Abstract

An optical sheet and an optical display including the same are disclosed. The optical sheet includes: a protective part including a light incident plane and a light exit plane facing the light incident plane; an optical pattern layer formed on the light incident plane; and a polarizer formed on the light exit plane, wherein light is incident on the light incident plane at an angle ([theta]1) of about 50 DEG to about 85 DEG with respect to a normal line of the light incident plane, and brightness of side-lobe exiting the light exit plane at an angle ([theta]2) of about ± 30 DEG or more with respect to the normal line of the light exit plane at light exit angle is about 10% or less of the brightness of light exiting the light exit plane in a normal direction thereof.

Description

Optical sheet and optical display containing the same

The present invention relates to an optical sheet and an optical display comprising the same.

A typical liquid crystal display (LCD) contains colored elements that emit red, green, and blue to achieve a desired color via its combination. In order to improve the color gamut of an LCD while ensuring its flexibility and photostability, quantum dot LCDs produced by applying quantum dots to color elements of an LCD have attracted attention in the related art.

Therefore, when a typical backlight unit (BLU) of an LCD having a low degree of collimation is used in an optical display to which quantum dots are applied, light passing through a thin film transistor (TFT) enters a quantum adjacent thereto. The dots, in turn, cause the color reproduction of the optical display to deteriorate. Therefore, optical displays employing quantum dots need to emit highly collimated light in order to improve the color gamut of the optical display. Optical sheets capable of realizing this technology are under development in the related art.

The background of the present invention is disclosed in Korean Patent Publication No. 2000-0068644 A.

According to an aspect of the invention, an optical sheet may include: a protective member including a light incident plane and a light exiting plane toward the light incident plane; an optical pattern layer formed on the light incident plane; and the light Emitting a polarizer formed on a plane, wherein light is incident on the light incident plane at an angle (θ1) of about 50° to about 85° with respect to a normal to the plane of incidence of the light, and at a light exit angle Relative to the normal of the light exiting plane, an angle of about ±30° or more than ±30° (θ2) is emitted from the side of the light exiting plane, and the brightness is emitted in the normal direction of the light exiting plane. The light emits about 10% or less of the brightness of the plane light.

The optical pattern layer can comprise a plurality of unit prisms disposed thereon in succession, and each of the unit prisms can have a height (H) of from about 2 microns to about 65 microns, a distance of from about 5 microns to about 60 microns. (P) and an apex angle (α) of from about 50° to about 100°.

The optical pattern layer may include an optical pattern and the arrangement direction of the optical pattern may be parallel to the absorption axis of the polarizer.

The optical pattern layer may be integrally formed with the protective member via the adhesive/bonding layer.

The optical sheet may further comprise a base layer between the protective member and the optical pattern layer.

The protective member may be integrally formed with the base layer via the adhesive/bonding layer.

Each of the unit prisms may have an apex angle (α) of from about 63° to about 67°.

According to another aspect of the present invention, an optical display may include: a collimating member; a liquid crystal layer formed on the collimating member and including a thin film transistor; a polarizer formed on the liquid crystal layer; and A light-emitting layer formed on a polarizer, wherein the collimating member comprises an optical sheet according to the present invention.

The optical display can further include a light guide plate disposed below the optical sheet.

In the following, the embodiments of the present invention will be described in detail with reference to the accompanying drawings, in which the present invention can be easily implemented by those skilled in the art. It is to be understood that the invention is not limited to the following examples and may be practiced in various ways. It should be noted that the drawings are not to scale in scale and are exaggerated in some dimensions, such as width, length, thickness, and the like, for clarity of the description in the drawings. Throughout the drawings, similar components will be represented by similar graphical component symbols.

As used herein, reference is made to the spatially relative terms such as "upper" and "lower" as used in the drawings. Therefore, it should be understood that the "upper surface" can be used interchangeably with the "lower surface". It will be understood that when a layer is referred to as being "on" another layer, the layer may be formed directly on the other layer or the intervening layer may be present. On the other hand, when a layer is referred to as "directly on" another layer, there is no intervening layer.

As used herein, the term "collimation" means the operation of making light parallel to a certain direction.

Herein, "+" means a clockwise direction with respect to the normal of the reference plane and "-" means a counterclockwise direction with respect to the normal of the reference plane. The reference plane can be a light exit plane or a light incident plane.

As used herein, the term "side lobes" means that the light component of the light exiting plane is emitted at an angle (θ2) of about ±30° or greater than ±30° with respect to the normal to the reference plane. In particular, the term "side lobes" means that the light exits the plane at an angle of +30° to +90° (θ2) or at an angle of -90° to -30° (θ2) with respect to the normal to the reference plane. The light component.

As used herein, "±X° to ±Y°" means the value of +X° to +Y° and/or the value of -Y° to -X° (X and Y are both positive numbers).

As used herein, "high-collimation" means that the side lobes have low brightness and also means that the angle between light and a direction is a certain value or less than a certain value or is emitted at an angle or less. Light provides higher brightness.

As used herein, "formed integrally with" means that two layers (components) are formed to avoid voids (or air layers) therebetween, or an intervening layer may be formed between the two layers to avoid voids (or air therebetween) therebetween. Floor). For example, the intervening layer can be an adhesive/bonded layer or a base layer.

Hereinafter, an optical sheet according to an embodiment of the present invention will be described with reference to FIGS. 1 and 2. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a schematic cross-sectional view of an optical sheet in accordance with one embodiment of the present invention. Fig. 2 is a schematic view showing the relationship between the normal line, the incident angle, and the exit angle.

Referring to FIG. 1, an optical sheet 100 according to an embodiment of the present invention includes a protective member 10 including a light incident plane 13 and a light exiting plane 15 facing the light incident plane 13; formed on the light incident plane 13 An optical pattern layer 20; and a polarizer 30 formed on the light exiting plane 15.

The protective member 10 is formed on one surface of the polarizer 30 and protects the polarizer 30. The protective member 10 protects the polarizer 30 from thermal shock and/or moisture penetration, thereby preventing the polarizer 30 from being broken. The optical pattern layer 20 is formed on the light incident plane 13 of the protective member 10. The protective member 10 can be realized by a protective film or a protective layer.

The protective film may comprise an optically transparent resin commonly used in the art. For example, the protective film may be formed of at least one of: cyclic polyolefin resins, including an amorphous olefin polymer (COP) and the like; acyclic polyolefin Non-cyclic polyolefin resins; poly(meth)acrylate resins; polycarbonate resins; polyester resins, including polyethylene terephthalate Polyethylene terephthalate (PET) and the like; cellulose ester resins, including triacetyl cellulose and the like; polyethersulfone resins; polysulfone resins Polyamide resins; polyimide resins; polyvinyl alcohol resins; polyvinyl chloride resins; and polyvinylidene resins Chloride resins). The protective film can have a thickness of from about 10 microns to about 200 microns, such as from about 30 microns to about 120 microns. Within this range, a protective film can be used in an optical display.

The protective layer may have a thickness within a predetermined range in order to enhance the mechanical strength of the polarizer while achieving a compact structure of the optical sheet. The protective layer can have a thickness from about 1 micron to about 200 microns, such as from about 10 microns to about 120 microns, such as from about 1 micron to about 30 microns, such as from about 2 microns to about 25 microns. Within this thickness range, the protective layer can be used in the polarizing plate and can enhance the mechanical strength of the polarizing plate.

Although the protective member 10 is shown as being formed only on one surface of the polarizer 30 in FIG. 1, the protective member 10 may be formed on both surfaces of the polarizer 30. Further, although not shown in FIG. 1, a bonding layer may be formed between the polarizer 30 and the protective member 10. The bonding layer can be formed from typical compositions known to those of ordinary skill in the art. In addition, although not shown in FIG. 1, a typical protective film may be further formed on the upper surface of the polarizer 30.

The optical pattern layer 20 is formed on the light incident plane 13 of the protective member 10. The optical pattern layer 20 serves as a light collecting layer that collects light received from a light guiding plate or another optical sheet (not shown in FIG. 1) such that light entering the optical pattern layer 20 can sequentially emit the protective member 10 and the polarizer 30, Further, the brightness and luminous efficiency are improved. The optical pattern layer 20 can serve as a collimating component of the optical display. In the structure in which the optical pattern layer 20 is formed on the light incident plane 13, the optical sheet provides side lobes of low brightness and high collimation, thereby improving the color gamut of the optical display including the quantum dots.

In the optical sheet 100 according to this embodiment, the optical pattern layer 20 is integrally formed with the protective member 10. In a structure in which the optical pattern layer 20 and the protective member 10 are integrally formed in order to prevent an air layer from being formed between the optical pattern layer 20 and the protective member 10, the side lobe brightness can be further reduced by the light of the protective member 10 or the optical sheet 100 and It has high collimation and thus improves the color gamut of optical displays containing quantum dots.

The optical pattern layer 20 includes a reverse prism as a light collecting member to improve color gamut and brightness. In particular, as described below, the appropriately designed reverse prism of the optical pattern layer further improves the color gamut and brightness of the quantum dot liquid crystal display.

The lower surface of the protective member 10 may constitute a light incident plane 13 and the upper surface of the protective member 10 may constitute a light exit plane 15.

Optical pattern layer 20 can have a thickness of about 1.35 or greater than 1.35, or about 1.40 or greater than 1.40, specifically from about 1.35 to about 1.55, more specifically from about 1.40 to 1.60, from about 1.40 to about 1.55, or from about 1.45 to about 1.60. Refractive index. Within this range of refractive indices, the optical pattern layer provides a good light collection effect and reduces the brightness of the light exiting the plane at an angle of from about ±30° to about ±90° with respect to the normal to the light exit plane.

The optical pattern layer 20 may be formed of an optically clear UV curable resin. In particular, the UV curable resin may comprise (meth)acrylic, polycarbonate, poly(methyl(meth)acrylate), and At least one of urethane resins.

The optical pattern layer 20 includes one or more optical patterns arranged in a predetermined direction. The optical pattern of the optical pattern layer will be described in more detail with reference to FIG.

Polarizer 30 polarizes natural or artificial light such that the screen of the optical display is visible and can generally be formed from a polyvinyl alcohol film. In one embodiment, the polarizer is produced by modifying a polyvinyl alcohol film (such as a partially formalized polyvinyl alcohol film) with iodine or a dichroic dye. Alternatively, it is dyed with an acetoacetyl group-modified polyvinyl alcohol film, and then the film is stretched in a machine direction (MD). In particular, the polarizer 30 can be produced via swelling, dyeing, and stretching. In general, the direction of stretching becomes the absorption axis of the polarizer and the vertical direction becomes its transmission axis. Methods for performing various processes are generally known to those of ordinary skill in the art. In another embodiment, the polarizer can be produced by preparing an acid catalyst impregnated membrane using an acid catalyst and polyvinyl alcohol, dry stretching and dehydrating the acid catalyst impregnated membrane, hydrating the dehydrated membrane, and wetting Stretch and neutralize the hydrated film.

On the optical pattern layer 20, the arrangement direction of the optical patterns may be parallel to the absorption axis of the polarizer 30. Herein, "parallel" means not only a structure in which the angle between the arrangement direction of the optical pattern and the absorption axis of the polarizer is 0, but also a structure in which an angle is defined therebetween. For example, on the optical pattern layer 20, the optical pattern can be configured such that the angle defined between the configuration direction of the optical pattern and the absorption axis of the polarizer 30 is in the range of about -5[deg.] to about +5[deg.]. In this paper, assume that the absorption axis of the polarizer is 0°, "+" is defined as the clockwise direction of the polarizer and "-" is defined as its counterclockwise direction. In particular, when the optical pattern of the optical pattern layer is disposed in the direction of the absorption axis of the polarizer in the fabrication of the optical sheet, the optical display can maximize the luminous efficiency of light emitted from the light source and then through the light guide plate because In Brewster's law, the polarization component is separated from the light passing through the light guide plate, thereby increasing the transmission efficiency of the electric field component reflected by the optical pattern layer. The higher angle between the absorption axis of the polarizer and the arrangement direction of the optical pattern of the optical pattern layer provides a lower transmission efficiency of the electric field, and the right angle between the absorption angle and the arrangement direction of the optical pattern provides the lowest transmission efficiency, thereby reducing the brightness .

Polarizer 30 can have a thickness of from about 3 microns to about 50 microns. Within this range, polarizers can be used in optical displays.

Referring to Fig. 2, in the protective member 10, each of the normals of the light incident plane 13 and the light exiting plane 15 is a line perpendicular to the surface of the protective member 10, and the light incident on the light incident plane 13 is relative to The angle of the normal to the light incident plane 13 is θ ₁ and the angle of the light exiting the light exit plane 15 with respect to the normal to the light exit plane 15 is θ ₂ .

The light incident on the optical sheet 100 may have an angle of from about 50 to about 85, in particular from about 60 to about 80, with respect to the normal to the light incident plane 13 by the light guiding plate. Within this range of incident angles, the optical sheet provides light collection and high collimation through the light of the optical sheet.

With the optical sheet 100 according to this embodiment, the brightness of the side lobes of the light exiting plane 15 is emitted at an angle of about ±30° or more than ±30° with respect to the normal to the light exit plane 15 at the light exit angle to be emitted at the light. The luminance of the light exiting the plane 15 in the normal direction of the plane 15 is about 10% or less than 10%. In some embodiments, for the optical sheet 100 according to this embodiment, the side lobes of the light exiting plane 15 are emitted at an angle of about ±30° or greater than ±30° with respect to the normal to the light exit plane 15 at the light exit angle. The brightness may be about 5% or less than 5% of the brightness of the light exiting the light exiting plane 15 in the normal direction of the light exit plane 15. Within this range, the optical sheet has good effects on light collection for the target quantum dot element, and can reduce side lobe brightness while providing high collimation, thereby improving the color gamut of the optical display.

Next, an optical sheet according to another embodiment of the present invention will be described with reference to FIG.

Figure 3 is a cross-sectional view of an optical sheet in accordance with another embodiment of the present invention. Referring to FIG. 3, an optical sheet 200 according to another embodiment may include a reverse prismatic optical pattern layer 23. The optical sheet 200 shown in FIG. 3 is substantially identical to the optical sheet of FIG. 1 except that the optical pattern layer 20 is described in more detail.

The reverse prism optical pattern layer 23 is a light collecting layer having a prism pattern thereon, and means an optical pattern layer formed to allow light incident thereon to pass through the peak of each of the prisms and then pass through the bottom thereof. The optical sheet 200 having the reverse prism optical pattern layer 23 formed thereon can improve the brightness of the liquid crystal display.

The reverse prism optical pattern layer 23 includes a plurality of unit prisms continuously disposed on the protective member 10. Additionally, in this embodiment, the light entering the optical sheet 200 may have an angle of incidence in the range of from about 50° to about 85°, specifically from about 60° to about 80°, relative to the normal to the light incident plane 13. .

The unit prisms may have the same or different heights (H). For example, the unit prisms can have a height of from about 2 microns to about 65 microns, specifically from about 5 microns to about 40 microns, and more specifically from about 10 microns to about 30 microns. Within this range, the optical sheet is not subjected to a moiré phenomenon and has a good light collecting effect. The unit prisms can have the same or different spacing (P). In particular, the unit prisms can have a pitch (P) of from about 5 microns to about 60 microns, such as from about 10 microns to about 30 microns, such as from about 10 microns to about 25 microns, such as from about 10 microns to about 20 microns. Furthermore, the unit prisms can be configured to have a separation distance between the pitches (P). The separation distance can range from about 0 microns to about 3 microns and provides good processability in the manufacture of optical sheets in accordance with the present invention. Within this range, the optical sheet is not subjected to the phenomenon of ripple and has a good light collecting effect. The unit prisms can have from about 50° to about 100°, such as from about 50° to about 80°, specifically from about 60° to about 70°, more specifically from about 63° to about 67°, from about 64° to about 67°. °, or an apex angle (α) of about 65° to about 67°. Within this range, the optical sheet collects light at an angle of about 25° or less relative to the normal to the light exit plane, thereby improving the color gamut and brightness of the quantum dot element while minimizing the generation of the rainbow point. . In this embodiment, the optical sheet may be formed such that the brightness of the light exiting the light exiting the plane at an angle of about ±30° or greater than ±30° at the exit angle relative to the normal of the light exiting plane becomes incident at the light. The brightness of the light exiting the plane in the normal direction of the plane is about 10% or less than 10%.

The reverse prism optical pattern layer 23 can have a refractive index in the range of from about 1.35 to about 1.70, specifically from about 1.40 to about 1.70, from about 1.40 to about 1.55, or from about 1.45 to about 1.60. Within this refractive index range, the reverse prismatic optical pattern layer provides good light collection for the light emitted by the vector sub-dot element and can be reduced by about ±30° or greater relative to the normal to the light exit plane. The brightness of the side lobes of the light exiting the plane is emitted by an angle of ±30°, preferably about ±30° to about ±90°, more preferably about ±30° to about ±40°.

The reverse prism optical pattern layer 23 may be formed on one surface of the protective member 10 via UV curing. For example, in forming the optical sheet 200, in a case where one surface of the protective member 10 is brought into contact with a mold engraving roll having a prism pattern formed thereon, the transparent resin composition is injected to the engraving roll and the protective member 10 The gap between the spaces is followed by curing of the transparent resin composition by UV irradiation. Subsequently, the coating of the cured transparent resin composition is separated from the engraving roll, thereby forming a reverse prism optical pattern layer on the protective member 10. The transparent resin composition is transparent in the visible light range and may include a UV curable transparent resin. In particular, the transparent resin may include, but is not limited to, at least one of the following: acrylic resins, polyacetal resins, polycarbonate resins, styrene resins (styrene) Resins), polyester resins, vinyl resins, polyphenylene ether resins, polyolefin resins, cycloolefin resins, acrylonitrile-butadiene Acrylonitrile-butadiene-styrene copolymer resins, polyacrylate resins, polyarylsulfone resins, polyethersulfone resins, polyphenylene sulfide resins (polyphenyl sulfide resins) Polyphenylene sulfide resins), polyethylene naphthalate resins, polyethylene resins or fluorine resins. The transparent resin composition may further comprise a typical photopolymerization initiator to achieve UV curing.

Next, an optical sheet according to another embodiment of the present invention will be described with reference to FIG. 4 is a cross-sectional view of an optical sheet in accordance with another embodiment of the present invention.

Referring to FIG. 4, in an optical sheet 300 according to another embodiment, the optical pattern layer 20 may be integrally formed with the protective member 10 via an adhesive/bonding layer 40. In the optical sheet 300, the air layer between the optical pattern layer 20 and the protective member 10 is removed, whereby the light passing through the optical sheet has a high degree of collimation, thereby improving the color of the optical display including the optical sheet according to this embodiment. area. The optical sheet 300 according to this embodiment is substantially identical to the optical sheet 100 of FIG. 1 except that the optical sheet 300 further includes an adhesive/bonding layer 40 between the optical pattern layer 20 and the protective member 10.

Adhesive/bonding layer 40 can comprise an adhesive layer, a bonding layer, or a combination thereof.

In one embodiment, the adhesion/bonding layer 40 may be formed of a composition comprising a (meth)acrylic resin and a curing agent.

(meth)acrylic resin has an alkyl group, a hydroxyl group, an aromatic group, a carboxylic acid group, an alicyclic group ( An alicyclic group) or a (meth)acrylic copolymer of a hetero-alicyclic group and may comprise a typical (meth)acrylic resin. In particular, a (meth)acrylic resin may be formed from a monomer mixture comprising at least one of: an unsubstituted C ₁ to C ₁₀ alkyl group ( a (meth)acrylic monomer, a (meth)acrylic monomer comprising a C ₁ to C ₁₀ alkyl group having at least one hydroxyl group a (meth)acrylic monomer comprising a C ₆ to C ₂₀ aromatic group, a (meth)acrylic monomer including a carboxylic acid group ((meth Acrylic monomer), a (meth)acrylic monomer including a C ₃ to C ₂₀ alicyclic group, and including nitrogen (N), oxygen (O), and sulfur (S) At least one of the C ₃ to C ₁₀ hetero-alicyclic group of (meth)acrylic monomers.

The curing agent may include at least one of a polyfunctional (meth) acrylate, an isocyanate curing agent, and a carbodiimide curing agent. Polyfunctional (meth)acrylate may include, but is not limited to, a bifunctional (meth)acrylate such as hexanediol diacrylate; Trifunctional (meth)acrylate, such as trimethylolpropane tri(meth)acrylate; tetrafunctional (meth) acrylate tetrafunctional (meth) Acrylate), such as pentaerythritol tetra(meth)acrylate; pentafunctional (meth)acrylate, such as dipentaerythritol penta (meth) acrylate (dipentaerythritol penta) (meth)acrylate); and hexafunctional (meth)acrylate, such as dipentaerythritol hexa (meth)acrylate. The isocyanate curing agent may comprise a typical isocyanate group-containing curing agent known to those of ordinary skill in the art. The carbodiimide curing agent includes one or more carbodiimide groups and may comprise a typical carbodiimide curing agent known to those of ordinary skill in the art. .

The composition for the adhesion/bonding layer may further comprise a silane coupling agent.

The silane coupling agent may comprise at least one of epoxysilane, mercaptosilane, aminosilane, vinyltrichlorosilane, vinyl trimethoate. 3-trilycidoxypropyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 2-aminoethylethyl 3-methoxyloxypropyltrimethoxysilane 2-aminoethyl-3-aminopropylmethyldimethoxysilane and 3-ureidopropyltriethoxysilane.

The composition for the adhesive/bonding layer may comprise 100 parts by weight of (meth)acrylic resin, from about 0.1 parts by weight to about 30 parts by weight of curing agent, and from about 0.1 parts by weight to about 20 parts by weight. A silane coupling agent. Within this range, the adhesive/bonding layer can sufficiently bond the optical pattern layer 20 to the protective member 10.

The composition for the adhesive/bonding layer may further comprise a light diffusing agent to achieve further diffusion of light.

The composition for the adhesive/bonding layer may further comprise an initiator. The starter can be, but is not limited to, a hot starter or a photoinitiator. The photoinitiator can comprise a photo-radical initiator as a typical photoinitiator.

In another embodiment, the adhesion/bonding layer 40 may comprise a composition for an adhesion/bonding layer comprising, but not limited to, a (meth) acrylate resin and an epoxy resin ( At least one of epoxy resin).

The composition comprising a (meth)acrylate resin for the adhesion/bonding layer may comprise a (meth)acrylate-modified urethane , epoxy (meth)acrylate, isocyanurate (meth)acrylate, and (meth)acrylate group At least one of the compounds. The composition comprising a (meth) acrylate resin for the adhesion/bonding layer may further comprise a polymerization initiator or a silane coupling agent. Any initiator capable of generating radicals by heating or light can be used as the polymerization initiator. For example, the polymerization initiator may include, but is not limited to, lauroyl peroxide, t-butyl peroxylaurate, hexanoic acid 1,1,3,3- Trimethyl butylperoxy-2-ethyl hexanoate, 2,5-dimethyl-2,5-di(2-ethyl 2,5-dimethyl-2,5-di(2-ethylhexanoyl peroxy) hexane, 1-cyclohexyl-1-methylethylperoxy-2-ethyl hexanoate 1-cyclohexyl-1-methylethyl peroxy-2-ethyl hexanoate, 2,5-dimethyl-2,5-di(m-tolylmethyl peroxy)hexane (2,5-dimethyl-2) ,5-di(m-toluoyl peroxy) hexane), t-butyl peroxy isopropyl monocarbonate, t-butylperoxy-2-ethylhexyl monocarbonate T-butyl peroxy-2-ethylhexyl monocarbonate, t-hexyl peroxybenzoate, t-butyl peroxy acetate, Dicumyl peroxide, 2,5,-dimethyl-2,5-di(t-butylperoxy) Alkyl (2,5,-dimethyl-2,5-di(t-butyl peroxy) hexane), t-butyl cumyl peroxide, third hexylperoxy neodecanoate (t-hexyl peroxy neodecanoate), t-hexyl peroxy-2-ethyl hexanoate, tert-butylperoxy-2-2-ethylhexanoate T-butyl peroxy-2-2-ethylhexanoate, t-butyl peroxy isobutyrate, 1,1-bis(t-butylperoxy)cyclohexane (1,1-bis(t-butyl peroxy)cyclohexane), t-hexyl peroxy isopropyl monocarbonate, t-butylperoxy-3,5,5- T-butyl peroxy-3,5,5-trimethyl hexanoate, t-butyl peroxy pivalate, cumene peroxy neodymium Cucum peroxy neodecanoate, di-isopropyl benzene hydroperoxide, cumene hydroperoxide, isobutyl peroxide, peroxidation 2, 4-two 2,4-dichlorobenzoyl peroxide, 3,5,5-trimethyl hexanoyl peroxide, octanoyl peroxide, oxidized stearic acid Stearoyl peroxide, succinic peroxide, benzoyl peroxide, 3,5,5-trimethyl hexanoyl peroxide ), benzoyl peroxy toluene, 1,1,3,3-tetramethyl butyl peroxy neodecanoate 1-cyclohexyl-1-methyl ethyl peroxy neodecanoate, di-n-propyl peroxy dicarbonate ), di-isopropyl peroxy carbonate, bis(4-t-butyl cyclohexyl) peroxy dicarbonate, Di-2-ethoxy methoxy peroxy dicarbonate, di(2-ethylhexylperoxy)dicarbonate Di(2-ethyl hexyl peroxy) dicarbonate), dimethoxy butyl peroxy dicarbonate, bis(3-methyl-3-methoxybutylperoxy) dicarbonate Di(3-methyl-3-methoxy butyl peroxy) dicarbonate, 1,1-bis(trihexylperoxy)-3,3,5-trimethylcyclohexane (1,1-bis ( T-hexyl peroxy)-3,3,5-trimethyl cyclohexane), 1,1-bis(t-hexyl peroxy cyclohexane), 1,1 -1,1-bis(t-butyl peroxy-3,3,5-trimethyl cyclohexane), 1,1 -(t-butylperoxy)cyclododecane, 2,2-bis(t-butylperoxy)decane (2,2-bis) (t-butyl peroxy)decane), t-butyl trimethyl silyl peroxide, bis(t-butyl)dimethyl decyl peroxide (bis(t-) Dimethyl) dimethyl silyl peroxide), t-butyl triallyl silyl peroxide, bis(tert-butyl) diallyl decane Peroxides (bis (t-butyl) diallyl silyl peroxide) and tris (tert-butyl) aryl alkyl peroxides silicon (tris (t-butyl) aryl silyl peroxide).

The composition comprising an epoxy resin for the adhesion/bonding layer may comprise at least one of an epoxy resin and an epoxy acrylate. The composition comprising an epoxy resin for the adhesion/bonding layer may further comprise a curing agent or a silane coupling agent. The curing agent can be a latent curing agent. The latent curing agent is an epoxy type heat curing agent or photocuring agent, and may be, but is not limited to, any of the typical epoxy type heat curing agents. For example, the curing agent can be, but is not limited to, at least one selected from the group consisting of imidazole, acid anhydride, amine, hydrazide, cationic curing. And mixtures thereof.

Adhesive/bonding layer 40 can have a thickness of from about 10 microns to about 100 microns. Within this thickness range, the adhesive/bonding layer 40 can sufficiently bond the optical pattern layer 20 to the protective component 10 while providing a thin structure.

Although not shown in FIG. 4, the optical sheet 300 may further include a flat layer between the adhesive/bonding layer 40 and the optical pattern layer 20. The flat layer may have a thickness of from about 2 microns to about 200 microns by considering the transmittance and the effect of planarizing the optical pattern layer. The flat layer may be formed of the same material as the optical pattern layer.

Next, an optical sheet according to another embodiment of the present invention will be described with reference to FIG. Figure 5 is a cross-sectional view of an optical sheet in accordance with still another embodiment of the present invention.

Referring to FIG. 5, an optical sheet 400 according to still another embodiment may further include a base layer 27 between the protective member 10 and the optical pattern layer 20. The optical sheet 400 according to this embodiment is substantially the same as the optical sheet 100 except that the optical pattern layer 20 is formed on the base layer 27.

In the optical sheet 400, the base layer 27 of the optical pattern layer 20 is directly formed on the protective member 10 via an adhesive/bonding layer (not shown). In particular, the protective member 10 can be integrally formed with the base layer 27 via an adhesive/bonding layer. For example, the protective component 10 is attached to the base layer 27 via an adhesive/bonding layer to prevent voids (or air layers) from forming between the protective component 10 and the adhesive/bonding layer and between the adhesive/bonding layer and the base layer 27. The base layer 27 of the optical pattern layer 20 is integrally formed with the protective member 10 to prevent an air layer from being formed therebetween, thereby providing high collimation while improving the color gamut of the optical display. The adhesive/bonding layer is substantially the same as the adhesive/bonding layer described in the above embodiments.

The following description will focus on the process of forming the base layer 27 and the optical pattern layer 20.

A base layer 27 is formed between the optical pattern layer 20 and the protective member 10 to support the optical pattern layer 20 and the protective member 10. The surface of the base layer 27 adjacent to the optical pattern layer 20 may become a light incident plane and the surface of the base layer 27 adjacent to the protective member 10 may become a light exiting plane. The base layer 27 allows light received via the optical pattern layer 20 to travel toward the protective member 10.

The base layer 27 may be formed of an optically transparent resin. In particular, the base layer may comprise at least one of the following: a polycarbonate resin; a polyester resin such as polyethylene terephthalate, poly((methyl) (polymethyl (meth)acrylate) and the like; (meth)acrylic resin; and cyclic polyolefin polymer COP.

The base layer 27 can have a thickness of from about 10 microns to about 300 microns, specifically from about 25 microns to about 100 microns. Within this thickness range, the base layer can be used in an optical display.

Another aspect of the invention is directed to an optical display comprising an optical sheet in accordance with an embodiment of the present invention. Next, an optical display according to an embodiment of the present invention will be described with reference to FIG. Figure 6 is a schematic cross-sectional view of an optical display in accordance with one embodiment of the present invention.

Referring to Figure 6, an optical display 1000 in accordance with one embodiment of the present invention can be a quantum dot (QD) LCD. The QD LCD includes a quantum dot layer formed by replacing the color filter of a typical LCD with a QD element.

Specifically, the optical display 1000 includes a collimating member 1010; a liquid crystal layer 1020 formed on the collimating member 1010 and including a thin film transistor (TFT) 1021; a second polarizer 1030 formed on the liquid crystal layer 1020; An illuminating layer 1040 formed on the second polarizer 1030, wherein the collimating member 1010 can comprise an optical sheet in accordance with an embodiment of the present invention. A QD LCD including an optical sheet according to an embodiment of the present invention allows light having a high degree of collimation to enter the QD element, thereby improving the color gamut of the optical display 1000. For example, a QD LCD can have a color gamut of about 80 or greater than, for example, about 80 to about 100. Within this gamut, QD LCDs provide good image quality.

The liquid crystal layer 1020 is inserted between the second polarizer 1030 and the polarizer of the collimating member 1010 to pass through the light entering the liquid crystal layer 1020 toward the second polarizer 1020 or to block into the liquid crystal layer 1030. Light to form an image. The liquid crystal layer 1020 includes a thin film transistor (TFT) 1021. The light emitted from the collimating member 1010 is guided to the light emitting layer 1040 (such as a quantum dot (QD) layer) or the second polarizer 1030 via an operation of applying or blocking a voltage from the TFT 1021 to the liquid crystal cell layer to realize an image. The liquid crystal layer 1020 includes a liquid crystal cell layer encapsulated between two substrates, wherein the liquid crystal cell layer may include a vertical alignment (VA) mode, an in-plane switching (IPS) mode, and a fringe field switching ( Fringe field switching; FFS) mode or twisted nematic (TN) mode liquid crystal cell.

The second polarizer 1030 can be substantially the same as the polarizer 30 described above, but is not limited thereto. The absorption axis of the second polarizer 1030 is substantially at a right angle (90°) with respect to the absorption axis of the polarizer 30 of the collimating member 1010. The second polarizer 1030 is a separate polarizer rather than the polarizer 30 of the collimating component 1010.

In particular, the second polarizer 1030 is produced by modifying a polyvinyl alcohol film (such as a partially formalized polyvinyl alcohol film with iodine or a dichroic dye). Or dyed with an acetoacetyl group-modified polyvinyl alcohol film, followed by stretching the film in the machine direction (MD). In particular, the second polarizer 1030 can be produced via swelling, dyeing, and stretching. In general, the stretching direction becomes the absorption axis of the second polarizer and becomes the transmission axis with respect to the vertical direction of the stretching direction. In fabricating an integrated optical sheet, when an optical pattern of an optical pattern layer is disposed in the direction of the absorption axis of the polarizer, the optical display can maximize the luminous efficiency of light emitted from the light source and subsequently passing through the light guide plate because In the law, the polarization component is separated from the light passing through the light guide plate, thereby increasing the transmission efficiency of the electric field component reflected by the optical pattern layer. The higher angle between the absorption axis of the polarizer and the arrangement direction of the optical pattern of the optical pattern layer provides a lower transmission efficiency of the electric field, and the right angle between the absorption angle and the arrangement direction of the optical pattern provides the lowest transmission efficiency, thereby reducing the brightness .

The luminescent layer 1040 can include a quantum dot element 1042, a quantum dot element 1043, a quantum dot element 1044, a quantum dot element 1045, and a black matrix 1041.

The quantum dot element 1042, the quantum dot element 1043, the quantum dot element 1044, and the quantum dot element 1045 may correspond to the liquid crystal cells of the liquid crystal layer 1020, and the black matrix 1041 may correspond to the thin film transistor. In particular, the black matrix 1041 may be disposed in a region of the light emitting layer 1040 above the thin film transistor and the quantum dot element 1042, the quantum dot element 1043, the quantum dot element 1044, and the quantum dot element 1045 may be disposed on the light emitting layer 1040. In the area corresponding to the thin film transistor.

Quantum dot elements 1042, quantum dot elements 1043, quantum dot elements 1044, and quantum dot elements 1045 can comprise quantum dots of a particular size. The quantum dots can have a diameter of from about 1 nanometer to about 10 nanometers, specifically from about 2 nanometers to about 8 nanometers. Within this diameter range, the quantum dots can absorb or release light passing through the quantum dot elements and having a particular wavelength to emit certain colors. Compared to typical LCDs, QD LCDs offer excellent capabilities in achieving red and green.

The QD LCD in accordance with the present invention contains quantum dot elements that in turn provide good efficiency in achieving red and green while providing a good white color gamut. In particular, in the structure in which the reverse prism optical pattern according to the present invention is applied to the QD LCD, the QD LCD can exhibit further improvements in color gamut and brightness.

The quantum dot element 1042, the quantum dot element 1043, the quantum dot element 1044, and the quantum dot element 1045 include one or more of a red (R) element, a green (G) element, and a white (W) element. The red (R) element allows red to be illuminated by its light, the green (G) element allows green to be illuminated by its light, and the white (W) element allows white to be illuminated by its light. Color images can be achieved by each of these colors or a combination thereof.

A blue light source can be used as the light source and the quantum dot element can contain no blue elements.

The black matrix 1041 can shield light that is released via the second polarizer 1030. The black matrix 1041 serves to prevent the color of the quantum dot elements adjacent to the corresponding quantum dot elements from being achieved when the non-collimated light passes through the liquid crystal layer 1020.

The light emitting layer 1040 may further include a barrier layer formed on one or both surfaces thereof. The barrier layer may comprise an optically clear film commonly used in the art. For example, the barrier layer may be formed of at least one of: cyclic polyolefin resins, including cyclic olefin polymer COP and the like; poly(meth)acrylic acid Poly(meth)acrylate resins; polycarbonate resins; polyester resins, including polyethylene terephthalate (PET) and the like; cellulose ester resins (cellulose) Ester resins), including triacetyl cellulose and the like; polyethersulfone resins; polysulfone resins; polyamide resins; polyimide resins Resins);polyolefin resins;polyvinyl alcohol resins;polyvinyl chloride resins; and polyvinylidene chloride Resins).

In the QD LCD according to the present invention, light having a high degree of collimation is emitted from the collimating member 1010, thereby providing a good color gamut while reducing the brightness through the width of the black matrix 1041. For example, the black matrix 1041 can have a width of from about 3 microns to about 30 microns, specifically from about 3 microns to about 15 microns. Within this width range, the QD LCD can have a higher brightness.

In the QD LCD according to the present invention, the thicknesses of the liquid crystal layer 1020 and the second polarizer 1030 are determined such that the distance between the TFT 1021 and the quantum dot element 1042, the quantum dot element 1043, the quantum dot element 1044, and the quantum dot element 1045 becomes About 500 microns or less than 500 microns, specifically about 200 microns or less than 200 microns, to further improve the color gamut. Within this range, the QD LCD can have a good color gamut while reducing the brightness through the width of the black matrix 1041.

Although not shown in FIG. 6, optical display 1000 can further include a light guide that directs light emitted from the light source to collimating member 1010. Although not shown in FIG. 6, the optical display 1000 may further include a reflective sheet disposed under the light guiding plate and reflecting light emitted from the light source toward the light guiding plate to improve luminous efficiency.

The light guide plate is used to direct light emitted from the light source into the collimating member 1010 at an angle (θ1) of about 50° to about 85°, specifically about 60° to about 80° with respect to a normal to the plane of incidence of the light. The light guide plate can be a typical light guide plate known to those of ordinary skill in the art.

The reflective sheet can be a typical reflective sheet (reflective or diffusive) known to those of ordinary skill in the art. In particular, in order to improve the light collecting and collimating effect of the optical pattern layer of the collimating member according to the present invention, a reflective reflecting sheet, in particular a Gaussian reflecting sheet, may be used. The reflective reflective sheet applied to the QD LCD can further improve the collimation of the optical sheet, thereby ensuring a good color gamut.

Hereinafter, the present invention will be described in more detail with reference to some examples. However, it is to be understood that the examples are provided for illustration only and are not to be construed as limiting the invention in any way. Example 1

The polarizer was produced by stretching polyvinyl alcohol in an aqueous solution of iodine to 3 times its original length at 60 ° C, followed by further stretching the film to 2.5 times in an aqueous boric acid solution at 40 ° C. In order to form a protective member, a triacetylcellulose (TAC) film (thickness: 80 μm) was attached to a polarizer via a binder (Z-200, Nippon Goshei Co., Ltd.). The upper surface and the lower surface further produce a polarizing plate.

By coating a surface of a polyethylene terephthalate (PET) base layer (T910E, thickness: 125 μm, Mitsubishi Co., Ltd.) with a height of 10 μm (H) An optical pattern of a reverse prism (triangular cross section) between 13 microns (P) and an apex angle (α) of 66° to form a stack structure of the reverse prism optical pattern layer and the base layer.

An adhesive/bonding layer is formed between the polarizing plate and the base layer of the stacked structure to adhere the polarizing plate to the stacked structure to form a collimating member, wherein the reverse prism optical pattern layer is formed directly under the protective member of the polarizer. An adhesive/bonding layer was formed using an adhesive composition comprising 20 parts by weight of methylethylketone, 100 parts by weight of CI-203 (Mw: 1,600,000 g/mole, Tg: -33 ° C, comprehensive research formula) Soken Co., Ltd.), 0.5 parts by weight of an isocyanate curing agent, 0.16 parts by weight of a carbodiimide curing agent, and 0.35 parts by weight of a silane coupling agent.

A light guide plate (46" laser pattern LGP, company H) is placed under the reverse prism optical pattern layer of the collimating member, and a reflective reflection sheet (ESR, 3M) is placed on the lower surface of the light guide plate, and then The brightness (%) determined by the angle at which the light is emitted. The measurement results are shown in Table 1. Here, the blue light emitting diode is used as a light source and the light entering the collimating member has a range of 60° to 80°. Angle of incidence.

In addition, a liquid crystal layer (Samsung Display Co., Ltd.), a polarizer (the same as a polarizer of a polarizing plate), and a light-emitting layer (Samsung Electronics Co., Ltd.) are used. The photodiode is sequentially placed on the polarizer to generate a quantum-dot liquid crystal display (QD LCD), and then the color gamut is measured. The results are shown in Table 1. Example 2

In addition to the use of a diffuse type reflection sheet (TXJ32K, Toray Co., Ltd.), the collimation member and the QD LCD were fabricated in the same manner as in Example 1 and the brightness was measured depending on the angle of incidence of the light. (%) and color gamut. Example 3

The collimation member and the QD LCD were fabricated in the same manner as in Example 1 except that the stack structure was not attached to the protective member via the adhesive/bonding layer, and the brightness (%) and color gamut were determined depending on the angle of incidence of the light. Comparative example 1

By coating each surface of a polyethylene terephthalate (PET) base layer (T910E, thickness: 125 μm, Mitsubishi Corporation) with a height (H) of 25 μm and a pitch of 50 μm (P) An optical pattern of a reverse prism (triangular section) of an apex angle (α) of 90° is used to fabricate a prism sheet. In addition to stacking the two prism sheets manufactured so as to be perpendicular to each other such that the apex of the prism faces the polarizing plate, the collimating member and the QD LCD are fabricated in the same manner as in Example 1 and the brightness (%) is determined by measuring the angle of incidence of the light. Color gamut. Comparative example 2

The collimation member, the QD LCD, and the brightness (%) and the color gamut were measured in the same manner as in Comparative Example 1, except that a diffusing reflection sheet (TXJ32K, Toray Industries, Inc.) was used. Characteristic measurement

(1) Brightness depending on the angle of incidence of light (%): For each of the collimating members (including the light guide plate and the reflection sheet) of the examples and comparative examples, use EZCONTRAST X88RC (EZXL- 176R-F422A4, ELDIM) measures the brightness depending on the angle of incidence of the light. The relative brightness at each viewing angle is calculated by Equation 1 with reference to the viewing angle of 0° (=the normal direction of the light exiting plane). [Equation 1] Relative brightness (%) = depending on the angle of light emission = (brightness at each light emission angle / brightness at (0)) × 100

The light exit angle is the angle defined relative to the normal of the protective layer.

(2) Color gamut (DCI): The color gamut can be measured by the color coordinates (Minolta CS1000, Konica Co., Ltd.) by Digital Cinema Initiatives (DCI) ) said. The color gamut of each of the QD LCDs of the measurement examples and the comparative examples was measured, and the measurement results are shown in Table 1. Table 1

As can be seen from Table 1, the quantum dot (QD) LCD display of each of the examples using an optical sheet in which the protective member is integrally formed with the optical pattern layer configured to collect light toward the quantum dot element is superior to the comparative example. The color gamut of a quantum dot (QD) LCD fabricated using a typical optical sheet. In particular, it can be seen that the side lobes emitting light out of the plane at an angle of ±30° or more than ±30° (θ ₂ ) with respect to the normal to the plane of the light exiting have low brightness, thereby providing high degree of collimation.

7 is a graph depicting the relationship between the luminance (Y) and the angle (X) with respect to the normal to the light exit plane in Example 1 and Comparative Example 1.

In FIG. 7, the QD LCD of Example 1 satisfies the normal of the light exiting the plane at an angle of ±30° or more than ±30° with respect to the normal to the light exit plane (θ ₂ ) as the normal at the light exit plane. The condition that 10% or less of the brightness of the light emitted from the plane is emitted in the direction is not satisfied by the QD LCD of Comparative Example 1.

In Fig. 7, an optical sheet in which the optical pattern layer and the protective member are integrally formed is shown to exhibit good light collimation. However, the optical sheet in which the optical pattern layer is formed on the light exiting plane of the comparative example exhibits poor light collimation.

Further, in Table 1, it can be seen that in the structure in which the protective member is integrally formed with the optical pattern layer to remove the air layer therebetween, the use of the reflection sheet further reduces the side lobe brightness.

Thus, an optical sheet according to the present invention has a high degree of collimation with respect to light exiting the plane from which light exits, and an optical display comprising the same exhibits a good color gamut. Further, the present invention provides a quantum dot liquid crystal display having good characteristics in terms of luminance and color gamut.

Although a few embodiments have been described above, it is to be understood that the present invention is provided by way of illustration only and should not be construed as limiting the invention in any way, and The learner makes various modifications, changes, and changes. Therefore, the scope of the invention should be defined by the scope of the appended claims and their equivalents.

10‧‧‧Protection parts
13‧‧‧Light incident plane
15‧‧‧Light shot out of the plane
20‧‧‧Optical pattern layer
23‧‧‧Reverse prismatic optical pattern layer
27‧‧‧ grassroots
30‧‧‧Polarizer
40‧‧‧Adhesive/bonded layer
100‧‧‧ optical film
200‧‧‧ optical film
300‧‧‧ optical film
400‧‧‧ optical film
1000‧‧‧Optical display
1010‧‧‧ Collimation parts
1020‧‧‧Liquid layer
1021‧‧‧film transistor
1030‧‧‧Second polarizer
1040‧‧‧Lighting layer
1041‧‧‧Black matrix
1042‧‧‧Quantum point components
1043‧‧‧Quantum point components
1044‧‧‧Quantum point components
1045‧‧‧Quantum point components
H‧‧‧ Height
P‧‧‧pitch α‧‧‧apex angle θ ₁ ‧‧‧angle θ ₂ ‧‧‧ angle

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a schematic cross-sectional view of an optical sheet in accordance with one embodiment of the present invention. Fig. 2 is a schematic view showing the relationship between the normal line, the incident angle, and the exit angle. Figure 3 is a schematic cross-sectional view of an optical sheet in accordance with another embodiment of the present invention. 4 is a schematic cross-sectional view of an optical sheet in accordance with another embodiment of the present invention. Figure 5 is a schematic cross-sectional view of an optical sheet in accordance with still another embodiment of the present invention. Figure 6 is a schematic cross-sectional view of an optical display in accordance with one embodiment of the present invention. Fig. 7 is a graph showing the relationship between the luminance (Y) and the light exit angle (X) with respect to the normal to the light exit plane in Example 1 and Comparative Example 1.

10‧‧‧Protection parts

13‧‧‧Light incident plane

15‧‧‧Light shot out of the plane

20‧‧‧Optical pattern layer

30‧‧‧Polarizer

100‧‧‧ optical film

Claims (19)

An optical sheet comprising: a protective member comprising a light incident plane and a light exiting plane facing the light incident plane; an optical pattern layer formed on the light incident plane; and a polarizer formed on the light exiting plane Wherein light is incident on the light incident plane at an angle of from about 50[deg.] to about 85[deg.] with respect to a normal to the plane of incidence of the light, and at a light exit angle at about a normal to the light exit plane The brightness of the side lobes emitting the light exiting plane at an angle of ±30° or more than ±30° is about 10% or less than the brightness of the light that emits the light exiting plane in the normal direction of the light exiting plane. %. The optical sheet of claim 1, wherein the optical pattern layer comprises a plurality of unit prisms continuously disposed thereon, each of the unit prisms having a height of from about 2 micrometers to about 65 micrometers. Between about 5 microns and about 60 microns and an apex angle of from about 50° to about 100°. The optical sheet of claim 1, wherein the optical pattern layer comprises an optical pattern and the optical pattern is disposed in a direction parallel to an absorption axis of the polarizer. The optical sheet of claim 1, wherein the optical pattern layer is integrally formed with the protective member via an adhesive layer or a bonding layer. The optical sheet of claim 4, wherein the light is emitted at an angle of about ±30° or greater than ±30° with respect to the normal to the light exiting plane at the light exit angle. The brightness of the side lobes of the plane is about 5% or less than 5% of the brightness of the light exiting the light exiting plane in the normal direction of the light exiting plane. The optical sheet of claim 1, wherein the optical pattern of the optical pattern layer is disposed in an absorption axis direction of the polarizer. The optical sheet of claim 1, further comprising: a base layer between the protective member and the optical pattern layer. The optical sheet of claim 7, wherein the protective member is integrally formed with the base layer via an adhesive layer or a bonding layer. The optical sheet of claim 2, wherein each of the unit prisms has an apex angle of from about 63° to about 67°. An optical display comprising: a collimating member; a liquid crystal layer formed on the collimating member and including a thin film transistor; a second polarizer formed on the liquid crystal layer; and formed on the second polarizer The light-emitting layer, wherein the collimating member contains the optical sheet as described in claim 1 of the patent application. The optical display of claim 10, wherein the luminescent layer comprises a light emitting device and a black matrix. The optical display of claim 11, wherein the illuminating device comprises a quantum dot element. The optical display of claim 11, wherein the light emitting device comprises at least one of a red component, a green component, and a white component. The optical display of claim 10, wherein the luminescent layer further comprises a barrier layer formed on one or both surfaces thereof. The optical display of claim 10, wherein the optical display has a color gamut of about 80 or greater. The optical display of claim 10, further comprising: a light guide plate disposed under the optical sheet. The optical display of claim 16, further comprising: a reflective sheet disposed under the light guiding plate. The optical display of claim 17, wherein the reflective sheet is a reflective reflective sheet. The optical display of claim 10, wherein the optical display is a quantum dot liquid crystal display.