KR20170117961A - Polarizing plate for oled and optical display apparatus comprising the same - Google Patents

Abstract

The present invention provides a polarizer comprising: a polarizer; A protective film formed on the polarizer; And a laminated body of a? / 4 reverse wavelength dispersive retardation film and a positive C plate formed on the lower portion of the polarizer, and an optical display device including the polarizer.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polarizing plate for OLED, and an optical display device including the polarizing plate.

The present invention relates to a polarizing plate for an OLED (organic light emitting diode) and an optical display device including the same.

The organic light emitting diode (OLED) display device may suffer from deterioration of display performance due to mutual interference between light emitted from the self-luminous body and external natural light (external light) entering from the outside and reflected by the internal reflection plate. To suppress this, the OLED display device includes a polarizing plate.

In general, the polarizing plate for OLED is oriented such that the absorption axis of the polarizer and the optical axis (absorption axis) of the retardation compensation film are inclined. As a result, the waveform of the external light reflected by the internal reflection plate is rotated to have a function as an anti-reflection filter. However, this asymmetric orientation of the absorption axis of the polarizer and the optical axis of the retardation compensation film can cause lateral color shift during OLED driving.

As a method for solving such side color shift phenomenon, it has been attempted to include a polarizing plate in which two retardation films, a biaxially stretched retardation compensation film, an inverse wavelength dispersive film, or a liquid crystal type retardation compensation film are included. OLED polarizers currently in commercial use include a retardation film of? / 4 reverse phase wavelength dispersion of a polycarbonate-based material, but the improvement of side color shift phenomenon is insufficient. That is, as the incident angle increases with respect to the front surface, the color changes to blue or violet color depending on the azimuth angle, or the reflectance increases. This is because the optical path of the external light of the side surface is different from the front surface depending on the incident angle, and the phase delay of RGB occurs.

In this regard, Korean Patent Publication No. 2010-0008203 discloses a liquid crystal display comprising a polarizer, an upper transparent support attached to the upper surface of the polarizer, a compensation film attached to the lower surface of the polarizer, A polarizing plate comprising a polymerizable monomer.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a polarizing plate for OLED which improves the OLED side color shift phenomenon in which the reflection color varies in the lateral direction.

Another object of the present invention is to provide an OLED polarizer capable of being thinned.

It is still another object of the present invention to provide an optical display device including the OLED polarizer.

A polarizing plate for OLED, which is one aspect of the present invention, comprises a polarizer; A protective film formed on the polarizer; And a laminate of a? / 4 reverse wavelength dispersive retardation film and a positive C plate formed on the lower portion of the polarizer.

An optical display device according to another aspect of the present invention may include the polarizing plate for OLED.

The present invention provides an OLED polarizer capable of thin SILM and capable of eliminating the OLED side color shift phenomenon in which the reflection color varies in the lateral direction in the polarizing plate in which the absorption axis of the polarizer and the optical axis of the retardation film are inclined.

1 is a cross-sectional view of a polarizing plate for OLED according to one embodiment of the present invention.
2 is a cross-sectional view of a polarizing plate for OLED according to another embodiment of the present invention.
3 is a cross-sectional view of a polarizing plate for OLED according to another embodiment of the present invention.
4 is a cross-sectional view of an optical display device according to one embodiment of the present invention.
5 is a frontal retardation change value (dotted line: phase difference with respect to the absorption axis of the retardation film, solid line: phase difference with respect to the transmission axis of the retardation film) at an incident angle of -75 DEG to + 75 DEG in the laminate of Example 1 at a wavelength of 550 nm .
6 is a graph showing changes in front retardation (dotted line: phase difference with respect to the absorption axis of the retardation film, solid line: retardation film) of the? / 4 reverse wavelength dispersion retardation compensation film of Comparative Example 1 at a wavelength of 550 nm at an angle of -75 to + The phase difference with respect to the transmission axis).
Fig. 7 is a graph showing the relationship between the? / 4 inverse wavelength dispersion (wavelength) of Comparative Example 1 at Ro (solid line) and lateral azimuth (tilt in units of °) at a wavelength of 550 nm of the laminate of Example 1 at a lateral azimuth And Ro (dotted line) at a wavelength of 550 nm of the retardation compensation film.
8 is a graph showing the relationship between the? / 4 inverse wavelength dispersion retardation of Comparative Example 1 in terms of Rth (solid line) and lateral azimuth (tilt, unit: °) at a wavelength of 550 nm of the laminate of Example 1 at a side azimuth angle And Rth (dotted line) at a wavelength of 550 nm of the compensation film.
9 is a color shift result according to a lateral azimuth angle (unit: °) of the polarizing plate of Example 1. FIG.
10 is a color shift result according to the lateral azimuth angle (unit: °) of the polarizing plate of Comparative Example 1. FIG.

In the present specification, 'upper' and 'lower' are defined with reference to drawings for convenience, and 'upper' may be changed to 'lower' and 'lower' may be changed to 'upper' depending on viewing time.

A polarizing plate for OLED, which is one aspect of the present invention, comprises a polarizer; A protective film formed on the polarizer; And a laminate of a? / 4 reverse wavelength dispersive retardation film and a positive C plate formed on the lower portion of the polarizer.

An OLED panel may be laminated on the lower part of the laminate by an adhesive.

1 and 2 are sectional views of a polarizing plate for OLED according to one embodiment of the present invention.

1, a polarizing plate 100 for an OLED includes a polarizer 105; A protective film 110 laminated on the upper surface of the polarizer 105; A retardation film 115 of λ / 4 reverse phase wavelength dispersion laminated on the lower surface of the polarizer 105; And a positive C plate 120 laminated on the lower surface of the? / 4 reverse wavelength dispersive retardation film 115.

2, the OLED polarizer 200 includes a polarizer 205; A protective film 210 laminated on the upper surface of the polarizer 205; A positive C plate 220 laminated on the lower surface of the polarizer 205; And a? / 4 reverse wavelength dispersive retardation film 215 laminated on the lower surface of the positive C plate 220.

1 and 2, the order of lamination of the? / 4 reverse-wavelength dispersive phase retardation film and the positive C plate among the polarizing plates for OLED is not limited. That is, the lower surface of the polarizer may be in contact with the? / 4 inverse wavelength dispersive phase retardation film of the laminate. Or the lower surface of the polarizer may be in contact with the positive C plate of the laminate.

The laminate can minimize the side color shift phenomenon in which the color varies depending on the lateral direction by minimizing the difference in retardation value between the? / 4 inverse wavelength dispersive phase retarder alone and the retardation value in the frontal retardation. That is, the positive C plate can improve the lateral color shift by minimizing the phase delay difference generated when the optical axis (absorption axis) of the? / 4 reverse wavelength dispersive phase difference film and the absorption axis of the polarizer are inclined.

In a specific example, assuming that the polarizing plate is laminated on the OLED panel, when the front viewing angle is 0 °, the left direction is "-", and the right direction is "+" -75 ° to 0 ° and 0 ° to + 75 °, the retardation difference (Ro) of the retardation film with respect to the transmission axis of the retardation film may be 130 nm to 145 nm. In addition, the laminate may have a retardation difference (Ro) of 145 nm to 165 nm with respect to the absorption axis of the retardation film at a side viewing angle of -75 ° to 0 ° and 0 ° to + 75 ° at a wavelength of 550 nm.

The laminate may have a front retardation (Ro) of 144.4 nm to 150 nm, preferably 144.4 nm to 145 nm at a wavelength of 550 nm. Within this range, side color shift can be improved.

The laminate may have a retardation (Rth _A ) in the thickness direction represented by the following formula 1 at a wavelength of 550 nm of 0 nm to 300 nm and a degree of biaxiality (Nz _A ) represented by the following formula 2 of 0.8 or less. Within this range, Side color shift can be improved:

<Formula 1>

_{Rth A = ((nx A +} ny A) / 2 - nz A) × d A

<Formula 2>

_{Nz A = (nx A - nz} A) / (nx A - ny A)

_{(Wherein, nx A, ny A, nz} A is a refractive index (refractive index), the refractive index of the refractive index and the z-axis direction of the y-axis direction of the x axis, each laminate, d _A is the thickness of the laminate (in nm).

Preferably, Rth _A is from 0 nm to 150 nm, Nz _A is from 0.5 to 0.8, more preferably Rth _A is from 0 nm to 30 nm, and Nz _A is from 0.6 to 0.7.

The laminate may be divided into an x-axis direction which is a machine direction (MD), a y-axis direction which is a transverse direction (TD), and a z-axis direction which is a thickness direction in the laminate.

The laminate can be laminated with an adhesive layer between the? / 4 reverse wavelength dispersive phase retardation film and the positive C plate. The adhesive layer can be formed of an acrylic adhesive or the like, but is not limited thereto.

The layered product may have a thickness of 5 탆 to 100 탆. In the above range, it can be used for a polarizing plate application.

The detailed components of the polarizing plate for OLED of the present invention will be described in detail.

Polarizer

The polarizer may comprise a conventional polarizer having a polarization performance. In a specific example, the polarizer has a function of absorbing linearly polarized light having a vibration plane in a specific direction by adsorbing and orienting a dichromatic dye to a polyvinyl alcohol-based resin, and transmitting the linearly polarized light having a vibration plane perpendicular to the polarized light, A linear polarizer can be used. The dichroic dye may include iodine or a dichroic organic dye.

Normally, the polarizer can be produced by uniaxial stretching of a polyvinyl alcohol-based resin film, dyeing with a dichroic dye, and boric acid treatment after dyeing.

The polarizer may have a thickness of 4 탆 to 30 탆.

Protective film

The protective film is a film made of a transparent resin and is conventionally used as a protective film of a polarizer, and is not particularly limited. In a specific example, the protective film may be formed of a cellulose-based polyester, a cyclic polyolefin, a polycarbonate, a polyether sulfone, a polysulfone, a polyamide, a polyimide, or a polyolefin , A polyarylate film, a polyvinyl alcohol film, a polyvinyl chloride film, and a polyvinylidene chloride film.

The protective film has a thickness of 5 탆 to 100 탆, And can be 5 탆 to 80 탆. In the above range, it can be used as a polarizing plate upon lamination to a polarizer.

The protective film may be laminated to the polarizer by an adhesive layer. In an embodiment, the adhesive layer may include an adhesive layer formed of an aqueous adhesive, a pressure-sensitive adhesive, and a UV-based adhesive. For example, a polyvinyl alcohol-based water-based adhesive.

The protective film may further include a functional layer on one side of the protective film, for example, on top of the protective film. The functional layer may be a hard coating layer, an antireflection layer, or the like. In particular, the hard coat layer can improve the hardness of the polarizing plate by improving the hardness of the protective film. In an embodiment, the functional layer may have a thickness of 1 탆 to 50 탆.

? / 4 reverse wavelength dispersion retardation film

The? / 4 inverse wavelength dispersive phase difference film may be a film having in-plane? / 4 retardation value and reverse wavelength dispersibility. The 'reverse wavelength dispersion property' may mean a front retardation value at a wavelength of 380 nm to 780 nm or a tendency that Nz increases as a wavelength increases, with respect to a front retardation value (Ro) or Nz at a reference wavelength. The reference wavelength may be 550 nm.

The? / 4 inverse wavelength dispersive phase difference film can be combined with a polarizer to provide a function as an antireflection filter for an OLED.

The phase difference film at a wavelength of 550nm, the front retardation (Ro) is 100nm ~ 200nm, to biaxial degree represented by the 0nm ~ 300nm, Equation 4 thickness retardation (Rth _B) represented by the formula 3 (Nz _B) is 0.8 to 1.2, and the in-plane retardation (Re _B ) represented by the following formula 5 may be 100 nm to 200 nm:

<Formula 3>

Rth _B = ((nx _B + ny _B ) / 2 - nz _B ) x d _B

<Formula 4>

Nz _B = (nx _B - nz _B ) / (nx _B - ny _B )

&Lt; EMI ID =

_B = Re _(B nx - ny _B) × d _B

(Note that in the _{above, nx B, ny B, nz} B is the refractive index and the refractive index of the z-axis direction of the refractive index (refractive index), y-axis direction of the x axis, each phase difference film, d _B is the thickness of the retardation film (unit: nm).

The retardation film may be divided into an x-axis direction which is a machine direction (MD) of the retardation film, a y-axis direction which is a transverse direction (TD), and a z-axis direction which is a thickness direction.

In a specific example, assuming that the polarizing plate including the retardation film is laminated on the OLED panel, when the front viewing angle is 0 °, the left direction is '-' and the right direction is '+' At a wavelength of 550 nm, the phase retardation film may have a retardation difference (Ro) of 45 nm to 145 nm with respect to the transmission axis of the retardation film at a side viewing angle of -75 ° to 0 ° and 0 ° to + 75 °.

The retardation film may have a retardation difference (Ro) of 145 nm to 200 nm with respect to the absorption axis of the retardation film at a wavelength of 550 nm and a lateral viewing angle of -75 to 0 and 0 to +75.

Wherein the absorption axis of the polarizer and the optical axis (absorption axis) of the retarder film are in a range of 43 to 47 degrees with respect to each other such that an angle between the absorption axis and the optical axis is 43 to 47 or 133 to 137, Or 133 [deg.] To 137 [deg.].

The retardation film may be laminated to the polarizer by an adhesive layer. In an embodiment, the adhesive layer may include an adhesive layer formed of an aqueous adhesive, a pressure-sensitive adhesive, and a UV-based adhesive. For example, a polyvinyl alcohol-based water-based adhesive.

The retardation film may be a film made of a transparent resin. In embodiments, the retardation film may comprise a film comprising at least one of a polycarbonate (PC) based resin, a cycloolefin polymer (COP) based resin, an acrylic based resin, and a cellulose based resin.

The thickness of the retardation film may be 50 to 100 占 퐉, preferably 50 to 75 占 퐉. In the above range, it can be used for a polarizing plate application.

Positive C plate

The positive C plate is a positive uniaxial optical element means of which the refractive index distribution satisfying the _C nz> nx = ny _{C C.} The retardation film used as the positive C plate may be a solidified layer or a cured layer of a liquid crystal composition containing a liquid crystal compound.

The positive C plate may have an in-plane retardation (Re _C ) of 5 nm or less and a thickness direction retardation (Rth _C ) of -300 to 0 nm as represented by the following formula 7 at a wavelength of 550 nm:

&Lt; EMI ID =

Re _C = (nx _C - ny _C ) xd _C

Equation (7)

_{Rth C = ((nx C +} ny C) / 2 - nz C) × d C

(Wherein, nx _C, ny _C, nz _C is the refractive index of the refractive index and the z-axis direction of the refractive index (refractive index), y-axis direction of the x-axis direction of the positive C plate, d _C is the thickness of the positive C plate ( Unit: nm).

Preferably, Re _C can be from 0 to 5 nm and Rth _C can be from -150 to -50 nm.

The positive C plate is a liquid crystal oriented film, which is commercially available or can be prepared by a conventional method known to a person skilled in the art.

The positive C plate may be divided into an x-axis direction as a liquid crystal coating direction, a y-axis direction as a direction perpendicular to a liquid crystal coating direction, and a z-axis direction as a thickness direction.

The positive C plate may be laminated to the polarizer by an adhesive layer. In an embodiment, the adhesive layer may include an adhesive layer formed of an aqueous adhesive, a pressure-sensitive adhesive, and a UV-based adhesive. For example, a polyvinyl alcohol-based water-based adhesive.

The thickness of the positive C plate may be 0.1 to 10 탆, preferably 1 to 5 탆. In the above range, it can be used for a polarizing plate application.

The polarizing plate may further include an isotropic film as a protective film between the polarizer and the laminate.

Referring to FIG. 3, the polarizing plate 300 for an OLED includes a polarizer 305; A protective film 310 laminated on the upper surface of the polarizer 305; An isotropic film 325 laminated on the lower surface of the polarizer 305; A? / 4 reverse-phase dispersive retardation film 315 laminated on the lower surface of the isotropic film 325; And a positive C plate 320 laminated on the lower surface of the? / 4 reverse wavelength dispersive retardation film 315.

The isotropic film is not limited as long as it is a film capable of protecting the polarizer without affecting the retardation of the? / 4 inverse wavelength dispersive phase difference film and the positive C plate.

In an embodiment, the isotropic film may be a transparent film that is unleveled. For example, it is possible to use a polymer such as a cyclic polyolefin (COP), a cellulose, a polyester, a polycarbonate, a polyether sulfone, a polysulfone, a polyamide, a polyimide, a polyolefin, a polyarylate, Based, polyvinyl chloride-based, and polyvinylidene chloride-based materials.

The isotropic film may have a thickness of 5 탆 to 100 탆, preferably 5 탆 to 80 탆. In the above range, it can be used for a polarizing plate application.

The polarizing plate may have a degree of polarization of 90% or more, preferably 90 to 99.99%. Within this range, it can be used for polarizer applications in OLED devices.

The polarizing plate has a transmittance at a wavelength of 550 nm 38% or more, preferably 40 to 49%. Within this range, it can be used for polarizer applications in OLED devices.

The thickness of the polarizing plate may be 50 탆 to 200 탆, preferably 80 탆 to 130 탆. In the above range, it can be used for a polarizing plate application.

An optical display device according to another aspect of the present invention may include the polarizing plate for OLED. The optical display device may include, but is not limited to, an organic light emitting diode (OLED) display device.

4 is a cross-sectional view of an optical display device according to one embodiment of the present invention.

Referring to FIG. 4, the optical display 400 includes an OLED panel 405; A polarizer 100 laminated on the upper surface of the OLED panel 405; And an adhesive layer 410 formed between the polarizing plate 100 and the OLED panel 405.

Hereinafter, the configuration and operation of the present invention will be described in more detail with reference to preferred embodiments of the present invention. It is to be understood, however, that the same is by way of illustration and example only and is not to be construed in a limiting sense.

Example 1

A polyvinyl alcohol film (PS # 60, manufactured by Kuraray Co., Ltd., thickness before stretching of 60 mu m) was stretched by 6 times in an aqueous solution of iodine at 55 DEG C to obtain a polarizer having a transmittance of 45%. A triacetyl cellulose film (HC TAC (DNP, CHP2S), thickness: 30 mu m) hard-coated on the polarizer was bonded with a polyvinyl alcohol adhesive.

(Re: 0 nm, Rth: -78 nm, thickness: 2 占 퐉) and a? / 4 reverse wavelength dispersive retardation compensation film (Teijin, polycarbonate film, Re: Re: 145 nm, Rth: 100 nm, Nz: 1.2, thickness: 50 占 퐉) were adhered with an acrylic adhesive to prepare a laminate. retardation compensation film is oriented so that the optical axis (absorption axis) of the? / 4 reverse-wavelength-dispersive retardation compensation film and the absorption axis of the polarizer are mutually at 45 °, and the polarizer and the? / 4 reverse wavelength dispersion retardation compensation film are brought into contact with each other. A laminate was adhered to the lower part of the polarizer, thereby producing the polarizing plate of Fig.

Example 2

The polarizing plate of Fig. 2 was produced in the same manner as in Example 1 except that the polarizer and the positive C plate were brought into contact with each other.

Comparative Example 1

A polyvinyl alcohol film (PS # 60, manufactured by Kuraray Co., Ltd., thickness before stretching of 60 mu m) was stretched by 6 times in an aqueous solution of iodine at 55 DEG C to obtain a polarizer having a transmittance of 45%. A triacetyl cellulose film (HC TAC (DNP, CHP2S), thickness: 30 mu m) hard-coated on the polarizer was bonded with a polyvinyl alcohol adhesive. Retardation compensation film (Teijin, polycarbonate-based film, wavelength: 550 nm) was laminated on the lower portion of the polarizer so that the optical axis of the? / 4 inverse wavelength dispersive phase retardation compensation film and the absorption axis of the polarizer were mutually at 45 degrees. Re: 145 nm, Rth: 100 nm, Nz: 1.2) was bonded with an acrylic adhesive to prepare a polarizing plate.

Comparative Example 2

A polyvinyl alcohol film (PS # 60, manufactured by Kuraray Co., Ltd., thickness before stretching of 60 mu m) was stretched by 6 times in an aqueous solution of iodine at 55 DEG C to obtain a polarizer having a transmittance of 45%. A triacetyl cellulose film (HC TAC (DNP, CHP2S), thickness: 30 mu m) hard-coated on the polarizer was bonded with a polyvinyl alcohol adhesive. A positive C plate (JX, NV80, Re: 0 nm at a wavelength of 550 nm, Rth: -78 nm) was bonded to the bottom of the polarizer with an acrylic adhesive to prepare a polarizing plate.

The resulting polarizing plate was assembled on a single article or an OLED panel, and physical properties were evaluated. The results are shown in Figs. 5 to 10.

(1) Transmittance (Ts) and degree of polarization (P.E): The polarizing plate was measured using V-7100 (JASCO, Japan).

(2) retardation property: A laminate of a positive C plate of 50 mm x 50 mm (width x length) and a quarter wavelength retardation compensation film or a retardation film of? / 4 reverse wavelength dispersion retardation film alone, And the retardation characteristics were measured at a wavelength of 550 nm.

(3) Reflectance and color shift: A polarizing plate was laminated on an OLED panel, and reflectance and color change values at a lateral azimuth angle of a predetermined range and a wavelength of 550 nm were measured using an EZ-contrast three-dimensional measuring device (Eldim, France).

division Polarizer thickness (탆) Shape Transmittance (%) Polarization degree (%) reflectivity(%) Nz Remarks Example 1 112 44.8 99.2 4.8 0.67 - Example 2 112 44.8 99.2 4.8 0.67 - Comparative Example 1 107 44.8 99.2 5.0 1.2 - Comparative Example 2 57 44.8 99.2 25 0.5 Antireflection filter function

As shown in Table 1 and FIG. 5 to FIG. 10, the polarizing plate of the present invention minimizes the retardation value in the thickness direction in the lateral azimuth angle as shown in FIGS. 5 and 8, thereby improving the side color saturation and minimizing the side color shift phenomenon This can be seen from the results of FIG.

On the other hand, in the polarizing plate of Comparative Example 1 which does not include the positive C plate, as shown in FIGS. 6 and 8, the retardation value in the thickness direction in the lateral direction is remarkably larger than that of the present invention, This can be seen from the results of FIG.

In addition, the polarizing plate of Comparative Example 2, which does not include the? / 4 reverse wavelength dispersive retardation film, has a problem of failing to exhibit the function of the antireflection filter.

It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims (16)

A polarizer; A protective film formed on the polarizer; And a laminated body of a? / 4 reverse wavelength dispersive retardation film and a positive C plate formed on the lower portion of the polarizer.
The polarizing plate for OLED according to claim 1, wherein the? / 4 inverse wavelength dispersive retardation film is in contact with the polarizer.
The polarizing plate for OLED according to claim 1, wherein the positive C plate is in contact with the polarizer.
The OLED polarizing plate according to claim 1, wherein the laminate has a retardation (Rth _A ) in the thickness direction represented by the following formula (1) at a wavelength of 550 nm of 0 nm to 300 nm:
<Formula 1>
_{Rth A = ((nx A +} ny A) / 2 - nz A) × d A
_{(Wherein, nx A, ny A, nz} A is a refractive index (refractive index), the refractive index of the refractive index and the z-axis direction of the y-axis direction of the x axis, each laminate, d _A is the thickness of the laminate (in nm).
The OLED display according to claim 1, wherein the laminate has a biaxiality (Nz _A ) expressed by the following formula (2) at a wavelength of 550 nm of 0.8 or less:
<Formula 2>
_{Nz A = (nx A - nz} A) / (nx A - ny A)
(Wherein, _A nx, ny _{A, A} nz is the refractive index and the refractive index of the z-axis direction of the refractive index (refractive index), y-axis direction of the x-axis direction of the laminate).
The polarizing plate for OLED according to claim 1, wherein the absorption axis of the polarizer and the optical axis (absorption axis) of the retardation film are oriented at 43 ° to 47 ° or 133 ° to 137 ° with respect to each other.
The polarizing plate for OLED according to claim 1, wherein the laminate has a thickness of 5 탆 to 100 탆.
The retardation film according to claim 1, wherein the? / 4 inverse wavelength dispersive phase retardation film has a thickness direction retardation (Rth _B ) of 0 to 300 nm and a biaxiality degree (Nz _B ) represented by the following formula Polarizing plate for OLED having 0.8 to 1.2:
<Formula 3>
Rth _B = ((nx _B + ny _B ) / 2 - nz _B ) x d _B
<Formula 4>
Nz _B = (nx _B - nz _B ) / (nx _B - ny _B )
(Note that in the _{above, nx B, ny B, nz} B is the refractive index and the refractive index of the z-axis direction of the refractive index (refractive index), y-axis direction of the x axis, each phase difference film, d _B is the thickness of the retardation film (unit: nm).
The polarizing plate for OLED according to claim 1, wherein the? / 4 inverse wavelength dispersive phase retardation film comprises at least one of a polycarbonate (PC) based resin, a cycloolefin polymer (COP) based resin, an acrylic based resin and a cellulose based resin.
The positive C plate according to claim 1, wherein the positive C plate has an in-plane retardation (Re _C ) of 5 nm or less and a thickness direction retardation (Rth _C ) represented by the following formula 6 at a wavelength of 550 nm, Polarizer for OLED:
&Lt; EMI ID =
Re _C = (nx _C - ny _C ) xd _C
&Lt; EMI ID =
_{Rth C = ((nx C +} ny C) / 2 - nz C) × d C
(Wherein, nx _C, ny _C, nz _C is the refractive index of the refractive index and the z-axis direction of the refractive index (refractive index), y-axis direction of the x-axis direction of the positive C plate, d _C is the thickness of the positive C plate ( Unit: nm).
The protective film according to claim 1, wherein the protective film is at least one selected from the group consisting of triacetylcellulose, polyester, cyclic olefin polymer, polycarbonate, polyether sulfone, polysulfone, polyamide, polyimide, polyolefin, A polyvinyl alcohol-based, a polyvinyl chloride-based, and a polyvinylidene chloride-based polarizer.
The OLED polarizing plate according to claim 1, further comprising a hard coating layer on the protective film.
The polarizing plate for OLED according to claim 1, further comprising an isotropic film between the polarizer and the laminate.
14. The method of claim 13, wherein the isotropic film is one selected from the group consisting of cyclic olefin polymer (COP), cellulose, polyester, polycarbonate, polyether sulfone, polysulfone, polyamide, polyimide, A polarizing plate for OLED comprising at least one of polyarylate, polyvinyl alcohol, polyvinyl chloride, and polyvinylidene chloride.
The polarizing plate for OLED according to claim 1, wherein the polarizing plate for OLED has a thickness of 80 탆 to 130 탆.
An optical display device comprising the OLED polarizing plate according to any one of claims 1 to 15.

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