KR20190102694A - Polarizing element for organic light emission display devices - Google Patents

Abstract

The present invention relates to a polarizing element for an organic light emitting display, and an organic light emitting display device capable of switching to which the same is applied. To this end, the polarizing element for an organic light emitting display of the present invention, which is operated by an electric field, comprises: a lower substrate and an upper substrate arranged in opposition to each other; a first electrode and a second electrode arranged between the lower substrate and the upper substrate; and a first horizontal orientation film and a second horizontal orientation film arranged between the first electrode and the second electrode. Here, a liquid crystal mixture solution composed of dichroic dye and liquid crystal is filled between the first horizontal orientation film and the second horizontal orientation film. In addition, the orientation movement of the dichroic dye and the liquid crystal is controlled corresponding to the condition of external light after an electric field is applied between the first electrode and the second electrode, such that the organic light emitting display device to which the polarizing element is applied can reversibly control the reflectivity of the external light and the transmissivity of transmitted light.

Description

Polarizing element for organic light emitting display {POLARIZING ELEMENT FOR ORGANIC LIGHT EMISSION DISPLAY DEVICES}

The present invention relates to a polarizing element for an organic light emitting display, and more particularly, a first electrode and a second electrode, and the first electrode and the first substrate between the lower substrate and the upper substrate, the lower substrate and the upper substrate disposed to face each other. A polarizing element filled with a liquid crystal mixed solution consisting of a dichroic dye and a liquid crystal is provided between a first horizontal alignment layer and a second horizontal alignment layer, the first horizontal alignment layer, and a second horizontal alignment layer between two electrodes. By controlling the orientation behavior of the dichroic dye and the liquid crystal by applying an electric field between the second electrode and the second electrode, the organic light emitting display device to which the same is applied is driven by an electric field capable of reversibly controlling the reflectance of the external light and the transmittance of the transmitted light. The present invention relates to a display polarizer and a switchable organic light emitting display device.

Polarizing plates are used in image display devices such as liquid crystal displays (LCDs) and plasma display panels (PDPs). In particular, polarizing plates are also used in the organic light emitting display devices (OLEDs) to prevent reflection of external light.

Recently, an image display device using a polarizing plate is used for display panels of televisions, monitors, automobile dashboards, computers, notebooks, PDAs, telephones, TVs, audio / video devices, various office and industrial machines.

As the use area of the image display device expands, it is often used for a long time under severe conditions such as high temperature and high humidity. Therefore, in such a harsh environment, excellent durability to provide an image having excellent color reproducibility, which is an original function of the polarizing plate, is provided. And high transmittance and polarization.

Such a polarizing plate is prepared by dyeing and crosslinking a conventional polyvinyl alcohol-based film using a dichroic iodine or a dichroic dye or the like, and then stretching the film into a film in one direction to orient the dichroic dye. A polarizing plate using iodine as a dichroic dye is called an iodine polarizing plate, while a polarizing plate using an organic dye having dichroism as a dichroic dye is called a dye polarizing plate.

Among them, the iodine polarizing plate is excellent in optical properties, but its heat resistance is generally known. Therefore, it has been pointed out that the iodine polarizing plate is difficult to use in an environment requiring high durability.

On the other hand, the dye-based polarizing plate has a high heat resistance, high humidity heat durability and high stability, and also has a feature of high color selectivity by the combination of pigments. However, there is another problem of low polarization performance and contrast compared to iodine polarizers, and thus, a polarizer having high durability, high color selectivity, and higher contrast and high polarization characteristics are required in the related field. do.

Looking at the structure of the OLED, the lower electrode and the upper electrode exist, and the organic light emitting layer is interposed therebetween. In this case, the lower electrode uses a metal plate such as aluminum. Therefore, the lower electrode of the OLED serves as a reflection plate, which greatly reduces the visibility when the external light is strong, such as outdoors, and uses the film type polarizer and l / 4 film mentioned above. However, since the film polarizer absorbs more than 50% of the light emitted from the OLED, there is a problem in that the light efficiency is greatly reduced.

Thus, the present inventors have tried to improve the conventional problems, the polarizer is attached to the film form, the orientation is already fixed, there is a limit to improve the outdoor visibility or transmittance according to the conditions of the external light, but the present invention is a dichroic dye and nematic liquid crystal The mixed dichroic mixture is filled between the first electrode and the second electrode disposed to face each other, and an electric field is applied between the first electrode and the second electrode to vertically and horizontally align the dichroic dye and the nematic liquid crystal. Provides a polarizing element that controls the behavior of the light, and when the external reflection is small, the electric field is applied to the polarizing element using the dichroic dye, and the dichroic dye is placed vertically on the substrate to transmit 70% or more of the light emitted from the organic light emitting display device. By reducing the intensity of the external reflected light to increase the outdoor visibility and confirm that the light efficiency of the polarizing element can be increased in a special situation, The completion of the person.

Republic of Korea Patent No. 1663895 (2016.09.30) Japanese Patent No. 3739396 (Nov.11, 2005) U.S. Patent No. 6606138 (2003.08.12)

It is an object of the present invention to provide a polarizing element for an organic light emitting display containing a dichroic dye driven by an electric field.

Another object of the present invention is to provide an organic light emitting display device which can be switched by applying the polarization element for the organic light emitting display and reversibly adjusting the reflectance of the external light and the transmittance of transmitted light according to the external light intensity.

In order to achieve the above object, the present invention is a lower electrode (11, 21, 31, 41) and the upper substrate (18, 28, 38, 48) and the first electrode disposed between the lower substrate and the upper substrate (12, 22, 32, 42) and the second electrode (17, 27, 37, 47), the first horizontal alignment layer (13, 23, 33, 43) and the second horizontal between the first electrode and the second electrode Liquid crystal consisting of dichroic dyes 14, 24, 34, 44 and liquid crystals 15, 25, 35, 45 between the alignment films 16, 26, 36, 46, the first horizontal alignment film and the second horizontal alignment film. Provided is a polarizing element (10, 20, 30, 40) filled with a mixed solution, the polarizing element capable of changing the orientation of the dichroic dye and the liquid crystal by applying an electric field between the first electrode and the second electrode.

The liquid crystal used in the polarizing element of the present invention is preferably a nematic liquid crystal.

In addition, since the dichroic dye is contained in an amount of 0.5 to 10% by weight with respect to the liquid crystal mixed solution, the behavior of the dichroic dye and the liquid crystal can be controlled in a homeotropic or horizontal orientation by applying an electric field.

The polarizing device of the present invention is any one of an alignment structure in which a liquid crystal mixed solution composed of a dichroic dye and a liquid crystal is filled in a horizontal alignment (Homogeneous), a horizontal alignment in a dual domain, or a vertical alignment (Homeotropic).

In addition, the first electrode and the second electrode in the above-described alignment structure is characterized in that the electrode.

In this case, the first electrode and the second electrode are a transparent conductive material, and the lower substrate and the upper substrate use a transparent substrate.

In addition, the present invention provides an organic light emitting display device that is switchable by stacking a l / 4 phase delay film and the polarizers 10, 20, 30, and 40 on the OLED.

In the switchable organic light emitting diode display device of the present invention, the polarization element 10 is applied with an electric field so that the intensity and the intensity of the external light may be changed through the homeotropic or horizontal alignment of the dichroic dye and the liquid crystal. Depending on the conditions, it is possible to reversibly adjust the reflectance of the external light and the transmittance of the transmitted light.

The present invention fills a dichroic mixture in which a dichroic dye and a nematic liquid crystal are mixed between a first electrode and a second electrode disposed to face each other, and applies an electric field between the first electrode and the second electrode. A polarization device which controls the behavior of homeotropic and horizontal alignment of the dichroic dye and nematic liquid crystal can be provided.

Particularly, the present invention applies an electric field to a polarizing device using a dichroic dye when external reflection is low, and sets the dichroic dye vertically on a substrate to transmit 70% or more of the light emitted from the organic light emitting display device. Compared to the organic light emitting display using the film, the transmittance is significantly improved.

Furthermore, the present invention applies a polarizing device for an organic light emitting display, but by controlling the orientation behavior of the dichroic dye and the liquid crystal according to the application of the electric field, the reflectivity of the external light and the transmittance of the transmitted light can be reversibly controlled according to the conditions. Therefore, an organic light emitting display device capable of switching can be provided.

Accordingly, the polarizer of the present invention can selectively control external reflected light by controlling transmittance and increase the efficiency of the front transmitted light to increase the lifespan of the organic light emitting display device. In detail, outdoor visibility may be reduced by reducing the intensity of external reflected light, and light efficiency of the polarizer may be improved in a special situation, thereby increasing the lifespan of the organic light emitting display device.

1 is a schematic cross-sectional view of an organic light emitting display device in which a conventional reflection reducing film 100 is stacked.
2 is a schematic cross-sectional view of a polarizing element 10 for an organic light emitting display containing a dichroic dye and a liquid crystal driven by an electric field of the present invention.
FIG. 3 is an organic light emitting display device in which a horizontally oriented dichroic dye 14 and a polarizing element 10 using a liquid crystal 15 are stacked in accordance with a first embodiment of the present invention. Shown,
4 illustrates transmission of internal light when external reflection is large with respect to the OLED display of FIG. 3.
FIG. 5 illustrates the transmission of internal light in a state in which the dichroic dye 14 and the liquid crystal 15 are converted to the vertical alignment by the application of an electric field when the external reflection is low, for the organic light emitting display device of FIG. 3.
FIG. 6 is an organic light emitting display device in which a dichroic dye 24 and a liquid crystal 25 using a dichroic dye horizontally oriented in a double domain according to a second embodiment of the present invention are applied, and reflects when external reflection is large. Showing prevention,
FIG. 7 illustrates transmission of internal light when external reflection is large with respect to the OLED display of FIG. 6.
FIG. 8 illustrates the transmission of internal light in a state in which the dichroic dye 24 and the liquid crystal 25 are converted to the vertical alignment by the application of an electric field when there is little external reflection with respect to the organic light emitting display of FIG. 6.
FIG. 9 is an organic light emitting display device to which a polarization element 30 using a dichroic dye 34 and a liquid crystal 35, which are vertically oriented, with a pretilt angle according to a third embodiment of the present invention, is applied. Shows the transmission of internal light,
FIG. 10 illustrates antireflection in a state in which the dichroic dye 34 and the liquid crystal 35 are converted to the horizontal orientation by the application of an electric field when the external reflection is large for the organic light emitting display of FIG. 9.
FIG. 11 illustrates the internal light transmission in the state where the dichroic dye 34 and the liquid crystal 35 are converted to the horizontal orientation by the application of an electric field when the external reflection is large for the organic light emitting display device of FIG. 10.
FIG. 12 shows an organic light emitting display device in which a dichroic dye 44 and a polarizer 40 using a liquid crystal 45 are vertically oriented on the patterned electrodes 42 and 47 according to the fourth embodiment of the present invention. Shows the transmission of internal light when there is little external reflection
FIG. 13 illustrates antireflection in a state in which the dichroic dye 44 and the liquid crystal 45 are converted to the horizontal orientation by the application of an electric field when the external reflection is large for the organic light emitting display device of FIG. 12.
FIG. 14 illustrates the principle of transmission of internal light in a state in which the dichroic dye 44 and the liquid crystal 45 are converted to the horizontal alignment by the application of an electric field when the external reflection is large for the organic light emitting display device of FIG. 12.
FIG. 15 is a photograph of an external reflection blocking mode and a transmission mode during reflection blocking through an organic light emitting display device in which the conventional reflection reducing film of FIG. 1 is stacked;
FIG. 16 is a photograph of an external reflection blocking mode and a transmission mode during reflection blocking through the organic light emitting display device in which the polarization elements of the first embodiment of FIG. 3 are stacked;
FIG. 17 is a photograph of observing a transmission mode through an organic light emitting display device in which a polarizer having a change in orientation by application of an electric field is stacked in the first embodiment of FIG. 5;
18 is a front transmittance result of 100% of transmitted light of the organic light emitting display device of FIGS. 1, 3, and 5.

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

1 is a schematic cross-sectional view of an organic light emitting display device in which a conventional reflection reducing film 100 is stacked. Specifically, the cathode 121 is made of aluminum, the OLED 120 consisting of the photoactive layer 122, the anodes (ITO, 123) and the glass substrate 124, the l / 4 phase delay film 110 and reflection reduction It is a structure laminated with the type | mold film 100.

At this time, since the OLED 120 uses aluminum as the cathode, the lower substrate serves as a reflector. In this case, when external light is strong and the light reflected from the lower substrate is strong, the light emitted from the light emitting layer of the OLED element is distorted. This reduces the visibility and causes a problem in that transmitted light is not seen. In order to overcome this problem, one polarizer and a λ / 4 phase delay film (110, Quarterwave plate) are used.

In addition to the above method, an optical element in which a wide quarter wave plate (λ / 4, λ / 2 film) is laminated at a specific angle may be used.

However, there is a disadvantage that the efficiency is not good for the reflection of the side light other than the front light and the loss of the transmitted light is at least 50%.

In addition, when the reflection reducing film 100 is attached, it is difficult to switch due to external light due to the fixed orientation on the film, and the improvement of light loss cannot be solved.

Accordingly, the present invention replaces the organic light emitting display device by replacing the reflection reducing film 100 of FIG. 1 with the polarizing elements 10, 20, 30, and 40 for the organic light emitting display containing a dichroic dye driven by an electric field. Complete

Below. In the polarizing element for an organic light emitting display, an alignment structure in which a liquid crystal mixed solution composed of a dichroic dye and a liquid crystal is filled in the polarizing element structure of the polarization element 10 of the first embodiment and the second embodiment The polarization element 20 of the horizontal orientation in the dual domain, the homeotropic polarization element 30 of the third embodiment, the first electrode and the second electrode of the fourth embodiment are patterned electrodes, The polarizer 40 will be described.

The polarizing element of the organic light emitting display of the present invention may serve as a polarizing plate used in the prior art by using a dichroic dye, and when the polarized light is not desired, a control that may improve the light efficiency through induction of an orientation using voltage. In the present invention, the behavior of the liquid crystal and the dichroic dye according to voltage application can be adjusted to bring about changes in front transmittance and side reflected light.

At this time, the dichroic dye used in the present invention exhibits the behavior of the horizontal (Homogeneous) and vertical (Homeotropic) according to the orientation, and in the case of the horizontal alignment may serve as a polarizer for absorbing light in a specific direction, front and side The reflected light can be reduced. In addition, in the vertical alignment, the efficiency of transmitted light is maximized and the side reflected light can be reduced.

Fig. 2 is a schematic cross-sectional view of a polarizing element 10 for an organic light emitting display of a first embodiment containing a dichroic dye driven by an electric field of the present invention, applying an alignment technique of a liquid crystal and using an orientation of the liquid crystal. Depending on the application it is possible to control the orientation of the dichroic dye. In this case, when the alignment behavior of the dichroic dye and the liquid crystal is vertically aligned, the usefulness can be applied as a film for protecting personal information by utilizing the property that the transmittance is lower as the observation angle increases.

Therefore, by adjusting the orientation behavior of the dichroic dye and the liquid crystal according to the application of the electric field, not the orientation behavior fixed to the film, the reflectance of the external light and the transmittance of the transmitted light can be reversibly controlled according to the conditions.

Specifically, the lower substrate 11 and the upper substrate 18 disposed opposite to each other, the lower substrate and the upper portion, will be described in detail with reference to the polarization element 10 for the organic light emitting display shown in FIG. The first electrode 12 and the second electrode 17 between the substrate, the first horizontal alignment layer 13 and the second horizontal alignment layer 16, the first horizontal alignment layer and the first electrode between the first electrode and the second electrode Between the two horizontal alignment films, a liquid crystal mixed solution composed of the dichroic dye 14 and the liquid crystal 15 is filled, and the dichroic dye 14 and the liquid crystal 15 are applied by applying an electric field between the first electrode and the second electrode. Orientation behavior is controlled.

Accordingly, the polarizing element 10 of the first preferred embodiment of the present invention is characterized in that the dichroic dye 14 and the liquid crystal 15 are horizontally aligned in the polarizing element structure for the organic light emitting display shown in FIG. .

FIG. 3 shows an organic light emitting display device in which a horizontally oriented dichroic dye 14 and a polarizing element 10 using the liquid crystal 15 are stacked in accordance with a first embodiment of the present invention. The 1/4 phase delay film 110 and the OLED 120 are the same as the organic light emitting display device of FIG.

The dichroic dye 14 and the liquid crystal in which external light is horizontally oriented through the upper substrate 18, the second electrode 17, and the second horizontal alignment layer 16 of the polarizer 10 while no electric field is applied. When the light enters the filled region, light transmitted in the horizontal direction is absorbed and sequentially passes through the second horizontal alignment film 13, the second electrode 12, and the upper substrate 11 oriented in the direction of the arrow. do.

Thereafter, the light direction is reversed in the horizontal direction while passing through the l / 4 phase delay film 110 and the OLED 120, and the polarizing element 10 using the dichroic dye 14 and the liquid crystal 15 which are horizontally oriented again. By passing through), the reflection of light is realized when the external reflection is large.

FIG. 4 illustrates the transmission of internal light when the external reflection is large with respect to the organic light emitting display of FIG. 3, wherein the internal light travels through the OLED 120 and the l / 4 phase delay film 110 without changing the intensity or direction of light. However, when passed to the polarizing element 10 using the horizontally oriented dichroic dye 14 and the liquid crystal 15 of the first embodiment is absorbed and transmitted by the dichroic dye 14 in the horizontal direction.

FIG. 5 illustrates that the voltage V is applied between the first electrode 12 and the second electrode 17 in the organic light emitting display device of FIG. 3, between the first electrode 12 and the second electrode 17. An electric field is applied to the liquid crystal mixed solution consisting of the dichroic dye 14 and the liquid crystal 15 in the liquid crystal mixture.

As such, when an electric field is applied to the liquid crystal mixed solution, the dichroic dye 14 and the liquid crystal 15 are aligned in a direction parallel to the electric field, that is, in a direction perpendicular to the first and second substrates 11 and 18. In other words, the dichroic dye 14 is also aligned in the same direction as the liquid crystal according to the alignment of the liquid crystal 15 having electrical characteristics.

As described above, when the dichroic dye 14 and the liquid crystal 15 are converted to the vertical alignment by applying an electric field, even when there is little external reflection, the internal light passes without changing the intensity or direction of the light, thereby improving transmittance. 18].

Accordingly, the polarizing element 20 of the second preferred embodiment of the present invention has a structure in which the dichroic dye 24 and the liquid crystal 25 are horizontally oriented in the double domain in the polarizing element structure for the organic light emitting display shown in FIG. It is characterized by.

The polarizing element 20 of the second embodiment described above is multi-oriented in order to reduce the viewing angle dependency, and the angle between the rubbing direction of the horizontal alignment layers 23 and 26 and the l / 4 phase delay film 110 is 45 degrees or more. I must go. At this time, if the angle difference is less than 45 degrees, or more than 45 degrees, in particular more than 90 degrees, it is not preferable because it is out of the optimized value in the viewing angle.

FIG. 6 illustrates an organic light emitting display device employing a polarizing element 10 using a dichroic dye horizontally oriented with a dual domain of a second embodiment of the present invention, and implements antireflection when large external reflection is provided . FIG. 7 illustrates the transmission of internal light when the external reflection is large for the organic light emitting display device of FIG. 6.

FIG. 8 illustrates that when the dichroic dye 24 and the liquid crystal 25 are converted to the vertical alignment with respect to the organic light emitting display device of FIG. 6, when the external reflection is small, the internal light passes through the light without changing the intensity or direction of the light. Therefore, the transmittance is improved.

In this case, when the multi-domain is used in the polarizer 10 using the dichroic dye horizontally oriented with the dual domain of the second embodiment to reduce the viewing angle dependency, not only rubbing but also patterning of the electrode may be applied.

The polarizing element 30 of the third preferred embodiment of the present invention contains the dichroic dye 34 and the liquid crystal 35 which are vertically aligned while having a pretilt angle in the polarizing element structure for the organic light emitting display shown in FIG. Structure.

In this case, as shown in FIG . 9 , the organic light emitting display device to which the polarization element 30 of the third embodiment is applied shows transmission of internal light when there is little external reflection, and FIG. 10 shows organic light emitting display of FIG. 9. When the external reflection of the display device is large, the dichroic dye 34 and the liquid crystal 35 may be converted to a horizontal alignment by applying an electric field, thereby preventing reflection of light.

In addition, FIG. 11 may reduce the transmittance of internal light by converting the dichroic dye 34 and the liquid crystal 35 into a horizontal alignment by applying an electric field when the external reflection is large with respect to the organic light emitting display device of FIG. 10.

Further, the polarizing element 40 of the fourth preferred embodiment of the present invention has a structure in which the dichroic dye 44 and the liquid crystal 45 are vertically aligned in the polarizing element structure for the organic light emitting display shown in FIG. The first electrode 42 and the second electrode 47 are formed of a patterned electrode. By providing the patterned electrode, the viewing angle dependency can be reduced.

FIG. 12 illustrates the transmission of internal light for the organic light emitting display device to which the polarization element of the fourth embodiment is applied. Even when there is little external reflection, the transmittance will be improved without passing through the intensity and direction of the internal light.

FIG. 13 may prevent reflection of light by converting the dichroic dye 44 and the liquid crystal 45 into a horizontal alignment by applying an electric field when the external reflection is large with respect to the organic light emitting display device of FIG. 12.

In addition, in FIG. 14 , when the external reflection of the organic light emitting display device of FIG. 12 is large, the transmittance can be controlled by converting the dichroic dye 44 and the liquid crystal 45 into a horizontal alignment by applying an electric field.

In the above-mentioned organic light emitting display polarizing elements 10, 20, 30, 40, it is preferable that a liquid crystal uses a nematic liquid crystal.

The nematic liquid crystal molecules are arranged neatly in the long axis direction but are not layered and have irregular positions.

In addition, the dichroic dyes (14, 24, 34, 44) are preferably contained in an amount of 0.5 to 10% by weight, preferably 0.5 to 5% by weight, more preferably 0.8 to 2% by weight relative to the liquid crystal mixed solution. Do. The dichroic dye content is determined by the electric field applied to the orientation of the dichroic dye and the liquid crystal in the homeotropic or horizontal orientation (Homogeneous), and the range determined experimentally in order to optimize the reflectance of the external light and transmittance of the transmitted light As a content of less than 0.5% by weight, the reflection of the reflected light is not properly absorbed, and thus the reflection blocking effect is low, which is not preferable.

At this time, the dichroic dye used in the present invention can be used without particular limitation as long as the compound having an absorption wavelength of visible light full wavelength band, that is, 400nm to 800nm band, more preferably a compound based on azo, anthraquinone series Can be used. The dichroic dye used in the present invention is suitable for a compound having a characteristic of dissolving in a nematic liquid crystal to form a stable phase, following the orientation of the nematic liquid crystal, and having a difference in light absorptivity depending on the direction.

Such dichroic dyes exhibit the behavior of horizontal (Homogeneous) and vertical (Homeotropic) depending on the orientation, and in the case of the horizontal alignment may act as a polarizer for absorbing light in a specific direction, it is possible to reduce the front and side reflected light. In addition, in the vertical alignment, the efficiency of transmitted light is maximized and the side reflected light can be reduced.

In addition, in the polarization elements 10, 20, 30, and 40 for the organic light emitting display of the present invention, the first electrodes 12, 22, 32, and 42 and the second electrodes 17, 27, 37, and 47 are transparent. The lower substrates 11, 21, 31, 41 and the upper substrates 18, 28, 38, and 48 may use a transparent substrate, and among the materials known in the art, transparent conductive materials and transparency may be used. The substrate material with excitation can be employed without particular limitation.

From the above, the l / 4 phase delay film 110 and the polarizing elements 10, 20, 30, and 40 of the first to fourth embodiments are stacked on the OLED 120, and the organic light is switchable. A light emitting display device is provided.

At this time, the switchable organic light emitting display device is a polarizing element (10, 20) filled with a mixed solution consisting of a dichroic dye (14, 24, 34, 44) and liquid crystals (15, 25, 35, 45) according to the external light , 30, 40) by applying an electric field to the vertical orientation (Homeotropic) or horizontal orientation (Homogeneous) by controlling the orientation behavior, it has a feature that can be reversibly adjusted the reflectance of the external light and transmittance of the transmitted light.

At this time, the mixed solution is made of a dichroic dye and a nematic liquid crystal, and is not cured by ultraviolet irradiation, so as to control the orientation behavior in the vertical or horizontal alignment by applying an electric field in accordance with the external light, the organic light emission that can be switched A display device can be provided.

FIG. 15 is a photograph illustrating an external reflection blocking mode and a transmission mode during reflection blocking through an organic light emitting display device in which the conventional reflection reducing film illustrated in FIG. 1 is laminated, and FIG. 16 is polarized light of the first embodiment of FIG. 3. It is a photograph observing the external reflection blocking mode and the transmission mode during the reflection blocking through the organic light emitting display device in which the device is stacked.

FIG. 17 is a transmissive mode result of an organic light emitting display device in which a polarizing element, which is switched from a horizontal orientation to a vertical orientation by application of an electric field, is stacked in the first embodiment of FIG. The transmission mode can be adjusted according to the condition of large or small.

FIG. 18 illustrates a front transmittance result of 100% of transmitted light of the organic light emitting display device of FIGS. 1, 3, and 5, and when the external reflection is large, the organic light emitting display device in which a conventional reflection reducing film is laminated; When the electric field is applied to the organic light emitting display device in which the polarizing element of the first embodiment of the present invention is stacked when the external reflectance is shown to be comparable, but the external reflection is small, a remarkable improvement can be seen as 70.901% of front transmittance. .

That is, the present invention applies an electric field to a polarizing element using a dichroic dye when the external reflection is small, and the dichroic dye is placed vertically on the substrate to transmit 70% or more of the light emitted from the organic light emitting display device, thereby lighting more than 50% of conventional light. Compared to the organic light emitting display device using the iodine type polarizing film that absorbs greatly improves the transmittance.

By controlling the transmittance, it is possible to selectively adjust the external reflected light and increase the efficiency of the front transmitted light, thereby increasing the life of the organic light emitting device. In more detail, outdoor visibility may be reduced by decreasing the intensity of external reflected light, and the lifetime of the device may be increased by increasing the light efficiency of the organic light emitting diode in a special situation.

In this case, the polarizing element of the first embodiment of the present invention was produced by containing a dichroic dye 0.8% by weight with respect to the liquid crystal mixed solution, the front transmittance was measured using a UV-Vis spectrometer and measured by the wavelength-specific transmittance measurement method It was.

That is, in the organic light emitting display device of the present invention, the result of the front reflectivity is similar to that of the related art, but by using the polarizer of the present invention, the front transmittance can be maximized by switching.

In addition, upon application of the electric field, the electric field strength, ie the applied voltage, will depend on the structure and material of the sample. For example, if the polarizer is 10 μm thick, the voltage which is converted from horizontal to vertical may be adjusted until about 90% of the maximum transmittance starts from about 1.5V to about 8V.

As described above, the polarizing device of the present invention can adjust the degree of reflected light and transmitted light by controlling the behavior of the dichroic dye and the liquid crystal through application of an electric field, and according to the application of the electric field, homeotropic and horizontal alignment (Homogeneous). By indicating the behavior of the orientation change of), the reflectance of the external light and the transmittance of the transmitted light can be reversibly adjusted.

Polarizing device for an organic light emitting display of the present invention serves as a conventional polarizing plate using a dichroic dye, while being oriented in the same direction as the liquid crystal of the electrical properties according to the electric field factor, especially when the external reflection is less polarized light using a dichroic dye Transmittance compared to organic light emitting display device using iodine type polarizing film that absorbs more than 50% of light by transmitting 70% or more of light emitted from organic light emitting display device by placing dichroic dye vertically on substrate by applying electric field to device This can be greatly improved.

In addition, by controlling the transmittance, it is possible to selectively control the external reflected light, increase the efficiency of the front transmitted light and increase the life of the organic light emitting device, increase the outdoor visibility by reducing the intensity of the external reflected light, and improve the light efficiency of the organic light emitting device in a special situation. Increase the lifetime of the device.

Although the present invention has been described in detail only with respect to the described embodiments, it will be apparent to those skilled in the art that various modifications and variations are possible within the technical scope of the present invention, and such modifications and modifications are within the scope of the appended claims.

10, 20, 30, 40: polarizer for organic light emitting display
11, 21, 31, 41: upper substrate 18, 28, 38, 48: lower substrate
12, 22, 32, 42: first electrode 17, 27, 37, 47: second electrode
13, 23, 33, 43: first horizontal alignment layer 16, 26, 36, 46: second horizontal alignment layer
14, 24, 34, 44: dichroic dye 15, 25, 35, 45: liquid crystal
19, 29, 39, 49: rubbing direction 100: antireflective film
110: l / 4 phase delay film 120: OLED
200: incident light
210: reflected light
300: OLED light

Claims (9)

A lower substrate and an upper substrate disposed to face each other,
A first electrode and a second electrode between the lower substrate and the upper substrate,
A first horizontal alignment layer and a second horizontal alignment layer between the first electrode and the second electrode,
Between the first horizontal alignment film and the second horizontal alignment film, a polarizing element filled with a liquid crystal mixed solution consisting of a dichroic dye and a liquid crystal,
A polarizing device for an organic light emitting display capable of changing the orientation of a dichroic dye and a liquid crystal by applying an electric field between the first electrode and the second electrode. The polarizing element for an organic light emitting display according to claim 1, wherein the liquid crystal is a nematic liquid crystal. The polarizing element for an organic light emitting display according to claim 1, wherein the dichroic dye is contained in an amount of 0.5 to 10% by weight based on the liquid crystal mixed solution. According to claim 1, wherein the polarizer is an alignment structure filled with a liquid crystal mixed solution consisting of a dichroic dye and a liquid crystal is any one of the orientation selected from the horizontal alignment (Homogeneous), the horizontal orientation or vertical orientation (Homeotropic) to the dual domain A polarizing element for an organic light emitting display, characterized in that the structure. The polarizer of claim 1, wherein the first electrode and the second electrode are patterned electrodes. The polarizing element of claim 1, wherein the first electrode and the second electrode are a transparent conductive material. The polarizing device of claim 1, wherein the lower substrate and the upper substrate are transparent substrates. On OLED
l / 4 phase delay film and
The organic light emitting display device of claim 1, wherein the organic light emitting display polarizing element is stacked and switched. The method of claim 8, wherein the polarization device for the organic light emitting display is a reversible reflectance of the external light and the transmittance of the transmitted light through the orientation conversion behavior of the homeotropic or horizontal alignment of the dichroic dye and the liquid crystal by applying an electric field Switchable organic light emitting display device, characterized in that adjusted to.

Images