KR102459596B1 - Organic Light Emitting Diode Display Device - Google Patents

Abstract

The present invention discloses an organic light emitting display device. The disclosed organic light emitting display device includes a first substrate divided into a plurality of sub-pixels, is disposed for each sub-pixel on the first substrate, and includes a first electrode including a reflective electrode and an organic light emitting layer emitting first light. and an organic light emitting device configured as a second electrode. In addition, in the organic light emitting display device of the present invention, a second substrate disposed to face the first substrate, a light recycling layer disposed on one surface of a second substrate in at least one sub-pixel among the plurality of sub-pixels, and the light recycling layer and a color conversion layer disposed in an area corresponding to the .

Description

Organic Light Emitting Diode Display Device

The present invention relates to an organic light emitting display device, and more particularly, to an organic light emitting display device capable of increasing light efficiency and color reproducibility.

As the information society develops, the demand for a display device for displaying an image is increasing in various forms, and in recent years, a liquid crystal display device (LCD), a plasma display panel device (PDP), Various flat panel display devices such as an organic light emitting diode display device (OLED) are being utilized.

Among such display devices, since the organic light emitting device uses a self-luminous device, a backlight used in a liquid crystal display device using a non-light emitting device is not required, so that it can be lightweight and thin. In addition, the organic light emitting display device has better viewing angle and contrast ratio than the liquid crystal display device, and is advantageous in terms of power consumption. In addition, the organic light emitting display device can be driven with a low DC voltage, has a fast response speed, is strong against external shocks because the internal components are solid, has a wide operating temperature range, and has advantages of low cost in terms of manufacturing cost.

Such an organic light emitting display device displays an image in the form of a top emission method or a bottom emission method according to the structure of an organic light emitting device including a first electrode, a second electrode, and an organic light emitting layer. The bottom light emitting method displays visible light generated from the organic light emitting layer toward the lower side of the substrate on which the TFT is formed, whereas the top light emitting method displays visible light generated from the organic light emitting layer toward the upper side of the substrate on which the TFT is formed.

Meanwhile, in an organic light emitting display device using an organic light emitting diode that emits white light, white light passes through a color filter and emits light of the same color as a color filter disposed on each sub-pixel. In this case, the organic light emitting layer of the organic light emitting device may implement white light using blue (Blue) and yellow-green (YG) light emitting layers. The organic light emitting diode display has an advantage in that it can be driven at a low voltage, and thus its utilization is increasing. In addition, since the organic light emitting device can be formed in a plurality of sub-pixels in the same process, there is an advantage in that the process is simplified.

Light emitted through the organic light emitting device may be white light having high spectral intensity in a wavelength region of 450 nm to 460 nm and a wavelength region of 540 nm to 560 nm. That is, since the light generated through the organic light emitting device has very low spectral intensity of wavelengths corresponding to deep green and deep red, there is a problem in that color gamut is reduced.

In addition, there is a problem in that light efficiency is lowered due to light lost during the process of converting light generated from the organic light emitting diode into a color emitted by each sub-pixel in a plurality of sub-pixels emitting different colors.

SUMMARY OF THE INVENTION The present invention is to solve the above problems, and an object of the present invention is to provide an organic light emitting display device capable of improving light efficiency and color gamut.

The organic light emitting display device of the present invention for solving the problems of the prior art as described above includes a first substrate divided into a plurality of sub-pixels, a first electrode disposed for each sub-pixel on the first substrate and including a reflective electrode; An organic light emitting device comprising an organic light emitting layer emitting first light and a second electrode, a second substrate disposed to face the first substrate, and at least one sub pixel among the plurality of sub pixels on one surface of the second substrate and a light recycling layer disposed thereon and a color conversion layer disposed in an area corresponding to the light recycling layer.

The light recycling layer may be alternately disposed with a high refractive index layer and a low refractive index layer. In this case, the thickness of the high refractive index layer may be thinner than the thickness of the low refractive index layer.

The color conversion layer may be disposed on the light recycling layer or disposed on one surface of the second substrate. In addition, the color conversion layer may be disposed between the first electrode and the organic light emitting layer.

Meanwhile, the first light has a maximum spectral intensity at a wavelength of 450 nm to 460 nm. In addition, the first color conversion layer disposed in the first sub-pixel included in the plurality of sub-pixels may convert the first light into the second light having the maximum spectral intensity at a wavelength of 620 nm to 640 nm. In addition, the second color conversion layer disposed in the second sub-pixel included in the plurality of sub-pixels may convert the first light into third light having a maximum spectral intensity at a wavelength of 540 nm to 560 nm.

In the organic light emitting display device according to the present invention, a light recycling layer disposed on one surface of the second substrate is disposed in at least one sub-pixel among a plurality of sub-pixels, so that light of a wavelength other than the light emitted from each sub-pixel is applied. By converting the wavelength of the light emitted from the sub-pixel, there is an effect of improving luminance and light efficiency.

In addition, the organic light emitting display device according to the present invention has the effect of increasing the spectral intensity of light emitted from each sub-pixel and thus improving the color gamut by disposing the color conversion layer in the region corresponding to the light recycling layer. .

1 is a schematic system configuration diagram of a display device according to example embodiments.
2 is a diagram illustrating an optical path in an organic light emitting diode display according to an exemplary embodiment of the present invention.
3A and 3B are diagrams illustrating a light path by a light recycling layer according to an embodiment of the present invention.
4 is a plan view illustrating an organic light emitting display device according to a first embodiment of the present invention.
5 is a cross-sectional view illustrating one pixel of the organic light emitting diode display according to the first exemplary embodiment of the present invention.
6 is a view showing another embodiment of the first electrode of the organic light emitting device of the present invention.
7 is a diagram illustrating an optical path in an organic light emitting diode display according to another exemplary embodiment of the present invention.
8 is a plan view illustrating an organic light emitting display device according to a second exemplary embodiment of the present invention.
9 is a cross-sectional view illustrating one pixel of an organic light emitting diode display according to a second exemplary embodiment of the present invention.
10 is a view showing an arrangement of a color conversion layer according to another embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The embodiments introduced below are provided as examples so that the spirit of the present invention can be sufficiently conveyed to those skilled in the art. Accordingly, the present invention is not limited to the embodiments described below and may be embodied in other shapes. And in the drawings, the size and thickness of the device may be exaggerated for convenience. Like reference numerals refer to like elements throughout.

Advantages and features of the present invention and methods of achieving them will become apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in a variety of different shapes, and only these embodiments allow the disclosure of the present invention to be complete, and common knowledge in the art to which the present invention pertains It is provided to fully inform those who have the scope of the invention, and the present invention is only defined by the scope of the claims. Like reference numerals refer to like elements throughout. The sizes and relative sizes of layers and regions in the drawings may be exaggerated for clarity of description.

Reference to an element or layer to another element or “on” or “on” includes not only directly on the other element or layer, but also with other layers or other elements interposed therebetween. do. On the other hand, reference to an element "directly on" or "directly on" indicates that there are no intervening elements or layers.

The spatially relative terms "below, beneath", "lower", "above", "upper", etc. are one element or component as shown in the drawings. and can be used to easily describe the correlation with other devices or components. Spatially relative terms should be understood as terms including different directions of the device during use or operation in addition to the directions shown in the drawings. For example, when an element shown in the figures is turned over, an element described as "beneath" or "beneath" another element may be placed "above" the other element. Accordingly, the exemplary term “below” may include both directions below and above.

In addition, in describing the components of the present invention, terms such as first, second, A, B, (a), (b), etc. may be used. These terms are only for distinguishing the elements from other elements, and the essence, order, order, or number of the elements are not limited by the terms.

1 is a schematic system configuration diagram of a display device according to example embodiments. Referring to FIG. 1 , in the display device 1000 according to the present exemplary embodiments, a plurality of data lines DL1 to DLm and a plurality of gate lines GL1 to GLn are disposed, and a plurality of sub-pixels are provided. The display panel 1100, the data driver 1200 driving the plurality of data lines DL1 to DLm, the gate driver 1300 driving the plurality of gate lines GL1 to GLn, the data driver 1200, and and a timing controller 1400 for controlling the gate driver 1300 .

The data driver 1200 drives a plurality of data lines by supplying data voltages to the plurality of data lines. In addition, the gate driver 1300 sequentially drives the plurality of gate lines by sequentially supplying scan signals to the plurality of gate lines.

Also, the timing controller 1400 controls the data driver 1200 and the gate driver 1300 by supplying control signals to the data driver 1200 and the gate driver 1300 . The timing controller 1400 starts scanning according to the timing implemented in each frame, converts the input image data input from the outside to match the data signal format used by the data driver 1200, and outputs the converted image data. , control the data drive at an appropriate time according to the scan.

The gate driver 1300 sequentially drives the plurality of gate lines by sequentially supplying a scan signal of an on voltage or an off voltage to the plurality of gate lines under the control of the timing controller 1400 . . In addition, the gate driver 1300 may be positioned on only one side of the display panel 1100 as shown in FIG. 1 or on both sides in some cases, depending on a driving method or a display panel design method.

Also, the gate driver 1300 may include one or more gate driver integrated circuits. Each gate driver integrated circuit is connected to a bonding pad of the display panel 1100 by a tape automated bonding (TAB) method or a chip-on-glass (COG) method, or a gate in panel (GIP) type. may be implemented and disposed directly on the display panel 1100 , or may be integrated and disposed on the display panel 1100 in some cases.

In addition, each gate driver integrated circuit may be implemented in a Chip On Film (COF) method. In this case, the gate driving chip corresponding to each gate driver integrated circuit may be mounted on a flexible film, and one end of the flexible film may be bonded to the display panel 1100 .

When a specific gate line is opened, the data driver 1200 converts the image data received from the timing controller 1400 into analog data voltage and supplies it to the plurality of data lines, thereby driving the plurality of data lines. In addition, the data driver 1200 may drive a plurality of data lines including at least one source driver integrated circuit.

Each source driver integrated circuit is connected to a bonding pad of the display panel 1100 by a tape automated bonding (TAB) method or a chip-on-glass (COG) method, or directly to the display panel 1100 . It may be disposed or, in some cases, may be integrated and disposed on the display panel 1100 .

In addition, each source driver integrated circuit may be implemented in a chip on film (COF) method. In this case, the source driving chip corresponding to each source driver integrated circuit is mounted on a flexible film, one end of the flexible film is bonded to at least one source printed circuit board (Source Printed Circuit Board), and the other end is the display panel ( 1100) is bonded.

The source printed circuit board is connected to the control printed circuit board through a connection medium such as a flexible flat cable (FFC) or a flexible printed circuit (FPC). A timing controller 1400 is disposed on the control printed circuit board.

In addition, a power controller (not shown) that supplies voltage or current to the display panel 1100 , the data driver 1200 , and the gate driver 1300 , or controls the voltage or current to be supplied, may be further disposed on the control printed circuit board have. The above-mentioned source printed circuit board and control printed circuit board may be a single printed circuit board.

Meanwhile, a pixel of the present invention includes one or more subpixels. The sub-pixel refers to a unit in which a specific color filter is formed or a color filter is not formed and the organic light emitting device can emit a special color. The colors defined in the sub-pixel may include red (R), green (G), blue (B), and optionally white (W), but the present invention is not limited thereto. Since each sub-pixel includes a separate thin film transistor and an electrode connected thereto, the sub-pixels constituting the pixel may also be referred to as one pixel region hereinafter.

In addition, an electrode connected to the thin film transistor for controlling light emission of each sub-pixel area of the display panel is referred to as a first electrode, and an electrode disposed on the front surface of the display panel or disposed to include two or more pixel areas is referred to as a second electrode. . When the first electrode is an anode electrode, the second electrode is a cathode electrode, and vice versa. Hereinafter, an anode electrode as an embodiment of the first electrode and a cathode electrode as an embodiment of the second electrode will be mainly described, but the present invention is not limited thereto.

Next, a light path in a schematic organic light emitting display device according to an embodiment of the present invention will be described as follows. 2 is a diagram illustrating an optical path in an organic light emitting diode display according to an exemplary embodiment of the present invention.

Referring to FIG. 2 , an organic light emitting display device according to an embodiment of the present invention includes a reflective electrode 111 , an organic light emitting layer 140 , a counter electrode 150 , a color conversion layer 210 , and a light recycling layer 250 . includes In this case, the reflective electrode 111 , the organic light emitting layer 140 , the counter electrode 150 , the color conversion layer 210 , and the light recycling layer 250 may be sequentially stacked in a vertical direction, respectively. In addition, although FIG. 2 shows a configuration in which the reflective electrode 111 is a single layer, in the organic light emitting display device according to an embodiment of the present invention, the reflective electrode 111 may be formed in multiple layers. For example, the reflective electrode 111 may include a reflective layer and a transparent conductive layer.

A first light may be emitted from the organic light emitting layer 140 . The first light λ1 may be light having a maximum spectral intensity at a wavelength of 450 nm to 460 nm. A portion of the first light λ1 emitted from the organic light emitting layer 140 may be emitted toward the counter electrode 150 , and the remaining portion may be emitted toward the reflective electrode 111 .

The first light λ1 emitted in the direction of the counter electrode 150 passes through the counter electrode 150 and passes through the color conversion layer 210 . At this time, the color conversion layer 210 may convert the first light (λ1) into the second light (λ2) or the third light (λ3).

The second light λ2 is light having a maximum spectral intensity at a wavelength of 620 nm to 640 nm, and the third light λ3 is light having a maximum spectral intensity at a wavelength of 540 nm to 560 nm. The light converted into the second light (λ2) or the third light (λ13) through the color conversion layer 210 may pass through the light recycling layer 250 to be emitted to the outside.

On the other hand, the first light (λ1) that is not converted to the second light (λ2) or the third light (λ3) through the color conversion layer 210 is reflected by the light recycling layer 250 to the reflective electrode ( 111), the direction is changed. That is, the light recycling layer 250 transmits light having a maximum spectral intensity higher than the maximum spectral intensity of the first light λ1, and has a maximum spectrum lower than the first light λ1 and the first light λ1. Light with intensity can be reflected.

The light recycling layer 250 may be formed of two or more layers as shown in FIG. 2 . In this case, in the light recycling layer 250 , a high refractive index layer 250a and a low refractive index layer 250b may be alternately disposed. Here, a high refractive index layer 250a may be disposed on the lowermost layer and the uppermost layer of the light recycling layer 250 . Since the light recycling layer 250 has a structure in which the high refractive index layer 250a and the low refractive index layer 250b are alternately disposed, it is possible to transmit light of a long wavelength and reflect light of a short wavelength.

The light path by the light recycling layer 250 will be described in detail with reference to FIGS. 3A and 3B . 3A and 3B are diagrams illustrating a light path by a light recycling layer according to an embodiment of the present invention.

Referring to FIGS. 3A and 3B , the light recycling layer 250 may be configured as a multi-layer by alternately disposing a high refractive index layer 250a and a low refractive index layer 250b. For example, the light recycling layer 250 may include at least one high refractive index layer 250a and one low refractive index layer 250b.

The high refractive index layer 250a may be made of titanium oxide (TiO2), and the low refractive index layer 250b may be made of silicon oxide (SiO2), but is not limited thereto, and the high refractive index layer 250a and the low refractive index layer 250a It is sufficient if the layer 250b is made of a material having a refractive index difference from each other.

On the other hand, when the second light (λ2) or the third light (λ3) is incident on the light recycling layer 250 having the above-described configuration as shown in FIG. 3A, the second light (λ2) or the third light (λ3) passes through the high refractive index layer 250a to reach the interface between the high refractive index layer 250a and the low refractive index layer 250b. In addition, the light incident at an angle of incidence of the second light λ2 or the third light λ3 at the interface between the high refractive index layer 250a and the low refractive index layer 250b below the total reflection critical angle is the low refractive index layer 250b. are entered

When the incident angle of the second light λ2 or the third light λ3 is greater than the total reflection critical angle at the interface between the high refractive index layer 250a and the low refractive index layer 250b, the high refractive index layer 250a and the low refractive index layer 250a Although it may be totally reflected at the interface of the layer 250b, it is reflected by a reflective electrode disposed to overlap the lower portion of the light recycling layer 250 so that the second light (λ2) or the third light (λ3) is again transmitted to the light recycling layer ( 250), and an incident angle at the interface between the high refractive index layer 250a and the low refractive index layer 250b may be less than or equal to the total reflection critical angle.

Then, the second light λ2 or the third light λ3 incident on the low refractive index layer 250b reaches the interface with the other high refractive index layer 250a disposed on the low refractive index layer 250b. , is refracted due to a difference in refractive index between the high refractive index layer 250a and the low refractive index layer 250b at the interface between the high refractive index layer 250a and the low refractive index layer 250b and is incident on the high refractive index layer 250a.

The second light λ2 or the third light λ3 may be emitted to the outside of the light recycling layer 250 through the above-described process.

On the other hand, as shown in FIG. 3B , the light incident at the interface between the high refractive index layer 250a and the low refractive index layer 250b at an incident angle of the first light λ1 is greater than or equal to the total reflection critical angle is the high refractive index layer 250a. It is totally reflected at the interface of the low refractive index layer 250b and is switched back to the high refractive index layer 250a. In addition, the light having the incident angle of the first light λ1 being less than or equal to the total reflection critical angle passes through the low refractive index layer 250b and is totally reflected at the interface with the other high refractive index layer 250a.

That is, the first light λ1 is blocked, that is, reflected by the light recycling layer 250 , and the second light λ2 or the third light λ3 may be emitted to the outside of the light recycling layer 250 . .

Meanwhile, the thickness of the high refractive index layer 250a of the light recycling layer 250 may be thinner than the thickness of the low refractive index layer 250b. For example, the high refractive index layer 250a may have a thickness of 20 nm to 60 nm, and the low refractive index layer 250b may have a thickness of 65 nm to 90 nm.

As described above, since the high-refractive-index layer 250a is made thinner than the low-refractive-index layer 250b, the first light λ1, which is light of a lower wavelength, is reflected, and the second light, which is light of a higher wavelength than the first light λ1 ( λ2) or the third light (λ3) may be transmitted. That is, the light recycling layer 250 according to an embodiment may reflect or transmit light of a specific wavelength by adjusting the thicknesses of the high refractive index layer 250a and the low refractive index layer 250b.

Specifically, by adjusting the thickness of the high refractive index layer 250a and the low refractive index layer 250b, the thickness of the high refractive index layer has a thickness of 1/4 of the band center wavelength, and the thickness of the low refractive index layer is a band It may have a thickness of 1/4 compared to the center wavelength, and through this, circular polarization and linear polarization effects can be obtained through the light recycling layer 250, whereby the light recycling layer 250 blocks light according to each wavelength. or reflect it.

Meanwhile, in FIG. 2 , the first light λ1 reflected by the light recycling layer 250 passes through the color conversion layer 210 , the counter electrode 150 , and the organic light emitting layer 140 in order to the reflective electrode 111 . reach In this case, the refractive indices of the color conversion layer 210 , the counter electrode 150 , and the organic light emitting layer 140 may be similar to each other. Accordingly, the first light λ1 reaches the reflective electrode 111 without being totally reflected at the interface between the color conversion layer 210 and the counter electrode 150 and at the interface between the counter electrode 150 and the organic light emitting layer 140 . can do.

The first light λ1 reaching the reflective electrode 111 is reflected by the reflective electrode 111 and reaches the color conversion layer 210 through the organic light emitting layer 140 and the counter electrode 150 again. Among the first light λ1 emitted from the organic light emitting layer 140 , the first light λ1 emitted toward the reflective electrode 111 also passes through the organic light emitting layer 140 and the counter electrode 150 through the color conversion layer. (210) is reached.

The first light λ1 reaching the color conversion layer 210 is converted into the second light λ2 or the third light λ3 by the color conversion layer 210, and the second light λ2 or The third light λ3 may be emitted to the outside of the light recycling layer 250 through the light recycling layer 250 .

The organic light emitting display device of the present invention to which the components of the organic light emitting display device according to the above-described embodiment are applied will be reviewed as follows. 4 is a plan view illustrating an organic light emitting display device according to a first embodiment of the present invention.

Referring to FIG. 4 , in the organic light emitting diode display according to the first embodiment, a first substrate 100 as a lower substrate and a second substrate 200 as an upper substrate are disposed to face each other. The first substrate 100 and the second substrate 200 are divided into a plurality of sub-pixels. Meanwhile, in the organic light emitting diode display according to the first embodiment of the present invention, two to four sub-pixels may be included in one pixel. However, in the following description for convenience of description, three sub-pixels are included in one pixel. The included configuration will be mainly described.

In detail, one pixel P includes a first sub-pixel SP1 , a second sub-pixel SP2 , and a third sub-pixel SP3 . Here, the first sub-pixel SP1 is a red (R) sub-pixel, the second sub-pixel SP2 is a green (G) sub-pixel, and the third sub-pixel SP3 is a blue (B) sub-pixel. can

A driving transistor Tr for driving an organic light emitting diode is disposed on the first substrate 100 of each sub-pixel. In addition, the first electrode 120 of the organic light emitting device connected to the driving transistor Tr is disposed on the first substrate 100 . In this case, a bank pattern 130 for dividing a light-emitting area and a non-emission area is disposed on a portion of the upper surface of the first electrode 120 .

The second substrate 200 is disposed to face the first substrate 100 having such a configuration. A first color conversion layer 210 and a second color conversion layer 220 are respectively disposed on the first sub-pixel and the second sub-pixel of the second substrate 200 , and a third color conversion layer is disposed on the third sub-pixel, respectively. 230 may be disposed. Here, the third color conversion layer 230 may be a color filter layer. In addition, a light recycling layer 250 may be disposed between the second substrate 200 and the first color conversion layer 210 in the first sub-pixel.

In addition, the organic light emitting display device according to the first embodiment is disposed to overlap between the first color conversion layer 210 and the second color conversion layer 220, and the second color conversion layer 220 and the third color conversion layer 220 The light blocking layer 240 is disposed to overlap between the color conversion layers 230 and may include a light blocking layer 240 disposed to overlap between the third color conversion layer 230 and the first color conversion layer 210 . Here, the light blocking layer 240 may be made of an opaque organic material, but is not limited thereto.

A detailed review of such a configuration with reference to FIG. 5 is as follows. 5 is a cross-sectional view illustrating one pixel of the organic light emitting diode display according to the first exemplary embodiment of the present invention. Referring to FIG. 5 , in the organic light emitting diode display according to the first exemplary embodiment, one pixel P includes a first sub-pixel SP1 , a second sub-pixel SP3 , and a third sub-pixel SP3 . .

In addition, the organic light emitting device EL is disposed on the first substrate 100 in each of the sub-pixels SP1 , SP2 , and SP3 . The organic light emitting device EL may include a first electrode 120 , an organic light emitting layer 140 , and a second electrode 150 . A reflective layer 110 may be disposed under the first electrode 120 .

Meanwhile, the configuration of the first electrode 120 of the organic light emitting device EL is not limited to the configuration illustrated in FIG. 5 , and may be formed as illustrated in FIG. 6 . 6 is a view showing another embodiment of the first electrode of the organic light emitting device of the present invention.

Referring to FIG. 6 , the first electrode 121 of the organic light emitting device EL may be formed of a triple layer. In detail, the first layer 122 of the first electrode 121 is disposed on the substrate 100 , and the second layer 123 of the first electrode 121 is disposed on the first layer 122 , , a third layer 124 of the first electrode 121 may be disposed on the second layer 123 .

In this case, at least one of the first to third layers 122 , 123 , and 124 may be formed of a reflective material. For example, the second layer 123 may be formed of a reflective material. In addition, the first layer 122 and the third layer 124 may be formed of a transparent conductive material.

In FIG. 5 , a bank pattern 130 defining an emission area EA of each of the sub-pixels SP1 , SP2 , and SP3 may be disposed on a portion of the upper surface of the first electrode 120 . The organic light emitting device EL disposed in each of the sub-pixels SP1, SP2, and SP3 may emit the first light. The first light may be light having a maximum spectral intensity at a wavelength of 450 nm to 460 nm. Also, although not shown in the drawings, the organic light emitting layer 140 according to the first embodiment of the present invention may be configured in any one of 1 stack to 3 stacks.

An encapsulation layer 160 for protecting the organic light emitting device EL is disposed on the organic light emitting device EL. In addition, the second substrate 200 is disposed to face the first substrate 100 . A filler 170 may be disposed between the first substrate 100 and the second substrate 200 .

A light recycling layer 250 , a color conversion layer and a light blocking layer 240 are disposed on one surface of the second substrate 200 . Here, the light recycling layer 250 may be disposed in the first sub-pixel SP1 and the second sub-pixel SP2. In detail, in the first sub-pixel SP1 , a light recycling layer 250 is disposed on one surface of the second substrate 200 , and a first color conversion layer 210 is disposed on the light recycling layer 250 . do. In addition, in the second sub-pixel SP2 , a light recycling layer 250 is disposed on one surface of the second substrate 200 , and a second color conversion layer 220 is disposed on the light recycling layer 250 .

The light recycling layer 250 disposed on the first sub-pixel SP1 and the second sub-pixel SP2 may have the same thickness and thickness. Since the light recycling layer 250 is made under the same conditions in the first sub-pixel SP1 and the second sub-pixel SP2, the light is applied to the first sub-pixel SP1 and the second sub-pixel SP2 in the same process. A recycling layer 250 may be formed.

A third color conversion layer 230 is disposed on one surface of the second substrate 200 in the third sub-pixel SP3 . In addition, the light blocking layer 240 may be disposed in a region corresponding to the boundary of the different color conversion layers 210 , 220 , 230 .

5 discloses a configuration in which the light blocking layer 240 is disposed on the boundary of the different color conversion layers 210 , 220 , 230 , but the organic light emitting display device according to the first embodiment of the present invention is not limited thereto. The light blocking layer 240 is a light blocking layer 240 is disposed on the second substrate 200, and a light recycling layer 250 on the second substrate 200 on which the light blocking layer 240 is disposed. and first to third color conversion layers 210 , 220 , and 230 may be disposed.

Meanwhile, in the first sub-pixel SP1 and the second sub-pixel SP2 , the first light emitted from the organic light emitting diode EL may exhibit the behavior characteristics described above with reference to FIGS. 2 and 3 .

For example, in the first sub-pixel SP1 , a portion of the first light emitted from the organic light emitting layer 140 may be emitted toward the second electrode 150 , and the remaining portion may be emitted toward the reflective layer 110 . . The first light emitted in the direction of the second electrode 150 passes through the first color conversion layer 210 through the second electrode 150 .

In this case, the first color conversion layer 210 may convert the first light into the second light. The second light is light having a maximum spectral intensity at a wavelength of 620 nm to 640 nm. The light converted into the second light through the first color conversion layer 210 may pass through the light recycling layer 250 to be emitted to the outside.

On the other hand, the first light that is not converted to the second light through the first color conversion layer 210 is reflected by the light recycling layer 250 and the direction is converted to the reflective layer 110 . The first light reflected by the light recycling layer 250 is the first color conversion layer 210 , the filler 170 , the encapsulation layer 160 , the second electrode 150 , the organic light emitting layer 140 , and the first electrode. The reflective layer 110 is reached through 120 in turn.

The first light reaching the reflective layer 110 is reflected by the reflective layer 110 , and again the first electrode 120 , the organic light emitting layer 140 , the second electrode 150 , the encapsulation layer 160 , and the filler 170 . ) to reach the first color conversion layer 210 . In addition, among the first lights emitted from the organic light emitting layer 140 , the first light emitted in the direction of the reflective layer 110 is also the first electrode 120 , the organic light emitting layer 140 , the second electrode 150 , and the encapsulation layer ( 160 ) and the filler 170 to reach the first color conversion layer 210 .

The first light reaching the color conversion layer 210 is converted to the second light λ2 by the first color conversion layer 210, and the second light λ2 is the light recycling layer 250 Through this, light may be emitted to the outside of the second substrate 200 .

In this way, the light recycling layer 250 and the first color conversion layer 210 are disposed to correspond to each other in the first sub-pixel SP1, so that the maximum spectral intensity at a wavelength of 450 nm to 460 nm from the organic light emitting layer (EL) is obtained. Even though the first light having the first light is emitted, it is converted into the second light having the maximum spectral intensity at a wavelength of 620 nm to 640 nm by the first color conversion layer 210, and is changed to the second light by the light recycling layer 250 The failed first light may be finally converted into the second light. Accordingly, the luminance of the first sub-pixel SP1 is improved, and the amount of unnecessary first light is reduced, so that the color gamut can be increased.

In addition, since the second color conversion layer 220 is disposed in the second sub-pixel SP2, the first light having the maximum spectral intensity at a wavelength of 450 nm to 460 nm is emitted from the organic light emitting layer (EL), It may be converted into third light having a maximum spectral intensity at a wavelength of 540 nm to 560 nm by the second color conversion layer 220 . At this time, the unconverted second light is reflected by the light recycling layer 250 until it is converted into the third light and is redirected to the reflective layer 110 , and the second light is reflected by the reflective layer 110 , Upon reaching the second color conversion layer 220 , it may be converted into third light and emitted to the outside.

In addition, by disposing the third color conversion layer 230 in the third sub-pixel SP3, the color gamut of the first light having the maximum spectral intensity at a wavelength of 450 nm to 460 nm from the organic light emitting layer EL may be increased. . In detail, the third color conversion layer 230 may further increase the spectral intensity at a wavelength of 450 nm to 460 nm than the first light.

Accordingly, the color gamut of the first light passing through the third color conversion layer 230 may be further improved. On the other hand, the thickness of the third color conversion layer 230 and the light recycling layer 250 may be the same or the thickness of the light recycling layer 250 may be made thinner than the thickness of the third color conversion layer 230 , which may be a color filter layer. have. That is, in the organic light emitting display device according to the first embodiment of the present invention, the thickness of the light recycling layer 250 can be variously changed under conditions for obtaining desired optical characteristics.

In the organic light emitting display device according to the first embodiment of the present invention, the organic light emitting layer 140 emits first light to the first sub-pixel SP1, the second sub-pixel SP2, and the third sub-pixel SP3. Even if , is formed by the same process, light having a different wavelength may be emitted from each sub-pixel. Therefore, there is an effect that the process of forming the organic light emitting device (EL) can be simplified. In addition, since the first light has a maximum spectral intensity at a wavelength of 450 nm to 460 nm, the second light or the second light having higher energy than the first light in the first sub-pixel SP1 and the second sub-pixel SP2 3 Can be easily converted to light.

The organic light emitting diode display according to the first embodiment of the present invention has the structure as described above, so that the first light emitted from the organic light emitting device EL is converted into the second light in the first sub-pixel SP1 and , may be converted into the third light in the second sub-pixel SP2 . Also, in the third sub-pixel SP3 , the color reproducibility may be increased while the first light emitted from the organic light emitting device EL passes through the third color conversion layer 230 .

In addition, in the organic light emitting display device according to the first exemplary embodiment of the present invention, the unnecessary first light is converted into the second light and the third light in the first sub-pixel SP1 and the second sub-pixel SP2, respectively. There is an effect of improving luminous efficiency in the first sub-pixel SP1 and the second sub-pixel SP2.

Next, referring to FIG. 7 , an optical path in the organic light emitting diode display according to another embodiment of the present invention will be described as follows. 7 is a diagram illustrating an optical path in an organic light emitting diode display according to another exemplary embodiment of the present invention.

Referring to FIG. 7 , an organic light emitting display device according to an embodiment of the present invention includes a reflective electrode 111 , a color conversion layer 310 , an organic light emitting layer 140 , a counter electrode 150 , and a light recycling layer 350 . This includes a sequentially stacked configuration. Here, the organic light emitting layer 140 emits the first light. The behavior of the first light can be roughly described in three ways.

First, the first light λ1 is emitted from the organic light emitting layer 140 , and some of the first light λ1 passes through the color conversion layer 310 to reach the reflective electrode 111 . In this case, the first light λ1 is converted into the second light λ2 or the third light λ3 by the color conversion layer 310 . The second light λ2 or the third light λ3 is reflected by the reflective electrode 111 and passes through the color conversion layer 310 again to the organic light emitting layer 140 , the counter electrode 150 , and the light recycling layer 350 . ) is transmitted sequentially and emitted to the outside.

Second, in the first behavior, the first light (λ1) that is not converted into the second light (λ2) or the third light (λ3) by the color conversion layer 310 is reflected by the light recycling layer (350) and reaches the color conversion layer 310 again through the counter electrode 150 and the organic light emitting layer 140 . At this time, the first light (λ1) is converted into the second light (λ2) or the third light (λ3) by the color conversion layer 310, is reflected back by the reflective electrode 111, the light recycling layer ( 350) and is emitted to the outside. Here, the above-described behavior may be repeated until the first light λ1 is converted into the second light λ2 or the third light λ3.

Third, a portion of the first light λ1 emitted from the organic light emitting layer 140 is emitted toward the counter electrode 150 . The first light λ1 reaches the light recycling layer 350 through the counter electrode 150, but is reflected by the light recycling layer 350 and passes through the counter electrode 150 and the organic light emitting layer 140 again. to pass through the color conversion layer 310 . At this time, the first light λ1 is converted into the second light λ2 or the third light λ3.

The second light λ2 or the third light λ3 is reflected by the reflective electrode 111 and passes through the color conversion layer 310 again to the organic light emitting layer 140 , the counter electrode 150 , and the light recycling layer 350 . ) is transmitted sequentially and emitted to the outside. Here, when the first light is not converted into the second light λ2 or the third light λ3 by the color conversion layer 310 , the first light λ1 is reflected by the light recycling layer 350 . Thus, it may reach the color conversion layer 310 again and be converted into the second light (λ2) or the third light (λ3).

That is, the light recycling layer 350 may transmit light having a wavelength greater than that of the first light λ1 and reflect light having a wavelength similar to or lower than that of the first light λ1 .

The organic light emitting display device of the present invention to which the components of the organic light emitting display device according to the above-described embodiment are applied will be reviewed as follows. 8 is a plan view illustrating an organic light emitting display device according to a second exemplary embodiment of the present invention.

The organic light emitting diode display according to the second exemplary embodiment of the present invention may include the same components as those of the above-described exemplary embodiment. A description that overlaps with the above-described embodiments may be omitted. Also, the same components have the same reference numerals.

Referring to FIG. 8 , an organic light emitting device is disposed in each sub-pixel SP1 , SP2 , and SP3 of the first substrate 100 , and the organic light emitting device is disposed in the first sub-pixel SP1 and the second sub-pixel SP2 . A first color conversion layer and a second color conversion layer may be respectively disposed under the first electrode 220 of the light emitting device. In addition, the light recycling layer 350 may be disposed on the first sub-pixel SP1 of the second substrate 200 .

A detailed review of such a configuration with reference to FIG. 9 is as follows. 9 is a cross-sectional view illustrating one pixel of an organic light emitting diode display according to a second exemplary embodiment of the present invention. Referring to FIG. 9 , in the organic light emitting diode display according to the second exemplary embodiment of the present invention, one pixel P includes a first sub-pixel SP1, a second sub-pixel SP3, and a third sub-pixel SP3. includes

In this case, in the first sub-pixel SP1 and the second sub-pixel SP2 on the first substrate 100 , the first color is provided between the first electrode 220 of the organic light emitting diode EL and the reflective layer 110 , respectively. A conversion layer 310 and a second color conversion layer 320 are disposed. Meanwhile, although FIG. 10 illustrates a configuration in which the first color conversion layer 310 and the second color conversion layer 320 are disposed between the first electrode 220 and the reflective layer 110, the present invention is limited to this structure. it's not going to be

Referring to FIG. 10, it is as follows. 10 is a view showing an arrangement of a color conversion layer according to another embodiment of the present invention. In FIG. 9 , both ends of the first and second color conversion layers 310 and 320 and the reflective layer 110 are arranged to match, and the first electrode 220 surrounds both sides, but FIG. 10 . In , the first color conversion layer 311 and the second color conversion layer 321 are disposed only on a portion of the upper surface of the reflective layer 110 , and the first electrode 221 is formed with the first and second color conversion layers 311 and 321 . ) is disposed to surround both sides of the reflective layer 110 and may be in contact with a portion of the upper surface of the reflective layer 110 .

Here, when the structure shown in FIG. 9 is formed, the first light emitted from the organic light emitting layer 140 is reflected by the reflective layer 110 and passes through the color conversion layer to be easily converted into the second light or the third light. have.

In detail, when the first and second color conversion layers 310 and 320 coincide with both ends of the reflective layer 110 , all of the first light reflected by the reflective layer 110 is converted to the first color. By passing through the layer 310 or the second color conversion layer 320 , the second light or the third light may be easily converted.

In addition, when the structure shown in FIG. 10 is formed, the reflective layer 110 in contact with the driving transistor and the first electrode 111 may be easily contacted.

In FIG. 9 , a light recycling layer 350 and a light blocking layer 340 are disposed on one surface of the second substrate 200 . In detail, in the first sub-pixel SP1 and the second sub-pixel SP2, a light recycling layer 350 is disposed on one surface of the second substrate 200, and in the third sub-pixel SP3, a light recycling layer ( 350) may not be placed.

In addition, the light blocking layer 340 may be disposed in a region corresponding to the boundary of each sub-pixel. Meanwhile, a third color conversion layer 230 may be disposed on one surface of the second substrate 200 in the third sub-pixel SP3 . In this case, the third color conversion layer 230 may be a color filter layer.

As described above, in the organic light emitting display device according to the second embodiment of the present invention, the light recycling layer 350 and the first color conversion layer 310 are disposed to correspond to each other in the first sub-pixel SP1, and the second sub-pixel By disposing the light recycling layer 350 and the second color conversion layer 320 to correspond to each other in (SP2), the first light having the maximum spectral intensity at a wavelength of 450 nm to 460 nm is emitted from the organic light emitting layer (EL). The first light that is converted into the second light or the third light by the first color conversion layer 310 and is not converted into the second light or the third light by the light recycling layer 350 is finally the second light or the second light. 3 Can be converted into light. Accordingly, the luminance of the first sub-pixel SP1 and the second sub-pixel SP2 is improved, and the amount of unnecessary first light is reduced, thereby increasing the color gamut.

As described above, in the organic light emitting display device according to the embodiments of the present invention, although each sub-pixel includes an organic light emitting layer emitting the same color, light efficiency is improved and color through the color conversion layer and the light recycling layer. It has the effect of increasing the reproducibility.

Features, structures, effects, etc. described in the above embodiments are included in at least one embodiment of the present invention, and are not necessarily limited to one embodiment. Furthermore, features, structures, effects, etc. illustrated in each embodiment can be combined or modified for other embodiments by those of ordinary skill in the art to which the embodiments belong. Accordingly, the contents related to such combinations and modifications should be interpreted as being included in the scope of the present invention.

In addition, although the embodiments have been described above, these are merely examples and do not limit the present invention, and those of ordinary skill in the art to which the present invention pertains are exemplified above in a range that does not depart from the essential characteristics of the present embodiment. It can be seen that various modifications and applications that have not been made are possible. For example, each component specifically shown in the embodiments may be implemented by modification.

111: reflective electrode
140: organic light emitting layer
150: counter electrode
210: color conversion layer
250: light recycling layer

Claims (19)

a first substrate divided into a plurality of sub-pixels;
a reflective layer positioned on the first substrate;
an organic light emitting device including a first electrode disposed for each sub-pixel on the first substrate, an organic light emitting layer disposed on the first electrode and emitting a first light, and a second electrode;
a second substrate disposed to face the first substrate; and
a color conversion layer positioned on the first substrate;
a color filter layer disposed on one surface of the second substrate in at least one sub-pixel among the plurality of sub-pixels and a light recycling layer disposed on one surface of the second substrate in at least one sub-pixel except for the sub-pixel on which the color filter layer is disposed; includes,
The color conversion layer is positioned between the first electrode and the reflective layer.
The method of claim 1,
The light recycling layer is alternately arranged with a high refractive index layer and a low refractive index layer,
An organic light emitting display device in which a high refractive index layer is disposed on the lowermost layer and the uppermost layer of the light recycling layer.
3. The method of claim 2,
The thickness of the high refractive index layer is thinner than that of the low refractive index layer.
3. The method of claim 2,
The thickness of the high refractive index layer has a thickness of 1/4 of the band center wavelength, and the low refractive index layer has a thickness of 1/4 of the band center wavelength.
delete The method of claim 1,
The thickness of the color filter layer and the light recycling layer is the same or the thickness of the light recycling layer is thinner than the thickness of the color filter layer organic light emitting display.
The method of claim 1,
The organic light emitting display device further comprising a color conversion layer disposed to overlap the light recycling layer.
The method of claim 1,
The organic light emitting layer is disposed over the plurality of sub-pixels, the organic light emitting display device for emitting blue light.
9. The method of claim 8,
The color filter layer is an organic light emitting display device that is a color filter layer that transmits blue light.
The method of claim 1,
The first color conversion layer disposed on the first sub-pixel included in the plurality of sub-pixels converts the first light into the second light having a maximum spectral intensity at a wavelength of 620 nm to 640 nm.
The method of claim 1,
The second color conversion layer disposed in the second sub-pixel included in the plurality of sub-pixels converts the first light into third light having a maximum spectral intensity at a wavelength of 540 nm to 560 nm.
The method of claim 1,
The first electrode includes a reflective electrode and a transparent conductive layer,
an organic light emitting display device in which the transparent conductive layer surrounds a side surface of the reflective electrode;
The method of claim 1,
The first electrode includes a reflective electrode and a transparent conductive layer,
The transparent conductive layer is disposed to be in contact with a portion of an upper surface of the reflective electrode.
reflective layer;
a first electrode;
an organic layer disposed on the first electrode;
a second electrode disposed on the organic layer;
a light recycling layer disposed on the second electrode; and
and a color conversion layer disposed between the reflective layer and the first electrode.
15. The method of claim 14,
The light recycling layer is alternately arranged with a high refractive index layer and a low refractive index layer,
An organic light emitting display device in which a high refractive index layer is disposed on the lowermost layer and the uppermost layer of the light recycling layer.
16. The method of claim 15,
The thickness of the high refractive index layer is thinner than that of the low refractive index layer.
16. The method of claim 15,
The thickness of the high refractive index layer has a thickness of 1/4 of the band center wavelength, and the low refractive index layer has a thickness of 1/4 of the band center wavelength.
15. The method of claim 14,
The organic layer emits blue light.
15. The method of claim 14,
The color conversion layer converts the first light into a second light having a maximum spectral intensity at a wavelength of 620 nm to 640 nm or into a third light having a maximum spectral intensity at a wavelength of 540 nm to 560 nm. Device.

Images