KR102526038B1 - Organic light emitting diode display - Google Patents

Abstract

The present invention relates to an organic light emitting diode display capable of improving color viewing angle characteristics, and includes a first substrate including a plurality of light-transmitting areas and a plurality of light-shielding areas alternately disposed, and the plurality of light-shielding areas of the first substrate. A bank disposed corresponding to the plurality of light-emitting layers and a plurality of light-shielding patterns disposed at positions corresponding to the banks and preventing total reflection of light emitted from the plurality of light-emitting layers, wherein the The size of the plurality of light blocking patterns is set in a direction of lowering the luminance of a color with high luminance based on the luminance ratio of the emitted light.

Description

Organic light emitting diode display {ORGANIC LIGHT EMITTING DIODE DISPLAY}

The present invention relates to an organic light emitting diode display, and more particularly, to an organic light emitting diode display capable of improving color viewing angle characteristics.

Recently, various flat panel display devices capable of reducing the weight and volume, which are disadvantages of a cathode ray tube (CRT), are being developed. Examples of such a flat panel display device include a liquid crystal display (LCD), a field emission display (FED), a plasma display panel (PDP), and an organic light emitting diode display (OLED). : Organic Light Emitting Diode Display). Among these flat panel display devices, the organic light emitting diode display (OLED) is a self-emitting display device that excites organic compounds to emit light. has the advantage of simplifying In addition, the organic light emitting diode display is widely used in that it can be manufactured at a low temperature, has a fast response speed of 1 ms or less, and has characteristics such as low power consumption, wide viewing angle, and high contrast. there is.

The organic light emitting diode display includes organic light emitting diodes that convert electrical energy into light energy. An organic light emitting diode includes an anode electrode, a cathode electrode, and an organic light emitting layer disposed between these electrodes. Holes are injected from the anode electrode and electrons are injected from the cathode electrode. When holes injected through the anode electrode and the cathode electrode are injected into the organic light emitting layer (EML), excitons, which are excitons, are formed, and the excitons emit light while emitting energy.

Such an organic light emitting diode display includes a plurality of pixels partitioned by intersections of gate lines, data lines, and common power lines. Each pixel includes a switching thin film transistor, a driving thin film transistor, a storage capacitor, and an organic light emitting diode. The switching thin film transistor is turned on when a scan pulse is supplied to the gate line, and supplies the data signal supplied to the data line to the storage capacitor and the gate electrode of the driving thin film transistor. The driving thin film transistor controls the amount of light emitted from the organic light emitting diode by controlling the current supplied to the organic light emitting diode from the power line in response to the data signal supplied to the gate electrode. The storage capacitor is supplied from the data line through the switching thin film transistor so that the organic light emitting diode (OLED) can maintain light emission by supplying a constant current until the data signal of the next frame is supplied to the driving thin film transistor even when the switching thin film transistor is turned off. Charges the supplied data voltage.

Hereinafter, a conventional organic light emitting diode display will be described with reference to FIGS. 1 and 2 . 1 is a schematic cross-sectional view of a conventional bottom emission type organic light emitting diode display, and FIG. 2 is a schematic cross-sectional view of a conventional top emission type organic light emitting diode display. am.

In FIGS. 1 and 2 , most of other components except for the anode electrode for light emission of the organic light emitting diode display and the bank layer and the black matrix partitioning the light emitting layer are omitted.

Referring to FIG. 1 , a conventional bottom emission type organic light emitting diode display includes an element formation layer ES in which display wires and various elements are disposed on a first substrate SUB1. A bank layer BA defining each pixel area is disposed on the uppermost part of the element formation layer ES, and an anode electrode AN and a light emitting layer OL are disposed at a position corresponding to each pixel area of the element formation layer ES. Light emitting diodes are sequentially arranged.

A conventional bottom emission type organic light emitting diode display also includes an encapsulation substrate (ENC) for encapsulating the light emitting diodes.

In FIG. 1, White1 represents white at the front position recognized as a mixture of red (Ra), green (Ga), and blue (Ba) colors at the front position. White2 represents white at a lateral position recognized as a mixture of red (Rb), green (Gb), and blue (Bb) colors at the lateral position.

In the above-described conventional bottom emission type organic light emitting diode display, red, green, and blue are combined to realize white. However, a combination of red, green, and blue colors to implement white may vary depending on the viewer's viewing angle. This is because the combination ratio of each of red, green, and blue that implements white color varies according to a viewer's position as the display device becomes larger.

Meanwhile, light generated from the light emitting layer of the organic light emitting diode display is refracted, reflected, or absorbed by physical properties of each layer and wires located in the lower layer while passing through the lower layers through red, green, and blue color filters. The degree of this phenomenon varies depending on the angle through which light passes, and affects the white balance. That is, since the combination ratio of red, green, and blue viewed from the front of the display device and the combination ratio of red, green, and blue viewed from the side are different, viewers can perceive the same white color with different feelings.

Referring to FIG. 2 , a conventional top emission type organic light emitting diode display includes an element formation layer ES in which display wires and various elements are disposed on a first substrate SUB1. A bank layer BA defining each pixel area is disposed on the uppermost part of the element formation layer ES, and an anode electrode AN and a light emitting layer OL are disposed at a position corresponding to each pixel area of the element formation layer ES. Light emitting diodes are sequentially arranged.

A black matrix BM having an opening exposing an area corresponding to the pixel area of the first substrate SUB1 is provided on the surface of the second substrate SUB2 facing the first substrate SUB1, and the openings of the black matrix are covered. Red, green, and blue color filters CF are arranged to do so.

The first substrate SUB1 and the second substrate SUB2 are sealed and bonded.

In FIG. 2 , White1 represents white at the front position recognized as a mixture of red (Ra), green (Ga), and blue (Ba) colors at the front position. White2 represents white at a lateral position recognized as a mixture of red (Rb), green (Gb), and blue (Bb) colors at the lateral position.

In the above-described conventional top emission type organic light emitting diode display, as in the bottom emission type organic light emitting diode display, red, green, and blue are combined to realize white. Therefore, since the combination ratio of red, green, and blue viewed from the front of the display device and the combination ratio of red, green, and blue viewed from the side are different, viewers can perceive the same white color with different feelings.

Therefore, the conventional organic light emitting diode display and the organic light emitting diode display have a problem in that it is difficult to maintain a white balance that feels a difference in white visual perception depending on a viewer's position.

An object of the present invention is to solve the above problems, and to provide an organic light emitting diode display capable of maintaining a white balance even in a large size organic light emitting diode display.

An organic light emitting diode display of the present invention for achieving the above object includes a first substrate having a plurality of light-transmitting areas and a plurality of light-shielding areas that are alternately disposed; a bank disposed to correspond to the plurality of light-shielding regions of the first substrate and accommodating a plurality of light emitting layers; and a plurality of light-shielding patterns disposed at positions corresponding to the banks and preventing total internal reflection of emitted light generated from the plurality of light-emitting layers, wherein the size of the plurality of light-shielding patterns is proportional to the luminance ratio of the emitted light. Based on this, the luminance of the color with high luminance is set in the direction of lowering it.

In the configuration, the plurality of light-shielding patterns are arranged to overlap the bank, and a distance between adjacent light-shielding patterns is set to be greater than a width of an opening of a corresponding bank.

In addition, a plurality of light blocking patterns are disposed between the first substrate and the bank.

In addition, an element formation layer is disposed between the first substrate and the bank, and the plurality of light-shielding patterns are disposed between the first substrate and the element formation layer.

In addition, the element formation layer may include a buffer layer covering the plurality of light-shielding patterns, a gate insulating film covering the semiconductor layer of the thin film transistor disposed on the buffer layer, gate lines disposed on the gate insulating film, and a gate electrode of the thin film transistor. An interlayer insulating film covering the interlayer insulating film, a passivation film covering the drain electrode, the source electrode, and the data line disposed on the interlayer insulating film, and an overcoat covering the color filters disposed on the passivation film at positions corresponding to the light-transmitting regions. contains a layer

The organic light emitting diode display further includes a second substrate disposed to face the first substrate, and the plurality of light blocking patterns are disposed on the second substrate at a position corresponding to the bank of the first substrate. do.

Also, the plurality of light blocking patterns are black matrices, and color filters are disposed in openings of the black matrix.

In addition, an element formation layer is disposed between the first substrate and the bank.

In addition, the element formation layer may cover a buffer layer disposed on the substrate, a gate insulating film covering a semiconductor layer of a thin film transistor disposed on the buffer layer, and gate lines disposed on the gate insulating film and a gate electrode of the thin film transistor. and an overcoat layer covering a drain electrode, a source electrode, and a data line disposed on the interlayer insulating film.

와

에 의해 결정되며, 상기 수학식에서, θc는 상기 뱅크의 단부와 상기 차광패턴 단부 사이의 광 경로와 수직선에 의해 형성되는 입사각을 나타내고, 상기 t는 상기 발광층으로부터 상기 출사 광이 굴절되는 지점까지의 두께를 나타내며, n1은 상기 발광층으로부터 상기 출사 광이 굴절되는 지점까지의 매질의 굴절율을 나타내고, n2는 표시장치 외부 영역의 굴절률을 나타내며, n1은 n2보다 크다.In addition, the distance e between an end of a bank defining one of the plurality of light emitting layers and an end of a light-shielding pattern corresponding to the bank is expressed by Equation

and

In the above equation, θc represents an incident angle formed by a light path and a vertical line between an end of the bank and an end of the light-shielding pattern, and t is a thickness from the light emitting layer to a point where the emitted light is refracted where n1 represents the refractive index of a medium from the light emitting layer to the point at which the emitted light is refracted, n2 represents the refractive index of an area outside the display device, and n1 is greater than n2.

Another organic light emitting diode display of the present invention for achieving the above object is a first substrate having a plurality of light-transmitting areas and a plurality of light-shielding areas that are alternately disposed; an encapsulation substrate disposed to face the first substrate; a plurality of light blocking patterns disposed in the plurality of light blocking areas of the first substrate; an element formation layer disposed on the first substrate to cover the plurality of light blocking patterns; and a bank disposed on the element formation layer at positions corresponding to the plurality of light-transmitting regions of the first substrate and having openings accommodating red, green, and blue light-emitting layers, wherein the first substrate and the element formation layer have openings. includes a plurality of light-shielding patterns disposed in the light-shielding regions, the plurality of light-shielding patterns prevent total internal reflection of light emitted from the plurality of light-emitting layers, and the size of the plurality of light-shielding patterns is Based on the luminance ratio of light, it is set in the direction of lowering the luminance of a color with high luminance.

Another organic light emitting diode display of the present invention for achieving the above object is a first substrate having a plurality of light-transmitting areas and a plurality of light-shielding areas that are alternately disposed; an element formation layer disposed on the first substrate; a bank disposed on the element formation layer at positions corresponding to the plurality of light-transmitting regions of the first substrate and having openings accommodating red, green, and blue light emitting layers; a second substrate disposed to face the first substrate; a plurality of light blocking patterns disposed on the second substrate at positions corresponding to the banks of the first substrate; and color filters disposed in the openings of the black matrix, wherein the plurality of light-shielding patterns prevent total internal reflection of emitted light generated from the plurality of light-emitting layers, and the size of the plurality of light-shielding patterns is the size of the light-emitting layer. Based on the luminance ratio of light, it is set in the direction of lowering the luminance of a color with high luminance.

According to the organic light emitting diode display according to the present invention, since the white balance is felt differently depending on the position of the viewing angle, the width of the light-shielding patterns is adjusted in the direction of reducing the luminance ratio of the strongly felt color among red, green, and blue to transmit the light-transmitting area. By adjusting the amount of light passing through them, an effect of improving white balance can be obtained.

1 is a schematic cross-sectional view of a conventional bottom emission type organic light emitting diode display;
2 is a schematic cross-sectional view of a conventional top emission type organic light emitting diode display;
3 is an equivalent circuit diagram showing one pixel of an organic light emitting display device according to an embodiment of the present invention;
4 is a schematic cross-sectional view of an organic light emitting diode display according to a first embodiment of the present invention;
5 is a schematic cross-sectional view of an organic light emitting diode display according to a first embodiment of the present invention;
6 is a cross-sectional view showing a specific area of the organic light emitting diode display shown in FIG. 5;
7 is a view for explaining the setting of a distance between both ends of a bank and both ends of a light blocking pattern of an organic light emitting diode display according to a first embodiment of the present invention;
8 is a schematic cross-sectional view of a top emission type organic light emitting diode display according to a second embodiment of the present invention;
FIG. 9 is a cross-sectional view showing a specific area of the organic light emitting diode display shown in FIG. 8;

Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the accompanying drawings. Like reference numbers throughout the specification indicate substantially the same elements. In the following description, if it is determined that a detailed description of known contents or configurations related to the present invention may unnecessarily obscure the subject matter of the present invention, the detailed description will be omitted.

Hereinafter, an organic light emitting diode display according to a first embodiment of the present invention will be described with reference to FIGS. 3 and 4 .

3 is a schematic diagram of an organic light emitting diode display according to a first embodiment of the present invention. FIG. 4 is a configuration diagram schematically illustrating a pixel shown in FIG. 3 .

Referring to FIG. 3 , the organic light emitting diode display 10 according to the present invention includes a display driving circuit and a display panel DIS.

The display driving circuit includes a data driving circuit 12, a gate driving circuit 14, and a timing controller 16 to write video data voltages of an input image to pixels of the display panel DIS. The data driving circuit 12 converts the digital video data RGB input from the timing controller 16 into an analog gamma compensation voltage to generate a data voltage. The data voltage output from the data driving circuit 12 is supplied to the data lines D1 to Dm. The gate driving circuit 14 sequentially supplies gate pulses synchronized with the data voltage to the gate lines G1 to Gn to select pixels of the display panel DIS to which the data voltage is written.

The timing controller 16 inputs timing signals such as a vertical synchronization signal (Vsync), a horizontal synchronization signal (Hsync), a data enable signal (Data Enable, DE), and a main clock (MCLK) input from the host system 19. and the operation timings of the data driving circuit 12 and the gate driving circuit 14 are synchronized. The data timing control signal for controlling the data driving circuit 12 includes a source sampling clock (SSC), a source output enable signal (SOE), and the like. Gate timing control signals for controlling the gate driving circuit 14 include a gate start pulse (GSP), a gate shift clock (GSC), a gate output enable signal (Gate Output Enable (GOE)), and the like. includes

The host system 19 may be implemented as any one of a television system, a set-top box, a navigation system, a DVD player, a Blu-ray player, a personal computer (PC), a home theater system, and a phone system. The host system 19 includes a system on chip (SoC) with a built-in scaler to convert digital video data RGB of an input image into a format suitable for display on the display panel DIS. The host system 19 transmits timing signals Vsync, Hsync, DE, and MCLK to the timing controller 16 along with the digital video data.

The pixel array of the display panel DIS includes pixels defined by data lines (D1 to Dm, where m is a positive integer) and gate lines (G1 to Gn, where n is a positive integer). Each of the pixels includes an Organic Light Emitting Diode (hereinafter referred to as "OLED"), which is a self-light emitting device.

Referring to FIG. 4 , a plurality of data lines D and a plurality of gate lines G intersect on the display panel DIS, and pixels are arranged in a matrix form at each crossing area. Each pixel sets a light emitting diode (OLED), a driving thin film transistor (hereinafter referred to as a TFT) (DT) that controls the amount of current flowing through the light emitting diode (OLED), and a voltage between the gate and source of the driving TFT (DT). It includes a programming unit (SC) for doing.

The programming unit SC may include at least one switch TFT and at least one storage capacitor. The switch TFT is turned on in response to a scan signal from the gate line (G), thereby applying a data voltage from the data line (D) to one electrode of the storage capacitor. The driving TFT (DT) controls the amount of light emitted by the OLED by controlling the amount of current supplied to the OLED according to the level of the voltage charged in the storage capacitor. The amount of light emitted by the OLED is proportional to the amount of current supplied from the driving TFT (DT). These pixels are connected to a high-potential power source voltage source (EVDD) and a low-potential power source voltage source (EVSS), and receive a high-potential power source voltage and a low-potential power source voltage, respectively, from a power generator (not shown). The TFTs constituting the pixel may be implemented as p-type or as n-type. In addition, the semiconductor layer of the TFTs constituting the pixel may include amorphous silicon, polysilicon, or oxide. The OLED includes an anode electrode (ANO), a cathode electrode (CAT), and an organic light emitting layer interposed between the anode electrode (ANO) and the cathode electrode (CAT). The anode electrode ANO is connected to the driving TFT DT. The organic light emitting layer includes an emission layer (EML), a hole injection layer (HIL), a hole transport layer (HTL), an electron transport layer (ETL), and an electron injection layer. injection layer, EIL) may further include any one or more.

Next, referring to FIGS. 5 and 6 , an organic light emitting diode display according to a first embodiment of the present invention will be described. An organic light emitting diode display according to a first embodiment of the present invention is a bottom emission type organic light emitting diode display.

FIG. 5 is a schematic cross-sectional view of an organic light emitting diode display according to a first embodiment of the present invention, and FIG. 6 is a cross-sectional view showing a specific area of the organic light emitting diode display shown in FIG. 5 .

Referring to FIGS. 5 and 6 , the organic light emitting diode display according to the first embodiment of the present invention includes a first substrate SUB1 and an encapsulation substrate ENC disposed to face each other.

The first substrate SUB1 includes light-transmitting areas TA1 , TA2 , and TA3 through which light passes, and a light-blocking area SA through which light is blocked. On the first substrate SUB1, an element formation layer ES on which various wirings and display elements are disposed is included. The element formation layer ES may include, for example, a buffer layer BUF, a gate insulating layer GI, an interlayer insulating layer ILD, a passivation layer PAS, and an overcoat layer OC.

Light blocking patterns SP1 to SP3 are disposed on the first substrate SUB1 facing the encapsulation substrate ENC.

A buffer layer BUF is disposed on the first substrate SUB1 on which the light blocking patterns SP1 to SP3 are disposed to cover the light blocking patterns SP1 to SP3.

A semiconductor layer S of a driving TFT (D_TFT) and a switch TFT (not shown) of the programming unit SC is disposed on the buffer layer BUF. The semiconductor layer S includes a semiconductor active region AA, and a drain region DA and a source region SA disposed on both sides of the semiconductor active region, respectively.

A gate insulating layer GI is disposed on the buffer layer BUF on which the semiconductor layer S is disposed to cover the semiconductor layer S.

Gate lines and the gate electrode GE of the driving TFT (D_TFT) are disposed on the gate insulating layer GI. The gate electrode GE is disposed to overlap the semiconductor active region AA of the semiconductor layer S.

An interlayer insulating layer ILD is disposed on the gate insulating layer GI on which the gate lines and gate electrodes GE are disposed to cover the gate lines and gate electrodes GE.

On the interlayer insulating layer ILD, the drain electrode DE and the source electrode SE are disposed to be separated from each other. The drain electrode DE is connected to the drain region DA of the semiconductor layer S exposed through a first contact hole penetrating the interlayer insulating layer ILD and the gate insulating layer GI. The source electrode SE is connected to the source region SA of the semiconductor layer S exposed through a second contact hole penetrating the interlayer insulating layer ILD and the gate insulating layer GI. Data lines (not shown) may be disposed on the interlayer insulating layer ILD in a direction crossing the gate lines.

A passivation layer PAS is disposed on the interlayer insulating layer ILD on which the data line, the drain electrode DE, and the source electrode SE are disposed to cover them.

Red, green, and blue color filters CF are disposed on the passivation layer PAS to correspond to the light-transmitting areas TA1 , TA2 , and TA3 .

An overcoat layer OC is disposed on the passivation layer PAS on which the color filters CF are disposed to cover the color filters CF.

An anode electrode AN is disposed on the overcoat layer OC to correspond to the light-transmitting areas TA1 , TA2 , and TA3 . The anode electrode AN is connected to the exposed drain electrode DE through the third contact hole penetrating the overcoat layer OC.

On the overcoat layer OC on which the anode electrode AN is disposed, banks BA having openings exposing the anode electrode AN are disposed corresponding to the light-transmitting areas TA1 , TA2 , and TA3 . The light-shielding patterns SP1, SP2, SP3, and SP4 are disposed to overlap the bank BA, and a distance between adjacent light-shielding patterns is set greater than a width of an opening of a corresponding bank.

The organic emission layer OL is disposed on the anode electrode AN, and the cathode electrode CL is disposed on the organic emission layer OL.

The encapsulation substrate ENC is configured to encapsulate components disposed on the first substrate SUB.

In the organic light emitting diode display according to the first embodiment of the present invention, each end of the light blocking patterns SP1 to SP3 and the bank BA (transmitting areas TA1 through which red, green, and blue light passes) ~ TA3)) is determined in consideration of material characteristics of each element disposed on the element formation layer ES (hereinafter, referred to as element characteristics).

Since black body radiation does not occur in a light source for illumination or display, in order to express white balance quantitatively, for example, Correlated Color Temperature (CCT) of the CIE (CoBMission　Internationale　de　I'Eclairage) coordinate system ) is used. The correlated color temperature is determined by the luminance ratio of red, green, and blue transmitted through the light-transmitting areas TA1, TA2, and TA3, and when the brightness of one or more colors of red, green, and blue is higher or lower, the same white color temperature This can feel redder or bluer, and this difference is marked as K. To the viewer's eyes, a lower color temperature is perceived as red, and a higher color temperature is perceived as blue.

For example, when the reference CCT at a viewing angle of 0° (when the refraction angle is 0°) for an organic light emitting diode display is 10000K and the CCT at a viewing angle of 60° (when the refraction angle is 60°) is 13000K, white Since the feeling of blue is strongly perceived as the balance, the white balance can be maintained by adjusting the amount of light passing through the light-transmitting area by adjusting the width of the light-shielding patterns SP1 to SP3 in the direction of decreasing the luminance ratio of blue.

Hereinafter, the setting of the distance between the end of the bank BA and the end of the light-shielding patterns SP1, SP2, SP3, and SP4 of the organic light emitting diode display according to the first embodiment of the present invention will be described in more detail with reference to FIG. to be explained as

FIG. 7 is a diagram for explaining distance setting between the bank BA and the light-shielding patterns SP1, SP2, SP3, and SP4 of the organic light emitting diode display according to the first embodiment of the present invention.

Referring to FIG. 7 , θc represents an incident angle with respect to the boundary line between the element formation layer EF and the atmosphere, and θ represents a refraction angle of light emitted into the atmosphere. t is the sum of the thickness of the element formation layer EF and the thickness of the first substrate SUB1. a represents the distance from the right end of the bank BA located on the left side of the first light-transmitting area TA1 through which red light passes through to the right end of the first light-shielding pattern SP1 located below it, and b is It represents the distance from the left end of the bank BA located on the right side of the first light-transmitting area TA1 to the left end of the second light-shielding pattern SP2 located below it. c represents the distance from the right end of the bank BA located on the left side of the second transmission area TA2 through which green passes through to the right end of the second light-shielding pattern SP2 located below it, and d represents the green It represents the distance from the left end of the bank BA located on the right side of the penetrating second light transmission area TA2 to the left end of the third light blocking pattern SP3 located below it. e represents the distance from the right end of the bank BA located on the left side of the third transmission area TA3 through which blue is transmitted to the right end of the third light blocking pattern SP3 located below it.

When light is emitted from inside the organic light emitting diode display to the outside, the refractive index (n1) including the element formation layer (EF) and the first substrate (SUB1) and the refractive index (n2) of the air outside the first substrate (SUB1) are different. Therefore, the transmitted light is refracted as shown in FIG. 7 . In order to increase light transmittance of the organic light emitting diode display, the transmitted light passing through the element formation layer EF and the first substrate SUB preferably has an incident angle θc that does not cause total reflection. To this end, the incident angle θc of the total refractive index of the element formation layer EF and the first substrate SUB must be smaller than the critical angle (the incident angle when the refractive angle is 90°).

The refractive index n1 of the element formation layer EF and the first substrate SUB1 varies depending on the material constituting them. Therefore, if the distance a to e is set by adjusting the size of each of the first to third light-shielding patterns SP1, SP2, SP3, and SP4, the angle of refraction of light emitted from the inside to the outside of the organic light emitting diode display can be controlled. be able to

For example, as shown in FIG. 7 , the distance e between the end of the bank BA and the end of the light blocking pattern SP may be determined according to Equations 1 and 2 below. Of course, the distances a to d and f may also be determined according to Equations 1 and 2 below. In this case, e is replaced by a, b, c, d, f.

In Equations 1 and 2, the distance e is the distance between the right end of the bank BA located on the left side of the third light transmission area TA3 and the third light blocking pattern SP3 located on the left side of the third light transmission area TA3. is the distance between the right ends. t is the sum of the thickness of the element formation layer (EF) and the thickness of the first substrate (SUB1), and θc is the incident light generated from the light emitting layer (EL) passing through the element formation layer (EF) and the first substrate (SUB1) , where n1 is the refractive index of the inside of the display device including the element formation layer EF and the first substrate SUB1, and n2 is the refractive index of air.

On the other hand, the refraction angle can be replaced by the viewing angle for the display device, and since the white balance is felt differently depending on the viewing angle, adjust the values of the distances a to f in the direction of reducing the luminance ratio of the strongly felt color among red, green, and blue. The white balance can be maintained by adjusting the amount of light passing through the light-transmitting area.

For example, when the red color is felt strongly, if the distances a and b are reduced, the amount of red light transmitted through the first light transmission area TA1 is reduced, and the white balance can be improved. In addition, when the green color is felt strongly, if the distances c and d are reduced, the amount of green light transmitted through the second transmission area TA2 is reduced, and the white balance can be improved. In addition, when the blue color is felt strongly, if the distances e and f are reduced, the amount of blue light transmitted through the third light transmission area TA3 is reduced, and the white balance can be improved.

Table 1 is a table showing the CIE coordinate system measured while increasing the viewing angle from 0° to 85° in the conventional organic light emitting diode display, and Table 2 shows the viewing angle in the organic light emitting diode display according to the first embodiment of the present invention This table shows the CIE coordinate system measured while increasing from 0° to 85°.

In Tables 1 and 2, x and y represent the CIE xy chromaticity distribution, u' and v' are chromaticity coordinates obtained by converting the values obtained from the CIE xy chromaticity distribution, and u'v' is obtained from u' and v' is the color difference value.

The color difference value is 18 μm for the width of the bank BA, 58 μm for the width of the first transmission area TA1 through which red is transmitted, 58 μm for the width of the second transmission area TA2 through which green is transmitted, and 58 μm for transmission of blue. The width of the third transmissive area TA3 is 116 μm, the thickness of the element formation layer ES is 5.2 μm, the distances a and b are 1.5 μm, the distances c and d are 1.5 μm, and the distances e and f are 4.7 μm, respectively. This is the value obtained after setting to μm.

CIE coordinate system viewing angle x y u' v' △u'v' 0° 0.281 0.288 0.191 0.440 0 30° 0.273 0.270 0.192 0.426 0.013 60° 0.259 0.250 0.189 0.411 0.029 85° 0.258 0.248 0.189 0.409 0.031

CIE coordinate system viewing angle x y u' v' △u'v' 0° 0.281 0.288 0.191 0.440 0 30° 0.272 0.270 0.191 0.427 0.013 60° 0.266 0.262 0.190 0.420 0.019 85° 0.268 0.265 0.190 0.423 0.017

When the color difference value is 0, it means that the white balance is well maintained because blue, green, and white expression by blue are accurate, and as the color difference value increases, it means that the white balance is not good.

Referring to Tables 1 and 2, the white balance deteriorates as the viewing angle increases, and even when the viewing angle increases, the white balance of the organic light emitting diode display according to the first embodiment of the present invention is higher than that of the conventional organic light emitting diode display. It can be seen that it has improved.

Next, an organic light emitting diode display according to a second embodiment of the present invention will be described with reference to FIGS. 8 and 9 . An organic light emitting diode display according to a second embodiment of the present invention is a top emission type organic light emitting diode display.

Referring to FIGS. 8 and 9 , an organic light emitting diode display according to a second embodiment of the present invention includes a first substrate SUB1 and a second substrate SUB2 disposed to face each other. The second substrate SUB2 may use the same encapsulation substrate ENC as described in the first embodiment.

The first substrate SUB1 includes light-transmitting areas TA1 , TA2 , and TA3 through which light passes, and a light-blocking area SA through which light is blocked. On the first substrate SUB1, an element formation layer ES on which various wirings and display elements are disposed is included. The element formation layer ES may include, for example, a buffer layer BUF, a gate insulating layer GI, an interlayer insulating layer ILD, and an overcoat layer OC.

A buffer layer BUF is disposed on the first substrate SUB1 facing the second substrate SUB2.

A semiconductor layer S of a driving TFT (D_TFT) and a switch TFT (not shown) of the programming unit SC is disposed on the buffer layer BUF. The semiconductor layer S includes a semiconductor active region AA, and a drain region DA and a source region SA disposed on both sides of the semiconductor active region, respectively.

A gate insulating layer GI is disposed on the buffer layer BUF on which the semiconductor layer S is disposed to cover the semiconductor layer S.

Gate lines and the gate electrode GE of the driving TFT (D_TFT) are disposed on the gate insulating layer GI. The gate electrode GE is disposed to overlap the semiconductor active region AA of the semiconductor layer S.

An interlayer insulating layer ILD is disposed on the gate insulating layer GI on which the gate lines and gate electrodes GE are disposed to cover the gate lines and gate electrodes GE.

On the interlayer insulating layer ILD, the drain electrode DE and the source electrode SE are disposed to be separated from each other. The drain electrode DE is connected to the drain region DA of the semiconductor layer S exposed through a first contact hole penetrating the interlayer insulating layer ILD and the gate insulating layer GI. The source electrode SE is connected to the source region SA of the semiconductor layer S exposed through a second contact hole penetrating the interlayer insulating layer ILD and the gate insulating layer GI. Data lines (not shown) may be disposed on the interlayer insulating layer ILD in a direction crossing the gate lines.

An overcoat layer OC is disposed on the interlayer insulating layer ILD on which the data line, drain electrode DE, and source electrode SE are disposed to cover them.

An anode electrode AN is disposed on the overcoat layer OC to correspond to the light-transmitting areas TA1 , TA2 , and TA3 . The anode electrode AN is connected to the exposed drain electrode DE through the third contact hole penetrating the overcoat layer OC.

On the overcoat layer OC on which the anode electrode AN is disposed, banks BA having openings exposing the anode electrode AN are disposed corresponding to the light-transmitting areas TA1 , TA2 , and TA3 . The light-shielding patterns SP1, SP2, SP3, and SP4 are disposed to overlap the bank BA, and a distance between adjacent light-shielding patterns is set greater than a width of an opening of a corresponding bank.

The organic emission layer OL is disposed on the anode electrode AN, and the cathode electrode CL is disposed on the organic emission layer OL.

Openings disposed on the surface of the second substrate SUB2 facing the first substrate SUB1 at positions corresponding to the light-blocking area SA and the banks BA to expose the light-transmitting areas TA1, TA2, and TA3. A black matrix (BM) having .

In the organic light emitting diode display according to the second embodiment of the present invention, the black matrix (BM) plays the same role as the light blocking patterns of the organic light emitting diode display according to the first embodiment of the present invention. Therefore, hereinafter, the black matrix BM, the light-shielding patterns SP1, SP2, SP3, and SP4, or the light-shielding patterns SP1, SP2, SP3, and SP4 of the black matrix BM will be referred to as necessary.

In the organic light emitting diode display device according to the second embodiment of the present invention, ends of each of the light blocking patterns SP1 to SP3 and transmissive areas TA1 to TA3 through which red, green, and blue light is transmitted are defined. Similar to the organic light emitting diode display according to the first embodiment, the distances a to f between the ends of the banks BA are the angle of incidence θc, the refractive indices n1 and n2, and the second substrate SUB2 from the organic light emitting layer OL. It can be determined according to Equations 1 and 2 using the thickness t to the upper surface of

In the organic light emitting diode display according to the second embodiment of the present invention, the distance between the bank and the blocking patterns is the bank BA and the blocking patterns SP1 and SP2 of the organic light emitting diode display according to the first embodiment of the present invention. , SP3, SP4), the principle is the same except that there is a difference according to the structural difference between the top emission type organic light emitting diode display and the top emission type organic light emitting diode display. is omitted.

In the organic light emitting diode display according to the second embodiment of the present invention, as in the organic light emitting diode display according to the first embodiment of the present invention, the white balance is felt differently depending on the position of the viewing angle, so that among red, green, and blue The widths of the light-shielding patterns SP1 to SP3 of the black matrix BM may be adjusted in a direction of decreasing the luminance ratio of a color that is felt strongly. By adjusting the amount of light passing through the light-transmitting areas TA1 , TA2 , and TA3 as described above, an effect of improving white balance can be obtained.

That is, when the red color is felt strongly, if the distances a and b are reduced, the amount of red light transmitted through the first light transmission area TA1 is reduced, and the white balance can be improved. In addition, when the green color is felt strongly, if the distances c and d are reduced, the amount of green light transmitted through the second transmission area TA2 is reduced, and the white balance can be improved. In addition, when the blue color is felt strongly, if the distances e and f are reduced, the amount of blue light transmitted through the third light transmission area TA3 is reduced, and the white balance can be improved.

Table 3 is a table showing the CIE coordinate system measured while increasing the viewing angle from 0° to 85° in a conventional top emission organic light emitting diode display, and Table 4 is an organic light emitting diode display according to the second embodiment of the present invention This table shows the CIE coordinate system measured while increasing the viewing angle from 0° to 85° on the device.

As for the color difference value, the width of the bank BA is 28 μm, the width of the first transmission area TA1 through which red is transmitted is 47 μm, the width of the second transmission area TA2 through which green is transmitted is 47 μm, and blue is transmitted through The width of the third transmissive area TA3 is 47 μm, the distance from the organic light emitting layer OL to the second substrate SUB2 is 10 μm, the distances a and b are 2.5 μm, and the distances c and d are 2.5 μm, respectively. , the values obtained after setting the distances e and f to 6 μm, respectively.

CIE coordinate system viewing angle x y u' v' △u'v' 0° 0.281 0.288 0.191 0.440 0 30° 0.273 0.270 0.192 0.426 0.013 60° 0.259 0.250 0.189 0.411 0.029 85° 0.258 0.248 0.189 0.409 0.031

CIE coordinate system viewing angle x y u' v' △u'v' 0° 0.281 0.288 0.191 0.440 0 30° 0.272 0.270 0.191 0.427 0.013 60° 0.266 0.262 0.190 0.420 0.019 85° 0.268 0.265 0.190 0.423 0.017

In Tables 3 and 4, when the color difference value is 0, it means that the white balance is maintained well because the white expression by blue, green, and blue is accurate, and as the color difference value increases, the white balance is not good. .

Referring to Tables 3 and 4, the white balance deteriorates as the viewing angle increases, and even when the viewing angle increases, the white balance of the organic light emitting diode display according to the second embodiment of the present invention is higher than that of the conventional organic light emitting diode display. It can be seen that it has improved.

Through the above description, those skilled in the art will be able to know that various changes and modifications are possible within a range that does not deviate from the technical spirit of the present invention. Therefore, the present invention should not be limited to the contents described in the detailed description, but should be defined by the claims.

SUB1: 1st board SUB2: 2nd board
ENC: encapsulation substrate SA: shading area
TA1, TA2, TA3: transmission area EF: element formation layer
BM: Black matrix SP1, SP2, SP3, SP4: Shading pattern

Claims (13)

a first substrate having a plurality of light-transmitting areas and a plurality of light-shielding areas alternately disposed;
A plurality of anode electrodes disposed on the overcoat layer on the first substrate to correspond to each of the plurality of light-transmitting regions; disposed to correspond to each of the plurality of light-transmitting regions on the overcoat layer, and to connect the plurality of anode electrodes a bank having a plurality of openings exposing; and
A plurality of light-shielding patterns disposed at positions corresponding to the plurality of light-shielding regions to overlap the bank and preventing total internal reflection of emitted light generated from the plurality of light-emitting layers disposed on the plurality of anode electrodes. and
The size of the plurality of light-shielding patterns is set in a direction of lowering the luminance of a color with high luminance based on the luminance ratio of the emitted light,
Among the plurality of light-shielding patterns, a distance between adjacent light-shielding patterns is greater than a corresponding width of the opening,
The organic light emitting diode display device wherein a width of the light-shielding pattern increases as the width of the opening of the bank increases. According to claim 1,
The plurality of light blocking patterns are disposed to overlap the bank, and a distance between adjacent light blocking patterns is greater than a width of an opening of a corresponding bank. According to claim 1,
The plurality of light blocking patterns are disposed between the first substrate and the bank. According to claim 1,
An element formation layer is disposed between the first substrate and the bank, and the plurality of light blocking patterns are disposed between the first substrate and the element formation layer. According to claim 4,
The element formation layer,
a buffer layer covering the plurality of light blocking patterns;
A gate insulating film covering the semiconductor layer of the thin film transistor disposed on the buffer layer;
An interlayer insulating film covering gate lines disposed on the gate insulating film and a gate electrode of a thin film transistor;
A passivation film covering a drain electrode, a source electrode, and a data line disposed on the interlayer insulating film, and
and the overcoat layer covering color filters disposed on the passivation film at positions corresponding to the light-transmitting regions. According to claim 1,
Further comprising a second substrate disposed to face the first substrate,
The plurality of light blocking patterns are disposed on the second substrate at positions corresponding to the banks of the first substrate. According to claim 6,
The plurality of light blocking patterns are black matrices, and color filters are disposed in openings of the black matrix. According to claim 7,
An organic light emitting diode display comprising an element formation layer disposed between the first substrate and the bank. According to claim 8,
The element formation layer,
a buffer layer disposed on the substrate;
A gate insulating film covering the semiconductor layer of the thin film transistor disposed on the buffer layer;
An interlayer insulating film covering the gate lines disposed on the gate insulating film and the gate electrode of the thin film transistor, and
and the overcoat layer covering a drain electrode, a source electrode, and a data line disposed on the interlayer insulating layer. According to any one of claims 1 to 9,
The distance e between the end of a bank defining any one of the plurality of light emitting layers and the end of the light blocking pattern corresponding to the bank is Equation

and

is determined by
In the above equation, θc represents an incident angle formed by a light path and a vertical line between an end of the bank and an end of the light blocking pattern, t represents a thickness from the light emitting layer to a point where the emitted light is refracted, and n1 is represents a refractive index of a medium from the light emitting layer to a point where the emitted light is refracted, n2 represents a refractive index of a region outside the display device, and n1 is greater than n2. a first substrate having a plurality of light-transmitting areas and a plurality of light-shielding areas alternately disposed;
an encapsulation substrate disposed to face the first substrate;
a plurality of light blocking patterns disposed in the plurality of light blocking areas of the first substrate;
an element formation layer disposed on the first substrate to cover the plurality of light blocking patterns; and
a bank disposed on the element formation layer at positions corresponding to the plurality of light-transmitting regions of the first substrate and having openings exposing red, green, and blue light-emitting layers;
a plurality of light blocking patterns disposed in the plurality of light blocking regions to overlap the bank between the first substrate and the element formation layer;
The plurality of light-shielding patterns prevent total reflection of emitted light generated from the plurality of light-emitting layers,
The size of the plurality of light-shielding patterns is set in a direction of lowering the luminance of a color with high luminance based on the luminance ratio of the emitted light ,
Among the plurality of light-shielding patterns, a distance between adjacent light-shielding patterns is greater than a corresponding width of an opening of the bank;
The organic light emitting diode display device wherein a width of the light-shielding pattern increases as the width of the opening of the bank increases. a first substrate having a plurality of light-transmitting areas and a plurality of light-shielding areas alternately disposed;
an element formation layer disposed on the first substrate;
a bank disposed on the element formation layer at positions corresponding to the plurality of light-transmitting regions of the first substrate and having openings exposing red, green, and blue light emitting layers;
a second substrate disposed to face the first substrate;
a plurality of light blocking patterns disposed on the second substrate at positions corresponding to the banks of the first substrate and disposed at positions corresponding to the plurality of light blocking regions; and
and color filters disposed between the plurality of light blocking patterns,
The plurality of light-shielding patterns prevent total reflection of light emitted from the red, green, and blue light emitting layers,
The size of the plurality of light-shielding patterns is set in a direction of lowering the luminance of a color with high luminance based on the luminance ratio of the emitted light,
Among the plurality of light-shielding patterns, a distance between adjacent light-shielding patterns is greater than a corresponding width of an opening of the bank;
An organic light emitting diode display device in which a distance between adjacent light blocking patterns increases as the width of the opening of the bank increases. The method of any one of claims 1, 11 and 12,
The plurality of light-transmitting areas include a first light-transmitting area through which red light passes, a second light-transmitting area through which green light transmits, and a third light-transmitting area through which blue light is transmitted,
The plurality of light-shielding patterns are disposed on one side of the first light-transmitting area and overlap the first area of the bank, and between the first light-transmitting area and the second light-transmitting area, the first light-shielding pattern overlaps with the first area of the bank. a second light-shielding pattern overlapping the second region, a third light-shielding pattern disposed between the second light-transmitting region and the third light-transmitting region and overlapping the third region of the bank, and disposed on the other side of the third light-transmitting region A fourth blocking pattern overlapping the fourth region of the bank;
When a large amount of red light is included in the light transmitted through the first to third light-transmitting areas, a first light from the right end of the bank located on the left side of the first light-transmitting area to the right end of the first light-shielding pattern adjacent thereto The horizontal distance and the second horizontal distance from the left end of the bank located on the right side of the first light-transmitting area to the left end of the second light-shielding pattern adjacent thereto are the right end of the bank located on the left side of the second light-transmitting area a third horizontal distance from the bank to the right end of the second light-shielding pattern adjacent thereto, a fourth horizontal distance from the left end of the bank located on the right side of the second light-transmitting area to the left end of the third light-shielding pattern adjacent thereto, A fifth horizontal distance from the right end of the bank located on the left side of the third light-transmitting area to the right end of the third light-shielding pattern adjacent thereto, and from the left end of the bank located on the right side of the third light-transmitting area set to be smaller than the sixth horizontal distance to the left end of the fourth light-shielding pattern adjacent thereto;
When there is a large amount of green light transmitted through the first to third transmission areas, the third and fourth horizontal distances are set smaller than the first and second horizontal distances and the fifth and sixth horizontal distances. and
and setting the fifth and sixth horizontal distances to be smaller than the first to fourth horizontal distances when a large amount of blue light is included in the light passing through the first to third transmitting areas.

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