KR100741097B1 - Organic light emitting display device - Google Patents

Abstract

The present invention is to broaden the color reproduction range of the display to express a natural color, and includes a substrate, three first pixels arranged on the substrate and emitting red, green, and blue light, respectively, An organic light emitting display device includes at least one second pixel that is arranged and emits a color different from the emission colors of the first pixel.

Description

Organic light emitting display device

1 is a schematic cross-sectional view of a top-emitting organic light emitting display device;

2 is a cross-sectional view illustrating pixels of an organic light emitting diode display according to the present invention;

3 is a plan view illustrating pixels of an organic light emitting diode display according to the present invention;

4 is a cross-sectional view of one unit pixel of the organic light emitting diode display of the present invention.

The present invention relates to an organic light emitting display device, and more particularly, to an organic light emitting display device capable of wider color reproduction range.

As a spontaneous light emitting display device, an organic light emitting display device has a wide viewing angle, excellent contrast, and fast response speed. In particular, the organic light emitting display is a self-luminous display that electrically excites fluorescent organic compounds to emit light, which can be driven at low voltage, is easy to thin, and has been pointed out as a problem in liquid crystal display devices such as wide viewing angle and fast response speed. It is attracting attention as the next generation display that can solve the shortcomings.

In the organic light emitting diode display, a color of a corresponding pixel is realized in an organic compound serving as a light emitting layer. Accordingly, when a pixel is composed of three primary colors of red, green, and blue, red, green, and blue light emitting layers are disposed on each pixel. do.

In the pixel configuration method, white can be realized by mixing light emitted from the pixel. The simplest example consists of red, green, and blue, the three primary colors of light, and another example is cyan, magenta (the complementary colors of these red, green, and blue). The pixel is composed of Magenta and Yellow. This is because light can realize white color by mixing cyan, magenta, and yellow.

In the organic light emitting diode display, pixels are composed of colors that can form white, and then, by adjusting and mixing the gray levels of the pixels, a full color is realized.

However, in the conventional organic light emitting diode display, since pixels are implemented using the three colors that can implement white, the color purity of each pixel affects the color reproduction range, and thus, the color reproduction range must be limited. There was no.

The present invention has been made to solve the above problems, and an object of the present invention is to provide an organic light emitting display device capable of expressing a color close to a natural color by widening a color reproduction range of a display.

In order to achieve the above object, the present invention provides a substrate, three first pixels arranged on the substrate and emitting red, green, and blue light, respectively, and a first pixel arranged on the substrate. An organic light emitting display device comprising at least one second pixel for emitting a color different from the emission colors of is provided.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 schematically illustrates an organic light emitting diode (OLED) of an organic light emitting diode display having a conventional top emission structure.

In the top emission type organic light emitting diode display, as shown in the arrow direction of FIG. 1, an image is implemented in a direction opposite to the substrate 1, and a reflective film 2 is formed on the substrate 1, and the image is formed on the reflective film 2. The first electrode 3 serving as the anode electrode and the second electrode serving as the cathode electrode are opposed to each other, and the organic light emitting film () is disposed between the first electrode 3 and the second electrode 5. 4) is interposed.

The reflective film 2 is provided to increase the light efficiency of the light emitted from the organic light emitting film 4 and to form a resonant structure as described later. The reflective film 2 is preferably formed to a thickness capable of light reflection with a material having good electrical conductivity. . It is preferable to be provided with metal materials such as Ag, Mg, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, and compounds thereof.

Since the first electrode 3 is an anode electrode, the first electrode 3 may be formed of a material having a high work function, and may be formed of a transparent conductor such as ITO, IZO, In 2 O 3, and ZnO.

Since the second electrode 5 becomes a cathode electrode, the second electrode 5 may be made of a metal material such as Ag, Mg, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, and a compound thereof having a low work function. It is possible to form a thin, transmissive reflective film of Mg, Ag, Al, etc., so as to transmit light after optical resonance.

The organic light emitting film 4 may be a low molecular or high molecular organic film. When using a low molecular organic film, a hole injection layer (HIL), a hole transport layer (HTL), an emission layer (EML), an electron transport layer (ETL), an electron injection layer (EIL) : Electron Injection Layer) can be formed by stacking single or complex structure, and usable organic materials are copper phthalocyanine (CuPc), N, N-di (naphthalen-1-yl) -N, N '-Diphenyl-benzidine (N, N'-Di (naphthalene-1-yl) -N, N'-diphenyl-benzidine: NPB), tris-8-hydroxyquinoline aluminum ( Alq3) can be used in various ways. These low molecular weight organic films are formed by the vacuum deposition method.

In the case of the polymer organic film, the structure may include a hole transporting layer (HTL) and a light emitting layer (EML). In this case, PEDOT is used as the hole transporting layer, and polyvinylvinylene (PPV) and polyfluorene are used as the light emitting layer. Polymer organic materials such as (Polyfluorene) are used and can be formed by screen printing or inkjet printing.

The organic layer as described above is not necessarily limited thereto, and various embodiments may be applied.

After the organic light emitting diode OLED is formed, the organic light emitting diode OLED is sealed and shielded from outside air.

In the above structure, optical resonance is caused to occur by adjusting the distance T1 between the interface between the reflective film 2 and the first electrode 3 and the interface between the second electrode 5 and the organic light emitting film 4. Can be. This T1 is called resonance distance. By adjusting the resonance distance T1, the light emitted from the organic light emitting film 4 can be further increased in brightness by optical resonance. In addition, the light emitted from the organic light emitting film 4 can be adjusted by adjusting the resonance distance T1. Even the color of light in the direction of the arrow can be adjusted. The resonance distance T1 can be easily adjusted by adjusting the thickness T2 of the organic light emitting film 4.

The present inventors focus on the fact that the color of light emitted by varying the optical resonance distance can be adjusted, and in addition to the existing red, green, and blue pixels, a pixel capable of realizing a separate color can be added.

2 and 3 have a configuration in which a cyan pixel C, an orange pixel O, and a yellow pixel Y are further added in addition to the existing red pixel R, green pixel G, and blue pixel B. FIG. It is shown schematically.

The existing red pixels R, green pixels G, and blue pixels B are called first pixels, and the added cyan pixels C, orange pixels O, and yellow pixels Y are second pixels. In this regard, these second pixels can be obtained simply by adjusting the resonance thickness in the existing first pixel.

As described above, in the front light emitting structure as shown in FIG. 1, the resonance distance T1 can be obtained simply by adjusting the thickness T2 of the organic light emitting film 4. In this case, the red pixel R of the first pixel is configured to have a thickness of the organic light emitting film 4 of 1100 to 1400 s or 2800 to 3200 s, and the green pixel G has a thickness of the organic light emitting film 4 of 800 to 1100 Hz or 2300-2700 Hz. In addition, the blue pixel B has a thickness of the organic light emitting film 4 of 600 to 800 kPa or 1700 to 2100 kPa.

In this thickness structure, the above-mentioned second pixels cyan pixel (C), orange pixel (O), and yellow pixel (Y) are also obtained simply by adjusting the thickness of the organic light emitting film 4 at the first pixels. You can lose.

When the red pixel R, the green pixel G, and the blue pixel B are configured to the thickness of the organic light emitting film 4 as described above, the cyan pixel C is formed in the structure of the organic light emitting film of the blue pixel B. If the thickness is in the range of 800 to 1000 kPa or 1400 to 1700 kPa, it can be implemented.

In addition, the orange pixel O may be implemented when the thickness of the organic pixel of the red pixel R is in the range of 1400 to 1700 s or 2300 to 2800 s.

The yellow pixel Y may be implemented when the thickness of the organic light emitting layer structure of the green pixel G is in the range of 1100 to 1400 s or 1800 to 2300 s.

In addition, although not shown in the drawings, the second pixel may be provided as pixels of purple or magenta color. The purple pixel can be implemented when the thickness of the organic light emitting film structure of the blue pixel B is in the range of 1000 to 1400 μs, and the magenta pixel is formed by co-deposition of the red light emitting material in the organic light emitting film structure of the blue pixel B. It can be implemented.

As described above, according to the present invention, in addition to the red, green, and blue pixels, various colors may be further arranged to provide an expression close to natural colors.

As shown in FIG. 4, the present invention may be provided in an AM structure.

A buffer layer 11 made of an organic compound and / or an inorganic compound is further formed on the substrate 1, preferably formed of SiOx (x ≧ 1) or SiNx (x ≧ 1).

After the semiconductor active layer 12 arranged in a predetermined pattern is formed on the buffer layer 11, the semiconductor active layer 12 is embedded by the gate insulating layer 13. The semiconductor active layer 12 has a source region 12b and a drain region 12c, and further includes a channel region 12a therebetween. The semiconductor active layer 12 may be formed by forming an amorphous silicon film on the buffer layer 11, crystallizing it to form a polycrystalline silicon film, and patterning the polycrystalline silicon film. The source and drain regions 12b and 12c of the semiconductor active layer 12 are doped with impurities in accordance with the type of TFT such as a driving TFT and a switching TFT.

The gate electrode 14 corresponding to the semiconductor active layer 12 and the interlayer insulating layer 15 filling the gate insulating layer 13 are formed on the upper surface of the gate insulating layer 13.

After contact holes are formed in the interlayer insulating layer 15 and the gate insulating layer 13, the source electrode 16 and the drain electrode 17 are respectively formed on the interlayer insulating layer 15 and the source region 12b. And contact with the drain region 12c.

The passivation film 18 is formed on the thus formed thin film transistor, and the reflective film 2 and the first electrode 3 are sequentially formed on the passivation film 18. The first electrode 3 is brought into contact with the drain electrode 17 of the TFT by via holes formed in the passivation film 18. The passivation film 18 may be formed of an inorganic material and / or an organic material. As shown in FIG. 4, the passivation film 18 may be formed as a flattening film so that the top surface is flat regardless of the bending of the lower film. It may be formed to go along the bend.

After the first electrode 3 is formed on the passivation film 18, the pixel defining layer 19 is formed of an organic material and / or an inorganic material to cover the first electrode 3 and the passivation film 18. The first electrode 3 is opened to expose the first electrode 3.

The organic light emitting film 4 and the second electrode 5 are formed on at least the first electrode 3.

After the organic light emitting diode OLED is formed, the organic light emitting diode OLED is sealed and shielded from outside air.

Although the above embodiments have been described with respect to an organic light emitting display, the present invention can be applied to various kinds of flat panel displays such as a liquid crystal display in addition to the organic light emitting display.

According to the present invention as described above, by configuring the pixels of various colors, it is possible to widen the range of color reproduction, thereby realizing an image close to natural colors.

In addition, since the pixels of various colors can be manufactured using conventional three primary pixels, the manufacturing process can be simplified.

Although the present invention has been described with reference to one embodiment shown in the accompanying drawings, this is merely exemplary, and it will be understood by those skilled in the art that various modifications and equivalent other embodiments are possible. Could be. Therefore, the true scope of protection of the present invention should be defined only by the appended claims.

Claims (8)

delete delete Board; Three first pixels arranged on the substrate and emitting red, green, and blue colors, respectively; And At least one second pixel arranged on the substrate, the second pixel emitting a color different from the emission colors of the first pixel; The second pixel is provided with at least one of emitting colors of any one of orange, yellow, cyan, purple, and magenta, The first pixel and the second pixel implement an image in a direction opposite to the substrate, The emission layer of the pixel emitting red light among the first pixels is 1100 to 1400 Hz, or 2800 to 3200 Hz, The light emitting layer of the pixel emitting green light among the first pixels is 800 to 1100 Hz, or 2300 to 2700 Hz, And a light emitting layer of the pixel emitting blue light among the first pixels is 600 to 800 mW, or 1700 to 2100 mW. The method of claim 3, The emission layer of the pixel emitting orange color among the second pixels is the same material as the material of the emission layer of the pixel emitting red color among the first pixels and has a thickness of 1400 to 1700 GHz or 2300 to 2800 Å. . The method of claim 3, The light emitting layer of the pixel emitting yellow color among the second pixels is the same material as the material of the light emitting layer of the pixel emitting green color among the first pixels, and the organic light emitting display has a thickness of 1100 to 1400 mV or 1800 to 2300 mV. Device. The method of claim 3, The light emitting layer of the pixel emitting cyan among the second pixels is the same material as the material of the light emitting layer of the pixel emitting blue among the first pixels, and has an thickness of 800 to 1000 mW or 1400 to 1700 mW. Device. The method of claim 3, The light emitting layer of the pixel emitting the purple color of the second pixel is the same material as the material of the light emitting layer of the pixel emitting blue of the first pixel, the organic light emitting display device, characterized in that the thickness of 1000 to 1400Å. The method of claim 3, And a light emitting layer of the pixel emitting magenta color among the second pixels is formed by co-depositing a light emitting member of a pixel emitting red color in the light emitting layer structure of the pixel emitting blue color among the first pixels.

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