OLED display

Abstract

The utility model discloses an OLED (Organic Light Emitting Diode) display, which comprises an array substrate, a group of pixel units are arranged on the array substrate, each pixel unit comprises an anode, an organic layer, a cathode layer and a packaging layer which are sequentially arranged, and the OLED display further comprises a semi-transparent reflection layer and a microcavity definition layer, the microcavity definition layer is arranged between the packaging layer and the semi-transparent reflection layer to form an external microcavity structure. The micro-cavity is realized by using the outer film layer of the device, so that the problem of process reliability caused by ITO etching is avoided; the thicknesses of the films from the cathodes to the anodes in different pixel devices are the same, so that the process problem caused by different thicknesses of the anodes ITO is avoided; the length of the RGB microcavity is adjusted by adopting the film layer outside the device, the regulation and control of the RGB peak are realized, the light emitting spectrum of the OLED is narrowed, and the high-brightness and high-color gamut display is realized.

Description

TECHNICAL FIELD

[0001] The utility model relates to OLED display technical field especially is related to a kind of OLED display. BACKGROUND

[0002] Compared with traditional AMOLED display technology, silicon-based OLED micro display uses monocrystalline silicon chip as substrate and makes its pixel size smaller and integration higher by means of mature CMOS process, which can be made into near-eye display product comparable to large-screen display and receives widespread attention.Based on its technical advantages and broad market, silicon-based OLED micro display will bring a new wave of near-eye display in military and consumer electronics field, and bring users unprecedented visual experience.

[0003] Limited by the manufacturing technology of metal mask, most of the existing high-ppi silicon-based OLED full-color products adopt WOLED (white OLED) + CF (color filter) technology. In order to realize color display, the spectrum of WOLED usually contains RGB 3 peaks. Since the light of RGB three colors corresponds to optical microcavity of different thickness, the WOLED of the current top emission structure with single optical thickness is prone to color drift, and the main reason is that under the same length of microcavity, the resonance enhancement degree of RGB three color wavelengths is different, which leads to color drift and large difference between CIE and standard (0.33, 0.33).

[0004] One of the current methods for silicon-based OLED to solve the color shift of WOLED due to different optical microcavity lengths of RGB is to make ITO film layers of different thicknesses on the anode, that is, the ITO thicknesses corresponding to RGB pixel areas are different, and the microcavity adjustment of RGB three colors in WOLED is realized through ITO thickness, but this method is complex and requires multiple coating and exposure processes, and the thickness matching between the device and ITO needs to be accurate, and there is a problem of ITO height difference, which will cause the cathode to break in the subsequent process.

[0005] As disclosed in patent CN107204400A, a display substrate, a manufacturing method thereof and a display device, comprising a substrate, an anode structure disposed on the substrate, an organic light-emitting layer disposed on the side of the anode structure away from the substrate, and a cathode layer disposed on the side of the organic light-emitting layer away from the substrate; the anode structure comprises a reflective layer and an inorganic layer disposed on the side of the reflective layer away from the substrate, and the cathode layer comprises a semi-transparent semi-reflective layer; the inorganic layer can adjust the distance between the reflective layer and the semi-transparent semi-reflective layer; thus, the reflective layer and the semi-transparent semi-reflective layer can form a microcavity effect structure. UTILITY MODEL CONTENT

[0006] The utility model provides a kind of OLED display, which utilizes the outer film layer of the device to realize microcavity, avoiding the process reliability problem caused by ITO etching.

[0007] To solve the above technical problems, the utility model adopts the technical scheme of:

[0008] The OLED display includes an array substrate, a set of pixel units are arranged on the array substrate, the pixel units include anode, organic layer, cathode layer and encapsulation layer arranged in sequence, and further include a semi-transparent reflective layer and a microcavity definition layer. The microcavity definition layer is arranged between the encapsulation layer and the semi-transparent reflective layer to form an external microcavity structure.

[0009] Further or preferably:

[0010] The semi-transparent reflective layer is provided with a protective layer and a color gel layer on the outside.

[0011] The anode thickness of different pixel units is the same.

[0012] The thickness of the microcavity definition layer corresponding to different pixel units is different.

[0013] The organic layer thickness of different pixel units is the same.

[0014] In the pixel unit, the thickness of the microcavity definition layer corresponding to sub-pixels R, G and B decreases in turn.

[0015] The cathode layer thickness of different pixel units is the same.

[0016] Compared with the prior art, the utility model has the following advantages:

[0017] The OLED display is rationally designed, utilizes the outer film layer of the device to realize microcavity, avoids the process reliability problem caused by ITO etching, and the film thickness from the cathode to the anode in different pixel devices is the same, avoiding the process problem caused by different anode ITO thickness. The utility model adjusts the RGB microcavity length by the film layer outside the device, realizes the regulation of RGB peak, narrows the OLED light spectrum, and realizes high-brightness and high-color gamut display. BRIEF DESCRIPTION OF DRAWINGS

[0018] The content expressed by each figure in the specification and the marks in the figures are briefly described as follows:

[0019] Figure 1 It is a schematic diagram of the OLED display layer structure of the utility model. DETAILED DESCRIPTION

[0020] The specific implementation manner of the utility model is further described in detail by comparing the figures and describing the embodiments.

[0021] As Figure 1 shown, the OLED display includes an array substrate, a set of pixel units are disposed on the array substrate; the pixel unit includes an anode, an organic layer, a cathode layer and an encapsulation layer disposed in sequence; further, the encapsulation layer is sequentially provided with a microcavity definition layer, a semi-transmissive reflective layer, a protective layer and a color gel layer.

[0022] The microcavity definition layer is located outside the encapsulation layer, that is, the microcavity definition layer is arranged between the encapsulation layer and the semi-transmissive reflective layer to form an external microcavity structure; which is different from the traditional internal microcavity structure; the microcavity is realized by using the outer film layer of the device, avoiding the process reliability problem caused by ITO etching.

[0023] Further, the thickness of the anode corresponding to different pixel units is the same, the thickness of the organic layer corresponding to different pixel units is the same, and the thickness of the cathode layer corresponding to different pixel units is the same. The film thickness from the cathode to the anode in different pixel devices is the same, avoiding the process problem caused by different thickness of the anode ITO.

[0024] The thickness of the microcavity definition layer corresponding to different pixel units is different; in the pixel unit, the thickness of the microcavity definition layer corresponding to the sub-pixels R, G and B decreases in turn; and the microcavity length can be adjusted, the RGB microcavity length is adjusted by using the film layer outside the device, realizing the regulation of RGB peak, narrowing the OLED light spectrum, and realizing high-brightness and high-color gamut display.

[0025] The microcavity definition layer (microcavity regulation layer) of the OLED display is set as follows:

[0026] Two thickness ITO anode structures, white light (RGB) tandem structure and three CFs are selected; wherein the characteristics and energy level matching of each material evaporation meet the requirements of OLED;

[0027] According to the OLED microcavity calculation formula: n i is the refractive index of the OLED organic layer, di is the thickness of the organic layer, is the reflection phase shift of light on the semi-transmissive and semi-reflective layer and the anode surface, λ is the microcavity resonance enhancement wavelength, m is the order of the emission mode, also known as the order of the microcavity;

[0028] In this case, the refractive index n of the organic layer is 1.75, the thickness is 200 nm, the thickness of the cathode material is 100 nm, the refractive index is 2.0, the thickness of the encapsulation layer is 500 nm, the refractive index is 1.85; the refractive index of the microcavity regulation layer is 1.7; the reflection phase shift is ignored; the wavelength of R is 618 nm, the wavelength of G is 530 nm, and the wavelength of B is 460 nm; at this time, m is 5, 6, 7, …, N; the device thickness of the OLED corresponding to RGB is shown in Table 1.

[0029] m 5 6 7 8 9 10 Microcavity control layer R 41 223 405 586 768 950 Microcavity control layer G 68 224 379 535 691 Microcavity control layer B 79 215 350 485

[0030] The R microcavity control layer corresponds to the light emitting area to obtain R peak, and the R-CF microcavity control layer corresponds to the area to obtain R light through the yellow light process; the G microcavity control layer corresponds to the light emitting area to obtain G peak, and the G-CF microcavity control layer corresponds to the area to obtain G light through the yellow light process; and the B microcavity control layer corresponds to the light emitting area to obtain B peak, and the B-CF microcavity control layer corresponds to the area to obtain B light through the yellow light process.

[0031] The present scheme adjusts the microcavity of the white light device structure, uses the film layer outside the device to control the RGB microcavity, and realizes different RGB cavity lengths; and the film layer above the cathode (microcavity control layer + semi-transparent and semi-reflective layer) outside the device is mainly used to realize the microcavity control.

[0032] The above is only the preferred embodiment of the present application, and the above technical features can be combined to form multiple embodiment schemes of the present application.

[0033] The present application is exemplarily described above in combination with the drawings, and it is obvious that the specific implementation of the present application is not limited by the above manner, as long as various non-essential improvements are made by using the concept and technical scheme of the present application, or the concept and technical scheme of the present application is directly applied to other occasions without improvement, which are all within the protection scope of the present application.

Claims

1. An OLED display, comprising an array substrate, a set of pixel units are arranged on the array substrate, the pixel units comprise an anode, an organic layer, a cathode layer and an encapsulation layer arranged in sequence, characterized in that: The semi-transmissive reflective layer is provided with a protective layer and a color glue layer outside.

2. The OLED display of claim 1, wherein: The anode thicknesses corresponding to different pixel units are the same.

3. The OLED display as described in claim 1, characterized in that: The micro-cavity definition layer thicknesses corresponding to different pixel units are different.

4. The OLED display as described in claim 1, characterized in that: The organic layer thicknesses corresponding to different pixel units are the same.

5. The OLED display as described in claim 3, characterized in that: The micro-cavity definition layer thicknesses corresponding to sub-pixels R, G and B in the pixel unit are sequentially reduced.

6. The OLED display of claim 4, wherein: The cathode layer thicknesses corresponding to different pixel units are the same.

7. The OLED display of claim 5, wherein: ​

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