Optical antireflection structure, bottom emission electroluminescent device and preparation method

Abstract

The invention relates to an optical antireflection structure, an electroluminescent device and a preparation method. The light extraction layer of the optical antireflection structure is prepared by aBi2O3 material which has a forbidden bandwidth of 2.8eV to 3eV, little absorption and high transmittance in a visible light region, and a high refractive index. For different preparation processes, the refractive index is generally from 1.8 to 2.2. When formed into a film, the Bi2O3 material is likely to form a rough surface where small particles protrude such that the surface of the light extraction layer has certain roughness. The particle protrusions of the rough surface can be used as a scattering unit to enhance the diffusion of light, reduce total reflection, and increase a light extraction rate. Therefore, the light extraction efficiency can be improved by inserting the Bi2O3 light extraction layer between a transparent anode layer and a transparent substrate. The Bi2O3 light extraction layer can be prepared by spin coating, magnetron sputtering or deposition, and is simple in process, low in cost is low, and good in film forming property.

Description

technical field [0001] The invention relates to the technical field of electroluminescence, in particular to an optical anti-reflection structure, a bottom emission electroluminescence device and a preparation method. Background technique [0002] OLED (Organic Light-Emitting Diode, Organic Light-Emitting Diode) and other electroluminescent devices are used in the new generation of mobile phone screens, computer monitors, Full-color TV and other fields have received widespread attention. Compared with traditional LCDs, this type of electroluminescent device does not require a backlight. When current passes through the organic functional layer, these organic materials can emit light, thereby greatly reducing the thickness and energy consumption of the display screen. [0003] However, the light extraction efficiency of traditional bottom-emitting electroluminescent devices is very low. This is because the light is directly injected into the glass substrate from the anode lay...

AI Technical Summary

Problems solved by technology

[0003] However, the light extraction efficiency of traditional bottom-emitting electroluminescent devices is very low. This is because the light is directly injected into the glass substrate from the anode layer with high refractive index, and then injected into the air from the glass substrate, and total reflection occurs at the two interfaces. And a lot of losses

It is estimated that about 60% of the light is captured by the interface of the anode layer / glass substrate, about 20% of the light is captured by the interface of the glass substrate / air, and only about 20% of the light can be transmitted, and the light extraction efficiency is very low

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