CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of priority to Chinese Patent Application No. 201910152093.2 filed on Feb. 28, 2019, the contents of which are incorporated herein in their entirety by reference.

TECHNICAL FIELD

The present disclosure relates to the field of display devices, and in particular, to a light emitting diode display panel and a method for manufacturing the light emitting diode display panel.

BACKGROUND

Light emitting diode (LED) display panels are widely used due to their advantages of self-luminescence, short response time, high definition, high contrast, etc.

However, luminous efficiency and power consumption of the LED display panel are still important factors that restrict the development of the LED display panel.

SUMMARY

As an aspect of the present disclosure, there is provided a light emitting diode display panel including: a substrate; a light emitting diode on the substrate; a pixel defining layer on the substrate and defining a pixel opening, the light emitting diode being within the pixel opening; and a first encapsulation layer on a light emitting side of the light emitting diode. A portion of the first encapsulation layer within the pixel opening includes a sidewall inclined with respect to the substrate, a surface of the sidewall close to the light emitting diode includes a plurality of first portions and a plurality of second portions alternately arranged in a direction away from the light emitting diode and connected to each other, and inclination angles of the plurality of first portions with respect to the substrate are smaller than inclination angles of the plurality of second portions with respect to the substrate. A refractive index of a material of the first encapsulation layer is greater than a refractive index of a material of each of layer structures directly on both sides of the first encapsulation layer in a direction perpendicular to the substrate.

In an embodiment of the present disclosure, the plurality of first portions are parallel to the substrate.

In an embodiment of the present disclosure, the inclination angles of the plurality of second portions with respect to the substrate increase in the direction away from the light emitting diode.

In an embodiment of the present disclosure, the pixel defining layer includes a plurality of pixel defining sub-layers stacked in a direction away from the substrate, the pixel opening includes a plurality of pixel sub-openings respectively penetrating through the plurality of pixel defining sub-layers, and opening areas of the plurality of pixel sub-openings increase in the direction away from the substrate.

In an embodiment of the present disclosure, inclination angles of sides of the plurality of pixel sub-openings with respect to the substrate increase in the direction away from the substrate.

In an embodiment of the present disclosure, a material of each pixel defining sub-layer includes a negative photoresist containing a photosensitizer, and a pixel defining sub-layer farther away from the substrate has a higher photosensitizer content.

In an embodiment of the present disclosure, the pixel defining layer includes three pixel defining sub-layers, a photosensitizer content in a pixel defining sub-layer closest to the substrate is 1.5 wt % to 2.5 wt %, a photosensitizer content in a pixel defining sub-layer farthest from the substrate is 4 wt % to 5 wt %, and a photosensitizer content in a pixel defining sub-layer in the middle of the three pixel defining sub-layers is 2.8 wt % to 3.8 wt %.

In an embodiment of the present disclosure, the first encapsulation layer is made of an inorganic material.

In an embodiment of the present disclosure, the light emitting diode display panel further includes a second encapsulation layer directly on a side of the first encapsulation layer away from the light emitting diode, the second encapsulation layer is made of an organic material, and a refractive index of the first encapsulation layer is greater than a refractive index of the second encapsulation layer.

In an embodiment of the present disclosure, the light emitting diode includes a first electrode, the first encapsulation layer is directly on the first electrode, and the first electrode is conformal with the first encapsulation layer.

In an embodiment of the present disclosure, the first electrode is a transparent electrode.

In an embodiment of the present disclosure, the first encapsulation layer is uniform in thickness.

In an embodiment of the present disclosure, the light emitting diode display panel further includes a driver circuit layer between the substrate and the pixel defining layer and configured to drive the light emitting diode to emit light.

As another aspect of the present disclosure, there is provided a method for manufacturing a light emitting diode display panel, including: providing a substrate; forming a pixel defining layer on the substrate, the pixel defining layer defining a pixel opening; forming a light emitting diode on the substrate, the light emitting diode being formed within the pixel opening; forming a first encapsulation layer on a light emitting side of the light emitting diode such that a portion of the first encapsulation layer within the pixel opening includes a sidewall inclined with respect to the substrate, a surface of the sidewall close to the light emitting diode includes a plurality of first portions and a plurality of second portions alternately arranged in a direction away from the light emitting diode and connected to each other, and inclination angles of the plurality of first portions with respect to the substrate are smaller than inclination angles of the plurality of second portions with respect to the substrate. A refractive index of a material of the first encapsulation layer is greater than a refractive index of a material of each of layer structures directly on both sides of the first encapsulation layer in a direction perpendicular to the substrate.

In an embodiment of the present disclosure, the plurality of first portions are formed to be parallel to the substrate.

In an embodiment of the present disclosure, the inclination angles of the plurality of second portions with respect to the substrate increase in the direction away from the light emitting diode.

In an embodiment of the present disclosure, forming the pixel defining layer includes: forming a plurality of pixel defining sub-layers which are stacked in a direction away from the substrate, the pixel opening includes a plurality of pixel sub-openings respectively penetrating through the plurality of pixel defining sub-layers, and opening areas of the plurality of pixel sub-openings increase in the direction away from the substrate.

In an embodiment of the present disclosure, inclination angles of sides of the plurality of pixel sub-openings with respect to the substrate increase in the direction away from the substrate.

In an embodiment of the present disclosure, forming the pixel defining layer includes: sequentially forming a plurality of pixel defining material layers, wherein a material of each pixel defining material layer includes a negative photoresist and a photosensitizer, and a pixel defining material layer farther away from the substrate has a higher photosensitizer content; exposing a stacked structure formed by the plurality of pixel defining material layers by using a same mask; developing the stacked structure to obtain the pixel opening, wherein the pixel opening includes a plurality of pixel sub-openings which sequentially penetrate through the plurality of pixel defining material layers, and among the plurality of pixel sub-openings, a pixel sub-opening which is farther away from the substrate has a greater opening area.

In an embodiment of the present disclosure, in sequentially forming the plurality of pixel defining material layers, three pixel defining material layers are formed, wherein a photosensitizer content in a pixel defining material layer closest to the substrate is 1.5 wt % to 2.5 wt %, a photosensitizer content in a pixel defining material layer farthest from the substrate is 4 wt % to 5 wt %, and a photosensitizer content in a pixel defining material layer in the middle of the three pixel defining material layers is 2.8 wt % to 3.8 wt %.

