CROSS-REFERENCE TO RELATED APPLICATION APPLICATIONS

This application is the U.S. national phase of PCT Application No. PCT/CN2018/081886 filed on Apr. 4, 2018, which claims priority to Chinese Patent Application No. 201710505815.9 filed on Jun. 28, 2017, which are incorporated herein by reference in their entireties.

TECHNICAL FIELD

The present disclosure relates to the field of display technology, in particular to a display substrate and a display device.

BACKGROUND

Currently, Organic Light-Emitting Diode (OLED) component is a type of display component that has received much interest, and has many advantages such as low power consumption, high contrast, wide viewing angle and so forth. OLED component has an organic light-emitting layer that is made of an organic light-emitting material. In the case that electrons and holes are combined in the organic light-emitting layer, the organic light-emitting layer emits light, thereby achieving the display function of the OLED component.

A top-emitting OLED component includes a transparent cathode, an organic functional layer and a high reflectivity anode. The high reflectivity anodes can improve the light-emitting efficiency of the OLED component, but ambient light surrounding the display device can also be reflected by the high reflectivity anode when illuminates the OLED component. The stronger the ambient light, the stronger the light reflected by the high reflectivity anode, which results in a decrease in display contrast of the OLED component and seriously affects the user experience.

A filter film arranged on the top-emitting OLED component can absorb part of the ambient light, but cannot absorb the light which has certain wavelength corresponding to the filter film. The light which has the certain wavelength will still be reflected by the high reflectivity anode through the filter film. In the case that the ambient light is strong, the display contrast will still be degraded seriously.

In order to ensure the contrast of the screen, the transparent cathode can be replaced by a black cathode with higher absorption rate to the ambient light. However, the cathode with the higher light absorption rate absorbs the light emitted from the OLED component as well as the ambient light, thereby causing the light-emitting efficiency of the OLED component degraded seriously.

SUMMARY

The object of the present disclosure is to provide an OLED display component and a display device capable of ensuring both the light-emitting efficiency of the OLED component and the display contrast of the display device.

In one aspect, at least one embodiment of the present disclosure provides a display substrate. The display substrate includes a first electrode structure, an organic light-emitting layer and a second electrode structure sequentially arranged on a base substrate. The display substrate further includes a filter film located on a light-emitting side of the display substrate. A light absorption rate of a first electrode structure or a second electrode structure is greater than a first threshold.

Optionally, in some embodiments, in the case that the light absorption rate of the second electrode structure located on a light-emitting side of the display substrate is greater than the first threshold, in a direction from a side close to the organic light-emitting layer to a side away from the organic light-emitting layer, the second electrode structure includes a second transparent electrode film, a phase difference layer and a light absorbing layer in order. A thickness of the phase difference layer is an odd multiple of a half wavelength of visible light. The light reflectivity of the light absorbing layer is lower than a second threshold, and the light absorption rate of the light absorbing layer to light emitted by the organic light-emitting layer is less than a third threshold.

Optionally, in some embodiments, the display substrate includes green pixel regions, red pixel regions, and blue pixel regions. In the green pixel region, the display substrate further includes a reflective absorbing film located on a side of the light absorbing layer away from the organic light-emitting layer. Microcavities are formed between the reflective absorbing film and the second transparent electrode film. The light reflectivity of the reflective absorbing film is less than a fourth threshold. The light absorption rate of the reflective absorbing film to ambient light is greater than a fifth threshold.

Optionally, in some embodiments, the second electrode structure further includes a light auxiliary layer located on the light-emitting side of the display substrate. The light auxiliary layer is configured to improve light-emitting efficiency of the display substrate.

Optionally, in some embodiments, in the case that the light absorption rate of the first electrode structure located on a non-light-emitting side of the display substrate is greater than the first threshold, in a direction from a side close to the organic light-emitting layer to a side away from the organic light-emitting layer, the first electrode structure includes a first transparent electrode film, a phase difference layer and a reflective film in order. A thickness of the phase difference layer is an odd multiple of a half wavelength of visible light. The light reflectivity of the reflective film is greater than a sixth threshold.

Optionally, in some embodiments, the first electrode structure further includes a light absorbing layer located between the first transparent electrode film and the phase difference layer. The light reflectivity of the light absorbing layer is less than a second threshold, and the light absorption rate of the light absorbing layer is less than a third threshold. At the light absorbing layer, light reflected by the interface between the light absorbing layer and the phase difference layer interferes with the light passing through the phase difference layer and reflected by the reflective film.

Optionally, in some embodiments, the phase difference layer is made of Alq3, MoO3, LiF or MgF2.

Optionally, in some embodiments, the light absorbing layer is made of Alq3doped with Ag.

Optionally, in some embodiments, the reflective absorbing film is made of Al, Cr or AgMg.

Optionally, in some embodiments, the first electrode structure is an anode; the second electrode structure is a cathode, and the first threshold is 40% or 45%.

Optionally, in some embodiments, the second threshold is 30%; the third threshold is 15%.

Optionally, in some embodiments, the fourth threshold is 20%; the fifth threshold is 1.5%.

Optionally, in some embodiments, the light reflectivity of the reflective absorbing film is 2% to 20%; the light absorption rate is 1.5%-15%.

Optionally, in some embodiments, the light auxiliary layer is made of an inorganic material, such as ZnSe or Lif, or organic material.

Optionally, in some embodiments, the sixth threshold is 90%.

The embodiments of the present disclosure further disclose a display device including the display substrate as described above.

The embodiments of the present disclosure have the following beneficial effects: in the above technical solutions, an electrode structure having a high light absorption rate is combined with a filter film. The ambient light is mostly absorbed after passing through the filter film. Then the ambient light is further absorbed by the electrode structure. Since the filter film has absorbed most of the ambient light, a requirement to the light reflectivity of the display substrate to the ambient light can be met without setting a high light absorption rate of the electrode structure, thereby maintaining the light-emitting efficiency of the OLED component.

