CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is the U.S. national phase of PCT Application No. PCT/CN2020/085088 filed on Apr. 16, 2020, which claims a priority of the Chinese patent application No. 201910553970.7 filed on Jun. 25, 2019, which are incorporated herein by reference in their entirety.

TECHNICAL FIELD

The present disclosure relates to the field of display technology, in particular to a display panel, a method of manufacturing the display panel, a method of driving the display panel and a display device.

BACKGROUND

A Micro Light-Emitting Diode (Micro-LED) display panel has been widely used in a consumer terminal (such as a mobile phone, a tablet computer) due to such characteristics as a low driving voltage and a long service life.

SUMMARY

In one aspect, a display panel is provided in some embodiments of the present disclosure, including an array substrate and a plurality of micro light-emitting diodes arranged on the array substrate, and further including: a plurality of photoelectric conversion structures in a one-to-one correspondence with the plurality of micro light-emitting diodes. The photoelectric conversion structure is located on a side of the corresponding micro light-emitting diode facing the array substrate, connected to the corresponding micro light-emitting diode, and configured to convert a received light signal emitted by the corresponding micro light-emitting diode into an electrical signal, and charge the corresponding micro light-emitting diode by using the electrical signal.

In a possible embodiment of the present disclosure, the photoelectric conversion structure includes: a photoelectric conversion diode, a control transistor and a storage capacitor. A first anode of the photoelectric conversion diode is connected to a second anode of the corresponding micro light-emitting diode, and a first cathode of the photoelectric conversion diode is connected to a second cathode of the corresponding micro light-emitting diode. A gate electrode of the control transistor is connected to a light emission control signal input terminal, a first electrode of the control transistor is connected to the second anode of the corresponding micro light-emitting diode, and a second electrode of the control transistor is connected to a first terminal of the storage capacitor. And a second terminal of the storage capacitor is connected to the second cathode of the corresponding micro light-emitting diode.

In a possible embodiment of the present disclosure, the array substrate includes a plurality of pixel driving circuits in a one-to-one correspondence with the plurality of micro light-emitting diodes, each pixel driving circuit includes a driving transistor, and an output electrode of the driving transistor is connected to the second anode of the corresponding micro light-emitting diode. The photoelectric conversion diode includes the first anode, a PIN junction and the first cathode that are sequentially stacked, and the first anode is located between the corresponding micro light-emitting diode and the first cathode.

In a possible embodiment of the present disclosure, the first anode includes a transparent electrode, and the first cathode and the output electrode of the driving transistor are arranged at a same layer and made of a same material.

In a possible embodiment of the present disclosure, the driving transistor further includes a first gate electrode and a second gate electrode that form the storage capacitor.

In a possible embodiment of the present disclosure, the display panel further includes: a planarization layer located between the array substrate and the plurality of micro light-emitting diodes and including a first via hole, a second via hole and a third via hole that are separate from each other, a pixel electrode located on a side of the planarization layer away from the array substrate and connected to the output electrode of the corresponding driving transistor through the first via hole, and a connection electrode located on the side of the planarization layer away from the array substrate and connected to the first cathode through the second via hole. The PIN junction is located in the third via hole and connected to the first cathode through the third via hole, the second anode of the micro light-emitting diode is connected to the corresponding pixel electrode, and the second cathode of the micro light-emitting diode is connected to the corresponding connection electrode.

In a possible embodiment of the present disclosure, the first anode, the pixel electrode and the connection electrode are arranged at a same layer and made of a same material.

In a possible embodiment of the present disclosure, the display panel further includes: a plurality of lens structures in a one-to-one correspondence with the plurality of micro light-emitting diodes. The lens structure is located between the corresponding micro light-emitting diode and the corresponding photoelectric conversion structure, and configured to converge the light emitted by the corresponding micro light-emitting diode and transmit the light to the corresponding photoelectric conversion structure.

In a possible embodiment of the present disclosure, the lens structure includes: a groove part and a filling part filled in the groove part. An opening of the groove part faces the micro light-emitting diode, and an inner wall of the groove part is of an arc-shape. A surface of the filling part away from the groove part and a surface surrounding the opening in the groove part together form a flat surface, and a refractive index of the filling part is larger than a refractive index of the groove part.

In a possible embodiment of the present disclosure, an orthographic projection of a PN junction of the micro light-emitting diode on a substrate of the array substrate is within an orthographic projection of the filling part on the substrate.

In a possible embodiment of the present disclosure, the PN junction of the micro light-emitting diode is located on a focal plane of the corresponding lens structure.

In a possible embodiment of the present disclosure, the PN junction of the micro light-emitting diode is located on the flat surface.

In a possible embodiment of the present disclosure, a maximum width D of the filling part in a direction parallel to the array substrate, a maximum depth H of the filling part in a direction perpendicular to the array substrate, and a focal length f are calculated by using the following formulas:

f=n1⁢rn2-n3(1)D24+(r-H)2=r2(2)n2-n3=n1⁢rf≥n1⁢D2⁢f(3)

where, r represents a curvature radius of the filling part, n1 represents a refractive index of the PN junction of the micro light-emitting diode, n2 represents the refractive index of the filling part, and n3 represents the refractive index of the groove part.

In another aspect, a display panel is further provided in some embodiments of the present disclosure, including an array substrate and a plurality of micro light-emitting diodes arranged on the array substrate, and further including: a plurality of photoelectric conversion structures in a one-to-one correspondence with the plurality of micro light-emitting diodes. The photoelectric conversion structure is located on a side of the corresponding micro light-emitting diode facing the array substrate, and the photoelectric conversion structure is connected to the corresponding micro light-emitting diode, and configured to convert a received light signal emitted by the micro light-emitting diode into an electrical signal, and charge the corresponding micro light-emitting diode by using the electrical signal. The array substrate includes a plurality of pixel driving circuits in a one-to-one correspondence with the plurality of micro light-emitting diode, each pixel driving circuit includes the photoelectric conversion structure including a photoelectric conversion diode, a ninth transistor and a storage capacitor, a first anode of the photoelectric conversion diode is connected to a second anode of the corresponding micro light-emitting diode, a first cathode of the photoelectric conversion diode is connected to a second cathode of the corresponding micro light-emitting diode, a gate electrode of the ninth transistor is connected to a light emission control signal input terminal, a first electrode of the ninth transistor is connected to the second anode of the corresponding micro light-emitting diode, a second electrode of the ninth transistor is connected to a first terminal of the storage capacitor, and a second terminal of the storage capacitor is connected to the second cathode of the corresponding micro light-emitting diode. Each pixel driving circuit further includes a first transistor, a second transistor, a third transistor, a fourth transistor, a fifth transistor, a sixth transistor, a seventh transistor, an eighth transistor, a first capacitor and a third capacitor. A gate electrode of the first transistor is connected to a reset control terminal, a first electrode of the first transistor is connected to a reset signal input terminal, and a second electrode of the first transistor is connected to a second electrode of the second transistor. A gate electrode of the second transistor is connected to a first gate control signal input terminal, a first electrode of the second transistor is connected to a second electrode of the fourth transistor, and a gate electrode of the fourth transistor is connected to the second electrode of the second transistor. A first terminal of the first capacitor is connected to a second electrode of the fifth transistor, and a second terminal of the first capacitor is connected to the second electrode of the second transistor. A gate electrode of the fifth transistor is connected to the light emission control signal input terminal, and a first electrode of the fifth transistor is connected to a first electrode of the fourth transistor. A gate electrode of the third transistor is connected to the first gate electrode control signal input terminal, a first electrode of the third transistor is connected to a first data signal input terminal, and a second electrode of the third transistor is connected to the first electrode of the fourth transistor. A gate electrode of the sixth transistor is connected to the light emission control signal input terminal, a first electrode of the sixth transistor is connected to the second electrode of the fourth transistor, and a second electrode of the sixth transistor is connected to a first electrode of the eighth transistor. A second electrode of the eighth transistor is connected to the second anode of the micro light-emitting diode, a gate electrode of the eighth transistor is connected to a first terminal of the third capacitor, and a second terminal of the third capacitor is connected to a second electrode of the seventh transistor. A first electrode of the seventh transistor is connected to a second data signal input terminal, a gate electrode of the seventh transistor is connected to a second gate control signal input terminal, and the second cathode of the micro light-emitting diode is connected to a ground signal line.

In another aspect, a display device including the display panel is further provided in some embodiments of the present disclosure.

In another aspect, a method of manufacturing the display panel is further provided in some embodiments of the present disclosure, including: forming the array substrate; forming the plurality of photoelectric conversion structures arranged on the array substrate; and forming the plurality of micro light-emitting diodes on the side of the plurality of photoelectric conversion structures away from the array substrate. The plurality of micro light-emitting diodes are in one-to-one correspondence with the plurality of photoelectric conversion structures, the photoelectric conversion structure is connected to the corresponding micro light-emitting diode, and configured to convert the received light signal emitted by the micro light-emitting diode into the electrical signal, and charge the corresponding micro light-emitting diode by using the electrical signal.

In another aspect, a method of driving the display panel is further provided in some embodiments of the present disclosure, including: in a brightness compensation step, converting, by the photoelectric conversion structure in the display panel, the received light signal emitted by the micro light-emitting diode into the electrical signal, and charging the corresponding micro light-emitting diode by using the electrical signal.

