A display substrate includes a base and blue light-emitting units disposed on the base. A blue light-emitting unit includes a first electrode, a first light-emitting layer and a second electrode that are sequentially disposed on the base. Of the first electrode and the second electrode, one electrode is configured to reflect light, and another electrode is configured to transmit light. The first light-emitting layer is configured to emit light having a spectrum whose full width at half maximum is less than or equal to 16 nm.

A display substrate includes a base and blue light-emitting units disposed on the base. A blue light-emitting unit includes a first electrode, a first light-emitting layer and a second electrode that are sequentially disposed on the base. Of the first electrode and the second electrode, one electrode is configured to reflect light, and another electrode is configured to transmit light. The first light-emitting layer is configured to emit light having a spectrum whose full width at half maximum is less than or equal to 16 nm.

A light emitting diode of an embodiment of the present disclosure includes a first electrode, a hole transport region on an upper portion of the first electrode and having a first refractive index, an emission layer on an upper portion of the hole transport region and having a second refractive index less than the first refractive index, an electron transport region on an upper portion of the emission layer, and a second electrode on an upper portion of the electron transport region.

A light emitting diode of an embodiment of the present disclosure includes a first electrode, a hole transport region on an upper portion of the first electrode and having a first refractive index, an emission layer on an upper portion of the hole transport region and having a second refractive index less than the first refractive index, an electron transport region on an upper portion of the emission layer, and a second electrode on an upper portion of the electron transport region.

A display panel, which includes: a substrate; a light-emitting element layer disposed on the substrate, including a plurality of light-emitting elements; an encapsulation layer disposed on one side of the light-emitting element layer away from the substrate; and a light energy adjustment layer disposed between the light-emitting element layer and the encapsulation layer, the light energy adjustment layer being capable of converting each wave train of light passing through it into a wave packet. Characteristic length of the wave packet is less than length of the wave train.

A display apparatus includes: a substrate including a substantially flat area and a curved area extending from the substantially flat area; a first pixel electrode arranged in the curved area; a first emission layer disposed on the first pixel electrode; a second pixel electrode arranged in the substantially flat area; a second emission layer disposed on the second pixel electrode; a first functional layer having a first thickness disposed between the first pixel electrode and the first emission layer; and a second functional layer having a second thickness disposed between the second pixel electrode and the second emission layer. The first thickness is greater than the second thickness.

A stretchable strain sensor may exhibit wavelength selectivity according to a thickness change of a thickness of the stretchable strain sensor, in a thickness direction extending parallel to the thickness of the stretchable strain sensor, due to elongation of the stretchable strain sensor in an elongation direction extending perpendicular to the thickness direction. The stretchable strain sensor may have an emission spectrum that changes according to strain variation of a strain on the stretchable strain sensor.

A light emitting diode of an embodiment of the present disclosure includes a first electrode, a hole transport region on an upper portion of the first electrode and having a first refractive index, an emission layer on an upper portion of the hole transport region and having a second refractive index less than the first refractive index, an electron transport region on an upper portion of the emission layer, and a second electrode on an upper portion of the electron transport region.

An organic-light-emitting-diode device and a fabricating method thereof, a displaying base plate and a displaying device, wherein the organic-light-emitting-diode device includes a substrate, and an anode layer, an organic functional layer and a cathode layer that are provided in stacking on one side of the substrate, wherein the organic functional layer includes a first functional layer, a second functional layer and a light emitting layer that are provided in stacking, and the first functional layer is provided closer to the anode layer; and a HOMO energy level of the second functional layer is deeper than both of a HOMO energy level of the first functional layer and a HOMO energy level of a host material of the light emitting layer.

An organic-light-emitting-diode device and a fabricating method thereof, a displaying base plate and a displaying device, wherein the organic-light-emitting-diode device includes a substrate, and an anode layer, an organic functional layer and a cathode layer that are provided in stacking on one side of the substrate, wherein the organic functional layer includes a first functional layer, a second functional layer and a light emitting layer that are provided in stacking, and the first functional layer is provided closer to the anode layer; and a HOMO energy level of the second functional layer is deeper than both of a HOMO energy level of the first functional layer and a HOMO energy level of a host material of the light emitting layer.