Provided are boron-containing polycyclic compounds of Chemical Formula 1: ##STR00001## wherein X1 to X4 are identical to or different from one another and are each independently O, S, NR2 or CR3R4, and a to d are each 0 or 1, with the proviso that 1≤a+b+c+d, and the other substituents are as described in the specification. The compounds have a high electron accepting ability and excellent heat resistance, and can be highly purified by sublimation purification due to their high sublimation temperature. The compounds can form a stable interface with an electrode or an adjacent organic material layer of an organic light emitting device. Also provided is an organic light emitting device including the compound of Chemical Formula 1. The compound can lower driving voltage and lengthen lifetime of the organic light emitting device.

The present invention addresses the problem of providing: a luminescent thin film, a luminescent multilayered film, and an organic electroluminescent element that have luminescence properties with excellent storage stability in atmospheric air; and a production method therefor. This luminescent thin film contains a luminescent compound A, and is characterized by containing 0.0001 mass % or more of an oxide B of luminescent compound A in terms of the luminescent compound A.

Disclosed are a flexible display panel, a flexible display device and a deformation detection method thereof, used for detecting deformation of the flexible display panel. The flexible display panel provided by embodiments of the present disclosure includes a flexible substrate, a display device and a piezoelectric sensor arranged in a stacked mode. The piezoelectric sensor includes a first electrode, a second electrode, and a piezoelectric layer positioned between the first electrode and the second electrode; the piezoelectric sensor is configured to generate an electrical signal under the action of stress produced by bending the flexible display panel; and a signal processing chip in the flexible display device is configured to determine deformation parameters of the flexible display panel according to the electrical signal.

The present invention provides an electrochromic polyamic acid material, a preparation method thereof and a display device, wherein the molecular structure of the electrochromic polyamic acid material includes oligoaniline and carbazolyl triphenylamine. The oligoaniline serves as an electrochemically sensitive group, and the carbazolyl triphenylamine serves as a fluorescence emitting group. The electrochromic polyamic acid material is an electrically controlled fluorescent polymer. Fluorescence intensity of the electrochromic polyamic acid material undergoes reversible fluorescence conversion with a change of an applied voltage, due to a redox reaction of the oligoaniline at different voltages, resulting in an interchange between a benzene ring and an anthracene ring in a molecular structure, and an electron/energy transfer path with the fluorescence emitting group are generated or eliminated, thereby realizing the electrically controlled fluorescent properties of the electrochromic polyamic acid material.

The present disclosure relates to a multi-layer film. The multi-layer film may include a first region and a second region. The first region may include a first bonding layer and a first planarization layer directly contacted with each other. The second region includes a second bonding layer, a second planarization layer, and an intervention layer between the second bonding layer and the second planarization layer.

According to one embodiment, a display device includes an insulating substrate and lines. The lines include first lines each including a first linear portion and a second linear portion. The first linear portions extend in a first direction and are arranged at intervals in a second direction. The second linear portions extend in a third direction and are arranged at intervals in a fourth direction. A length of each of the first linear portions changes gradually in the second direction. A length of each of the second linear portions changes gradually in the fourth direction.

A display panel, a manufacturing method of the display panel, and a display device including the display panel are provided. The display panel includes an insulating substrate; a first circuit at a first side of the insulating substrate; and a second circuit at a second side of the insulating substrate. The first side and the second side of the insulating substrate are opposite to each other in a first direction perpendicular to a display surface, and the first circuit and the second circuit on opposing sides of the insulating substrate are electrically connected by tapered through hole and tapered pad.

A display panel includes a base, a plurality of first pixels disposed on the base, and at least one second pixel disposed on the base. The base has a plurality of island regions spaced apart and a plurality of bridge regions connecting the plurality of island regions. Each bridge region includes a first region and two second regions disposed on two opposite sides of the first region. Each second region is directly connected to a corresponding one of the plurality of island regions. The base includes a plurality of openings, each opening is disposed between two adjacent bridge regions. Each island region is provided with at least one first pixel therein. The at least one second pixel is disposed in at least one of second regions of the plurality of bridge regions.

Provided is a display substrate, a preparation method thereof and a display apparatus. The display substrate includes a base substrate, which has a display area and an encapsulation area, the encapsulation area surrounds the display area, and a hydrophobic structure is arranged on the encapsulation area.

Embodiments of the present disclosure propose a display substrate, a method for manufacturing the same, and a display panel. In an embodiment, the display substrate includes a flexible substrate, the flexible substrate includes a bending region, the bending region has a first groove, wherein at least an inner wall of the first groove has a first flexible layer, at least one rib is provided on the first flexible layer at a bottom of the first groove, a wiring layer covers the rib on the first flexible layer, and the wiring layer has alternating protrusions and recessions, and an orthographic projection of the protrusions on the flexible substrate and an orthographic projection of the rib on the flexible substrate at least partially overlap.