Provided are a photoelectric conversion device giving high photoelectric conversion efficiency and a production method thereof. A photoelectric conversion device having an anode, a cathode, an active layer containing a perovskite compound disposed between the anode and the cathode, and a hole injection layer disposed between the anode and the active layer, wherein hole injection layer is a layer having a residual film rate of 80% or more in measurement of the residual film rate after a water rinse treatment, and the material of the hole injection layer is at least one material selected from the group consisting of polythiophene and derivatives thereof, aromatic amine compounds, and polymer compounds having an aromatic amine residue containing a phenyl group having at least three substituents as a repeating unit.

A display comprises a plurality of autonomous pixels on a substrate. Each autonomous pixel comprises a display element, a sensing element and a control element. The sensing element is arranged to detect an external stimulus and the control element is arranged to generate, entirely within the autonomous pixel, a control signal to drive the display element based, at least in part, on a magnitude of the external stimulus detected by the sensing element. Additionally, the control element comprises one or more groups of transistors, each group comprising two or more transistors arranged to perform the same function and connected in parallel with each other.

A method of repairing a light emitting device assembly includes providing a light emitting device assembly including a backplane and light emitting devices, where a predominant subset of pixels in the light emitting device assembly includes an empty site for accommodating a repair light emitting device, generating a test map that identifies non-functional light emitting devices in the light emitting device assembly, providing an assembly of a repair head and repair light emitting devices, wherein the repair light emitting devices are located only on locations that are mirror images of empty sites within defective pixels that include non-functional light emitting devices, and transferring the repair light emitting devices from the repair head to the backplane in the empty site in the defective pixels.

A display device includes a pixel array including touch blocks; a plurality of test pads in a bezel area outside the pixel array for performing a pixel test and a touch block test; a plurality of pixel test lines and a plurality of touch block test lines connected to the test pads within the pixel array; a switching unit between the test pads and the pixel test lines and the touch block test lines and applying a test signal to any one of the pixel test lines and the touch block test lines; a pixel test switching pad in the bezel area and providing a control signal for testing pixel operation in the pixel array to the switching unit; and a touch block test switching pad in the bezel area and providing a control signal for testing the touch blocks within the pixel array to the switching unit.

A display device includes a display area and a non-display area adjacent to the display area; a first scan line that extends in a row direction and transmits a first scan signal; a first pixel part electrically connected to the first scan line; a second pixel part electrically connected to the first scan line and spaced apart from the first pixel part in the row direction; and a first inspection pad disposed between the first pixel part and the second pixel part and electrically connected to the first scan line.

A method for driving an organic electroluminescent element including a first light-emitting layer and a second light-emitting layer comprises: applying a second current peak value to the second light-emitting layer exhibits a lower luminous efficiency than the first light-emitting layer at a current density of the second current peak value; and applying a first current peak value to the first light-emitting layer, wherein the first current peak value has a higher current density than the second current peak value.

An embodiment of the present invention provides a display device including: a substrate including a display area in which an image is displayed and a non-display area disposed outside the display area; a pad portion disposed in the non-display area on the substrate and including a plurality of pads spaced apart by a predetermined distance; and a flexible printed circuit board bonded to the pad portion, wherein the flexible printed circuit board may include a plurality of leads, each of the plurality of pads may be bonded to each of the plurality of leads, each of the plurality of pads may include a contact pad electrode that contacts each of the plurality of leads, and the contact pad electrode may include a dummy electrode surrounding an edge of a lower surface of each of the plurality of leads.

Provided are a display substrate, a testing method therefor and a preparation method therefor, and a display panel, which are used for improving the success rate of transistor testing. The display substrate comprises a base substrate and a pixel circuit, wherein the pixel circuit comprises an active layer, a first gate insulating layer, a first gate electrode layer, a second gate insulating layer, a second gate electrode layer, a first interlayer insulating layer, a source/drain electrode layer, and a second interlayer insulating layer. The pixel circuit is divided into a plurality of transistors, and further comprises a gate electrode contact hole and a source/drain electrode contact hole. The source/drain electrode layer comprises a gate electrode test pad which is electrically connected to the first gate electrode layer by means of the gate electrode contact hole, and a source electrode and a drain electrode which are electrically connected to the active layer by means of the source/drain electrode contact hole. The second interlayer insulating layer is provided with a gate electrode test hole and a source/drain electrode test hole, wherein the gate electrode test hole exposes the gate electrode test pad, and the source/drain electrode test hole exposes part of an area in the source/drain electrode layer other than the gate electrode test pad.

Provided are a display substrate, a testing method therefor and a preparation method therefor, and a display panel, which are used for improving the success rate of transistor testing. The display substrate comprises a base substrate and a pixel circuit, wherein the pixel circuit comprises an active layer, a first gate insulating layer, a first gate electrode layer, a second gate insulating layer, a second gate electrode layer, a first interlayer insulating layer, a source/drain electrode layer, and a second interlayer insulating layer. The pixel circuit is divided into a plurality of transistors, and further comprises a gate electrode contact hole and a source/drain electrode contact hole. The source/drain electrode layer comprises a gate electrode test pad which is electrically connected to the first gate electrode layer by means of the gate electrode contact hole, and a source electrode and a drain electrode which are electrically connected to the active layer by means of the source/drain electrode contact hole. The second interlayer insulating layer is provided with a gate electrode test hole and a source/drain electrode test hole, wherein the gate electrode test hole exposes the gate electrode test pad, and the source/drain electrode test hole exposes part of an area in the source/drain electrode layer other than the gate electrode test pad.

A display apparatus including: a display region provided with a plurality of pixel portions; wires installed to the respective pixel portions within the display region from an outside of the display region for transmitting a signal to drive the respective pixel portions; connection pads provided on the outside of the display region and serving as input portions to provide the wires with a signal while electrically conducting with the wires; switch elements provided on the outside of the display region in a middle of the wires; and a light shielding covering portion shielding the switch elements from light and formed to cover the connection pads while electrically conducting with the connection pads.