Provided is an organic light emitting element having stable performance in the air. The organic light emitting element includes: an anode; a cathode; and a first organic compound layer placed between the anode and the cathode, in which: the organic light emitting element further includes a first organic compound layer placed between the cathode and the emission layer, and a second organic compound layer placed between the emission layer and the first organic compound layer, and brought into contact with the first organic compound layer; the first organic compound layer contains a first organic compound; the second organic compound layer contains a second organic compound; and the first organic compound includes an organic compound represented by the following general formula [1], and the second organic compound includes an organic compound different from the first organic compound ##STR00001##

A method for identifying a short in a first light emitting diode element may include providing a first actuating circuit being a switched-off condition, wherein an output thereof is coupled to a first electrode of the first light emitting diode element, providing a second actuating circuit being a switched-off condition, wherein an output thereof is coupled to a first electrode of a second light emitting diode element and wherein inputs of the first and second actuating circuits, second electrodes of the first and second light emitting diode elements are electrically coupled to a first node, coupling the first electrode of the first light emitting diode element to a first connection of a test energy source, operating the first light emitting diode element in the off-state region using the test energy source, performing a check whether an electric current flows via the first light emitting diode element, and identifying the short.

An optoelectronic circuit includes at least one first and second light emitting diodes; a switch arrangement connected between the first and second diodes and configured to switch over the first and second diodes between series and parallel circuits depending on a predefined ambient parameter; and a current matching circuit for matching the currents through the first and second diodes in case of parallel connection. The current matching circuit includes a current mirror circuit, including first and second current mirror transistors connected via its collector terminal to the first/second diodes, respectively. The arrangement includes a diode/a switch for connecting the first diode in series with the second diode and is configured to form the series circuit including the first and second diodes whilst bypassing the current matching circuit so that, in case of series connection, the first transistor is switched in a high-resistance fashion and the second transistor is short-circuited.

A driving system and a driving method for a planar organic electroluminescent device are provided. The light emitting device has multiple light emitting elements, each having a first electrode and a second electrode. The driving system includes a first circuit, a second circuit, a driving module, and a ground circuit. The first circuit is connected to and provides a constant voltage to the first electrode of each light emitting element. The second circuit is connected to the second electrode of each light emitting element. The driving module is respectively connected to the second electrode of each light emitting element through the second circuit. The ground circuit is connected to the driving module and connects each light emitting element to the ground. The first electrodes of the light emitting elements are connected to one another, and the light emitting elements are driven by a constant current output by the driving module.

An apparatus and method provides a driver circuit that provides for power factor correction (PFC) to a load, such as a solid-state lighting (SSL) device, such as, for example, a light emitting diode (LED) or an array or cluster of LEDs. A programmable reference is provided in the circuit to operate in a fixed frequency peak current mode control (FFPCMC) or in a fixed frequency average current mode control (FFACMC). A driver circuit is employed to operate the SSL device using power derived from a main power source which may be DC or AC. In a FFPCMC embodiment, a programmable power reference is programmed to be a fixed DC voltage. In a FFACMC embodiment, source input current to the circuit can be programmed to be proportional to the rectified AC voltage after a bridge rectifier.

A display device includes a substrate, one line on the substrate, the one line extending from a peripheral region through a display region, pixels on the display region, the pixels being connected to the one line, an outer line on the peripheral region, the outer line being connected to the one line during a short circuit test process that detects a position of a short circuit defect, an electrostatic protection resistor on the peripheral region, the electrostatic protection resistor being connected to the outer line, a pad on the peripheral region, the pad being connected to the outer line through the electrostatic protection resistor, a short circuit test signal being applied to the pad during the short circuit test process, and a bypass line connecting a node between the pad and the electrostatic protection resistor to the outer line.

A novel organic compound having high stability is provided. The organic compound is represented by Formula (1) described in claim 1: In Formula (1), R.sub.1 and R.sub.2 each independently selected from a hydrogen atom, Substituent group A, and Substituent group B shown in claim 1, wherein at least one of R.sub.1 and R.sub.2 is selected from Substituent group A or Substituent group B; and R.sub.11 and R.sub.12 of a substituent belonging to Substituent group A are each independently selected from Substituent group B.

The present application provides a display panel having a plurality of subpixels. The display panel includes an array substrate including an array of a plurality of first thin film transistors respectively in the plurality of subpixels for driving light emission of the display panel; a counter substrate facing the array substrate and having a plurality of subpixel areas respectively in the plurality of subpixels; and an optical compensation device for adjusting in real time actual light emitting brightness values of the plurality of subpixel areas to target brightness values. The optical compensation device includes a plurality of actual light emitting brightness value detectors integrated in the counter substrate and respectively in the plurality of subpixel areas.

An OLED driving device includes an overdrive controller (ODC) which executes an overdrive of applying to an OLED an electric current larger than a rated electric current for the OLED for a predetermined period (period for the overdrive) to cause the OLED to emit brighter light for the predetermined period than at the rated electric current for the OLED for light emitting. The controller (ODC) executes a PWM control to the electric current flowing to the OLED for the predetermined period, and sets a PWM signal in the predetermined period so that at least one pulse of a pulse before the OLED starts the light emitting and a pulse at a just time when the OLED starts the light emitting has a width larger than a width of a pulse after the OLED starts the light emitting.

A stable 2,2′-bibenzo[d]imidazolidene compound is provided. The 2,2′-bibenzo[d]imidazolidene compound is expressed by the following General Formula (1). In General Formula (1), Ar.sub.1 to Ar.sub.8 each represent a substituted or unsubstituted condensed ring. R.sub.1 to R.sub.8 each represent a hydrogen atom or a substituent.

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